How to resolve a wildcard filespec using Java 7 - java

I've searched, but can't seem to figure out how to write java code that takes as input a String containing a wildcard (asterisk), and outputs a String with the wildcard resolved.
I have a special situation where I know there is either 1 or 0 matching filespecs, so I'd like to have the returned String either be a valid filespec, or null.
I've gotten some example code to work using Files.walkFileTree(), but it doesn't do exactly what I want. I want to get the resollved filename back as a String that I can use in subsequent code...
I simply want to pass some code a String filename that includes an asterisk
e.g.: input this String: filename*.tr
and get back a String with the asterisk resolved to the 1st matching filename (or null):
e.g.: get back this String: filename_201402041230.tr
The directory where these files reside contains several thousand files, so iterating over all files in the directory and parsing the names myself isn't an attractive option.
Any help or pointers would be greatly appreciated.
Apologize for the outburst... Thanks for the tip... Here's what I was trying before:
However, as I said this isn't what I want, but it's as close as I could get from my RESEARCH.
Path startDir = Paths.get("C:\\huge_dir");
String pattern = "filename*.tr";
FileSystem fs = FileSystems.getDefault();
final PathMatcher matcher = fs.getPathMatcher("glob:" + pattern);
FileVisitor<Path> matcherVisitor = new SimpleFileVisitor<Path>()
{
#Override public FileVisitResult visitFile(Path file, BasicFileAttributes attribs)
{
Path name = file.getFileName();
if (matcher.matches(name))
System.out.println(file);
return FileVisitResult.TERMINATE;
}
};
try
{
Files.walkFileTree(startDir, matcherVisitor);
}
catch (Exception e){System.out.println(e);}

You can use the nio2 Files.newDirectoryStream method with an additional pattern matcher to only list files which match the pattern. As your string already is a glob pattern, you can just pass it as the second argument:
String pattern = "filename*.tr"
try (DirectoryStream<Path> ds = Files.newDirectoryStream(dir, pattern)) {
//iterate over all matching files
List<Path> paths = new ArrayList<>();
for (Path path : ds) {
paths.add(path);
}
if (paths.isEmpty()) {
//no file found
} else if (paths.size() == 1) {
//found one result
Path result = paths.get(0) //now do whatever
} else {
//more than one match - probably an error in your case?
}
}

Related

How to get sub path from the given file path

I want to get path after given token "html" which is a fix token and file path is below
String token = "html"
Path path = D:\data\test\html\css\Core.css
Expected Output : css\Core.css
below is input folder for the program. and defined as the constant in the code.
public static final String INPUT_DIR = "D:\data\test\html"
which will contains input html, css, js files. and want to copy these files to different location E:\data\test\html\ here so just need to extract sub path after html from the input file path to append it to the output path.
lets say input file are
D:\data\test\html\css\Core.css
D:\data\test\html\css\Core.html
D:\data\test\html\css\Core.js
so want to extract css\Core.css, css\Core.html, css\Core.js to append it to the destination path E:\data\test\html\ to copy it.
Tried below
String [] array = path.tostring().split("html");
String subpath = array[1];
Output : \css\Core.css
which is not expected output expected output is css\Core.css
Also above code is not working for below path
Path path = D:\data\test\html\bla\bla\html\css\Core.css;
String [] array = path.toString().split("html");
String subpath = array[1];
In this case I am getting something like \bla\bla\ which is not
expected.
If you only need the path in the form of a string another solution would be to use this code:
String path = "D:\\data\\test\\html\\css\\Core.css";
String keyword = "\\html";
System.out.println(path.substring(path.lastIndexOf(keyword) + keyword.length()).trim());
You can replace the path with file.getAbsolutePath() as mentioned above.
import java.io.File;
public class Main {
public static void main(String[] args) {
// Create a File object for the directory that you want to start from
File directory = new File("/path/to/starting/directory");
// Get a list of all files and directories in the directory
File[] files = directory.listFiles();
// Iterate through the list of files and directories
for (File file : files) {
// Check if the file is a directory
if (file.isDirectory()) {
// If it's a directory, recursively search for the file
findFile(file, "target-file.txt");
} else {
// If it's a file, check if it's the target file
if (file.getName().equals("target-file.txt")) {
// If it's the target file, print the file path
System.out.println(file.getAbsolutePath());
}
}
}
}
public static void findFile(File directory, String targetFileName) {
// Get a list of all files and directories in the directory
File[] files = directory.listFiles();
// Iterate through the list of files and directories
for (File file : files) {
// Check if the file is a directory
if (file.isDirectory()) {
// If it's a directory, recursively search for the file
findFile(file, targetFileName);
} else {
// If it's a file, check if it's the target file
if (file.getName().equals(targetFileName)) {
// If it's the target file, print the file path
System.out.println(file.getAbsolutePath());
}
}
}
}
}
This code uses a recursive function to search through all subdirectories of the starting directory and print the file path of the target file (in this case, "target-file.txt") if it is found.
You can modify this code to suit your specific needs, such as changing the starting directory or target file name. You can also modify the code to perform different actions on the target file, such as reading its contents or copying it to another location.
Your question lacks details.
Is the "path" a Path or a String?
How do you determine which part of the "path" you want?
Do you know the entire structure of the "path" or do you just have the delimiting part, for example the html?
Here are six different ways (without iterating, as you stated in your comment). The first two use methods of java.nio.file.Path. The next two use methods of java.lang.String. The last two use regular expressions. Note that there are probably also other ways.
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class PathTest {
public static void main(String[] args) {
// D:\data\test\html\css\Core.css
Path path = Paths.get("D:", "data", "test", "html", "css", "Core.css");
System.out.println("Path: " + path);
Path afterHtml = Paths.get("D:", "data", "test", "html").relativize(path);
System.out.println("After 'html': " + afterHtml);
System.out.println("subpath(3): " + path.subpath(3, path.getNameCount()));
String str = path.toString();
System.out.println("replace: " + str.replace("D:\\data\\test\\html\\", ""));
System.out.println("substring: " + str.substring(str.indexOf("html") + 5));
System.out.println("split: " + str.split("\\\\html\\\\")[1]);
Pattern pattern = Pattern.compile("\\\\html\\\\(.*$)");
Matcher matcher = pattern.matcher(str);
if (matcher.find()) {
System.out.println("regex: " + matcher.group(1));
}
}
}
Running the above code produces the following output:
Path: D:\data\test\html\css\Core.css
After 'html': css\Core.css
subpath(3): css\Core.css
replace: css\Core.css
substring: css\Core.css
split: css\Core.css
regex: css\Core.css
I assume you know how to modify the above in order to
I want to get file path after /test

Java: Is there a way, how I can import a file which is in the same folder as the .jar? [duplicate]

Want to improve this post? Provide detailed answers to this question, including citations and an explanation of why your answer is correct. Answers without enough detail may be edited or deleted.
My code runs inside a JAR file, say foo.jar, and I need to know, in the code, in which folder the running foo.jar is.
So, if foo.jar is in C:\FOO\, I want to get that path no matter what my current working directory is.
return new File(MyClass.class.getProtectionDomain().getCodeSource().getLocation()
.toURI()).getPath();
Replace "MyClass" with the name of your class.
Obviously, this will do odd things if your class was loaded from a non-file location.
Best solution for me:
String path = Test.class.getProtectionDomain().getCodeSource().getLocation().getPath();
String decodedPath = URLDecoder.decode(path, "UTF-8");
This should solve the problem with spaces and special characters.
To obtain the File for a given Class, there are two steps:
Convert the Class to a URL
Convert the URL to a File
It is important to understand both steps, and not conflate them.
Once you have the File, you can call getParentFile to get the containing folder, if that is what you need.
Step 1: Class to URL
As discussed in other answers, there are two major ways to find a URL relevant to a Class.
URL url = Bar.class.getProtectionDomain().getCodeSource().getLocation();
URL url = Bar.class.getResource(Bar.class.getSimpleName() + ".class");
Both have pros and cons.
The getProtectionDomain approach yields the base location of the class (e.g., the containing JAR file). However, it is possible that the Java runtime's security policy will throw SecurityException when calling getProtectionDomain(), so if your application needs to run in a variety of environments, it is best to test in all of them.
The getResource approach yields the full URL resource path of the class, from which you will need to perform additional string manipulation. It may be a file: path, but it could also be jar:file: or even something nastier like bundleresource://346.fwk2106232034:4/foo/Bar.class when executing within an OSGi framework. Conversely, the getProtectionDomain approach correctly yields a file: URL even from within OSGi.
Note that both getResource("") and getResource(".") failed in my tests, when the class resided within a JAR file; both invocations returned null. So I recommend the #2 invocation shown above instead, as it seems safer.
Step 2: URL to File
Either way, once you have a URL, the next step is convert to a File. This is its own challenge; see Kohsuke Kawaguchi's blog post about it for full details, but in short, you can use new File(url.toURI()) as long as the URL is completely well-formed.
Lastly, I would highly discourage using URLDecoder. Some characters of the URL, : and / in particular, are not valid URL-encoded characters. From the URLDecoder Javadoc:
It is assumed that all characters in the encoded string are one of the following: "a" through "z", "A" through "Z", "0" through "9", and "-", "_", ".", and "*". The character "%" is allowed but is interpreted as the start of a special escaped sequence.
...
There are two possible ways in which this decoder could deal with illegal strings. It could either leave illegal characters alone or it could throw an IllegalArgumentException. Which approach the decoder takes is left to the implementation.
In practice, URLDecoder generally does not throw IllegalArgumentException as threatened above. And if your file path has spaces encoded as %20, this approach may appear to work. However, if your file path has other non-alphameric characters such as + you will have problems with URLDecoder mangling your file path.
Working code
To achieve these steps, you might have methods like the following:
/**
* Gets the base location of the given class.
* <p>
* If the class is directly on the file system (e.g.,
* "/path/to/my/package/MyClass.class") then it will return the base directory
* (e.g., "file:/path/to").
* </p>
* <p>
* If the class is within a JAR file (e.g.,
* "/path/to/my-jar.jar!/my/package/MyClass.class") then it will return the
* path to the JAR (e.g., "file:/path/to/my-jar.jar").
* </p>
*
* #param c The class whose location is desired.
* #see FileUtils#urlToFile(URL) to convert the result to a {#link File}.
*/
public static URL getLocation(final Class<?> c) {
if (c == null) return null; // could not load the class
// try the easy way first
try {
final URL codeSourceLocation =
c.getProtectionDomain().getCodeSource().getLocation();
if (codeSourceLocation != null) return codeSourceLocation;
}
catch (final SecurityException e) {
// NB: Cannot access protection domain.
}
catch (final NullPointerException e) {
// NB: Protection domain or code source is null.
}
// NB: The easy way failed, so we try the hard way. We ask for the class
// itself as a resource, then strip the class's path from the URL string,
// leaving the base path.
// get the class's raw resource path
final URL classResource = c.getResource(c.getSimpleName() + ".class");
if (classResource == null) return null; // cannot find class resource
final String url = classResource.toString();
final String suffix = c.getCanonicalName().replace('.', '/') + ".class";
if (!url.endsWith(suffix)) return null; // weird URL
// strip the class's path from the URL string
final String base = url.substring(0, url.length() - suffix.length());
String path = base;
// remove the "jar:" prefix and "!/" suffix, if present
if (path.startsWith("jar:")) path = path.substring(4, path.length() - 2);
try {
return new URL(path);
}
catch (final MalformedURLException e) {
e.printStackTrace();
return null;
}
}
/**
* Converts the given {#link URL} to its corresponding {#link File}.
* <p>
* This method is similar to calling {#code new File(url.toURI())} except that
* it also handles "jar:file:" URLs, returning the path to the JAR file.
* </p>
*
* #param url The URL to convert.
* #return A file path suitable for use with e.g. {#link FileInputStream}
* #throws IllegalArgumentException if the URL does not correspond to a file.
*/
public static File urlToFile(final URL url) {
return url == null ? null : urlToFile(url.toString());
}
/**
* Converts the given URL string to its corresponding {#link File}.
*
* #param url The URL to convert.
* #return A file path suitable for use with e.g. {#link FileInputStream}
* #throws IllegalArgumentException if the URL does not correspond to a file.
*/
public static File urlToFile(final String url) {
String path = url;
if (path.startsWith("jar:")) {
// remove "jar:" prefix and "!/" suffix
final int index = path.indexOf("!/");
path = path.substring(4, index);
}
try {
if (PlatformUtils.isWindows() && path.matches("file:[A-Za-z]:.*")) {
path = "file:/" + path.substring(5);
}
return new File(new URL(path).toURI());
}
catch (final MalformedURLException e) {
// NB: URL is not completely well-formed.
}
catch (final URISyntaxException e) {
// NB: URL is not completely well-formed.
}
if (path.startsWith("file:")) {
// pass through the URL as-is, minus "file:" prefix
path = path.substring(5);
return new File(path);
}
throw new IllegalArgumentException("Invalid URL: " + url);
}
You can find these methods in the SciJava Common library:
org.scijava.util.ClassUtils
org.scijava.util.FileUtils.
You can also use:
CodeSource codeSource = YourMainClass.class.getProtectionDomain().getCodeSource();
File jarFile = new File(codeSource.getLocation().toURI().getPath());
String jarDir = jarFile.getParentFile().getPath();
Use ClassLoader.getResource() to find the URL for your current class.
For example:
package foo;
public class Test
{
public static void main(String[] args)
{
ClassLoader loader = Test.class.getClassLoader();
System.out.println(loader.getResource("foo/Test.class"));
}
}
(This example taken from a similar question.)
To find the directory, you'd then need to take apart the URL manually. See the JarClassLoader tutorial for the format of a jar URL.
I'm surprised to see that none recently proposed to use Path. Here follows a citation: "The Path class includes various methods that can be used to obtain information about the path, access elements of the path, convert the path to other forms, or extract portions of a path"
Thus, a good alternative is to get the Path objest as:
Path path = Paths.get(Test.class.getProtectionDomain().getCodeSource().getLocation().toURI());
The only solution that works for me on Linux, Mac and Windows:
public static String getJarContainingFolder(Class aclass) throws Exception {
CodeSource codeSource = aclass.getProtectionDomain().getCodeSource();
File jarFile;
if (codeSource.getLocation() != null) {
jarFile = new File(codeSource.getLocation().toURI());
}
else {
String path = aclass.getResource(aclass.getSimpleName() + ".class").getPath();
String jarFilePath = path.substring(path.indexOf(":") + 1, path.indexOf("!"));
jarFilePath = URLDecoder.decode(jarFilePath, "UTF-8");
jarFile = new File(jarFilePath);
}
return jarFile.getParentFile().getAbsolutePath();
}
If you are really looking for a simple way to get the folder in which your JAR is located you should use this implementation.
Solutions like this are hard to find and many solutions are no longer supported, many others provide the path of the file instead of the actual directory. This is easier than other solutions you are going to find and works for java version 1.12.
new File(".").getCanonicalPath()
Gathering the Input from other answers this is a simple one too:
String localPath=new File(getClass().getProtectionDomain().getCodeSource().getLocation().toURI()).getParentFile().getPath()+"\\";
Both will return a String with this format:
"C:\Users\User\Desktop\Folder\"
In a simple and concise line.
I had the the same problem and I solved it that way:
File currentJavaJarFile = new File(Main.class.getProtectionDomain().getCodeSource().getLocation().getPath());
String currentJavaJarFilePath = currentJavaJarFile.getAbsolutePath();
String currentRootDirectoryPath = currentJavaJarFilePath.replace(currentJavaJarFile.getName(), "");
I hope I was of help to you.
Here's upgrade to other comments, that seem to me incomplete for the specifics of
using a relative "folder" outside .jar file (in the jar's same
location):
String path =
YourMainClassName.class.getProtectionDomain().
getCodeSource().getLocation().getPath();
path =
URLDecoder.decode(
path,
"UTF-8");
BufferedImage img =
ImageIO.read(
new File((
new File(path).getParentFile().getPath()) +
File.separator +
"folder" +
File.separator +
"yourfile.jpg"));
For getting the path of running jar file I have studied the above solutions and tried all methods which exist some difference each other. If these code are running in Eclipse IDE they all should be able to find the path of the file including the indicated class and open or create an indicated file with the found path.
But it is tricky, when run the runnable jar file directly or through the command line, it will be failed as the path of jar file gotten from the above methods will give an internal path in the jar file, that is it always gives a path as
rsrc:project-name (maybe I should say that it is the package name of the main class file - the indicated class)
I can not convert the rsrc:... path to an external path, that is when run the jar file outside the Eclipse IDE it can not get the path of jar file.
The only possible way for getting the path of running jar file outside Eclipse IDE is
System.getProperty("java.class.path")
this code line may return the living path (including the file name) of the running jar file (note that the return path is not the working directory), as the java document and some people said that it will return the paths of all class files in the same directory, but as my tests if in the same directory include many jar files, it only return the path of running jar (about the multiple paths issue indeed it happened in the Eclipse).
Other answers seem to point to the code source which is Jar file location which is not a directory.
Use
return new File(MyClass.class.getProtectionDomain().getCodeSource().getLocation().toURI().getPath()).getParentFile();
the selected answer above is not working if you run your jar by click on it from Gnome desktop environment (not from any script or terminal).
Instead, I have fond that the following solution is working everywhere:
try {
return URLDecoder.decode(ClassLoader.getSystemClassLoader().getResource(".").getPath(), "UTF-8");
} catch (UnsupportedEncodingException e) {
return "";
}
I had to mess around a lot before I finally found a working (and short) solution.
It is possible that the jarLocation comes with a prefix like file:\ or jar:file\, which can be removed by using String#substring().
URL jarLocationUrl = MyClass.class.getProtectionDomain().getCodeSource().getLocation();
String jarLocation = new File(jarLocationUrl.toString()).getParent();
For the jar file path:
String jarPath = new File(MyClass.class.getProtectionDomain().getCodeSource().getLocation()
.toURI()).getPath();
For getting the directory path of that jar file:
String dirPath = new File(MyClass.class.getProtectionDomain().getCodeSource().getLocation()
.toURI()).getParent();
The results of the two lines above are like this:
/home/user/MyPrograms/myapp/myjar.jar (value of jarPath)
/home/user/MyPrograms/myapp (value of dirPath)
public static String dir() throws URISyntaxException
{
URI path=Main.class.getProtectionDomain().getCodeSource().getLocation().toURI();
String name= Main.class.getPackage().getName()+".jar";
String path2 = path.getRawPath();
path2=path2.substring(1);
if (path2.contains(".jar"))
{
path2=path2.replace(name, "");
}
return path2;}
Works good on Windows
I tried to get the jar running path using
String folder = MyClassName.class.getProtectionDomain().getCodeSource().getLocation().getPath();
c:\app>java -jar application.jar
Running the jar application named "application.jar", on Windows in the folder "c:\app", the value of the String variable "folder" was "\c:\app\application.jar" and I had problems testing for path's correctness
File test = new File(folder);
if(file.isDirectory() && file.canRead()) { //always false }
So I tried to define "test" as:
String fold= new File(folder).getParentFile().getPath()
File test = new File(fold);
to get path in a right format like "c:\app" instead of "\c:\app\application.jar" and I noticed that it work.
The simplest solution is to pass the path as an argument when running the jar.
You can automate this with a shell script (.bat in Windows, .sh anywhere else):
java -jar my-jar.jar .
I used . to pass the current working directory.
UPDATE
You may want to stick the jar file in a sub-directory so users don't accidentally click it. Your code should also check to make sure that the command line arguments have been supplied, and provide a good error message if the arguments are missing.
Actually here is a better version - the old one failed if a folder name had a space in it.
private String getJarFolder() {
// get name and path
String name = getClass().getName().replace('.', '/');
name = getClass().getResource("/" + name + ".class").toString();
// remove junk
name = name.substring(0, name.indexOf(".jar"));
name = name.substring(name.lastIndexOf(':')-1, name.lastIndexOf('/')+1).replace('%', ' ');
// remove escape characters
String s = "";
for (int k=0; k<name.length(); k++) {
s += name.charAt(k);
if (name.charAt(k) == ' ') k += 2;
}
// replace '/' with system separator char
return s.replace('/', File.separatorChar);
}
As for failing with applets, you wouldn't usually have access to local files anyway. I don't know much about JWS but to handle local files might it not be possible to download the app.?
String path = getClass().getResource("").getPath();
The path always refers to the resource within the jar file.
Try this:
String path = new File("").getAbsolutePath();
This code worked for me to identify if the program is being executed inside a JAR file or IDE:
private static boolean isRunningOverJar() {
try {
String pathJar = Application.class.getResource(Application.class.getSimpleName() + ".class").getFile();
if (pathJar.toLowerCase().contains(".jar")) {
return true;
} else {
return false;
}
} catch (Exception e) {
return false;
}
}
If I need to get the Windows full path of JAR file I am using this method:
private static String getPathJar() {
try {
final URI jarUriPath =
Application.class.getResource(Application.class.getSimpleName() + ".class").toURI();
String jarStringPath = jarUriPath.toString().replace("jar:", "");
String jarCleanPath = Paths.get(new URI(jarStringPath)).toString();
if (jarCleanPath.toLowerCase().contains(".jar")) {
return jarCleanPath.substring(0, jarCleanPath.lastIndexOf(".jar") + 4);
} else {
return null;
}
} catch (Exception e) {
log.error("Error getting JAR path.", e);
return null;
}
}
My complete code working with a Spring Boot application using CommandLineRunner implementation, to ensure that the application always be executed within of a console view (Double clicks by mistake in JAR file name), I am using the next code:
#SpringBootApplication
public class Application implements CommandLineRunner {
public static void main(String[] args) throws IOException {
Console console = System.console();
if (console == null && !GraphicsEnvironment.isHeadless() && isRunningOverJar()) {
Runtime.getRuntime().exec(new String[]{"cmd", "/c", "start", "cmd", "/k",
"java -jar \"" + getPathJar() + "\""});
} else {
SpringApplication.run(Application.class, args);
}
}
#Override
public void run(String... args) {
/*
Additional code here...
*/
}
private static boolean isRunningOverJar() {
try {
String pathJar = Application.class.getResource(Application.class.getSimpleName() + ".class").getFile();
if (pathJar.toLowerCase().contains(".jar")) {
return true;
} else {
return false;
}
} catch (Exception e) {
return false;
}
}
private static String getPathJar() {
try {
final URI jarUriPath =
Application.class.getResource(Application.class.getSimpleName() + ".class").toURI();
String jarStringPath = jarUriPath.toString().replace("jar:", "");
String jarCleanPath = Paths.get(new URI(jarStringPath)).toString();
if (jarCleanPath.toLowerCase().contains(".jar")) {
return jarCleanPath.substring(0, jarCleanPath.lastIndexOf(".jar") + 4);
} else {
return null;
}
} catch (Exception e) {
return null;
}
}
}
Something that is frustrating is that when you are developing in Eclipse MyClass.class.getProtectionDomain().getCodeSource().getLocation() returns the /bin directory which is great, but when you compile it to a jar, the path includes the /myjarname.jar part which gives you illegal file names.
To have the code work both in the ide and once it is compiled to a jar, I use the following piece of code:
URL applicationRootPathURL = getClass().getProtectionDomain().getCodeSource().getLocation();
File applicationRootPath = new File(applicationRootPathURL.getPath());
File myFile;
if(applicationRootPath.isDirectory()){
myFile = new File(applicationRootPath, "filename");
}
else{
myFile = new File(applicationRootPath.getParentFile(), "filename");
}
Not really sure about the others but in my case it didn't work with a "Runnable jar" and i got it working by fixing codes together from phchen2 answer and another from this link :How to get the path of a running JAR file?
The code:
String path=new java.io.File(Server.class.getProtectionDomain()
.getCodeSource()
.getLocation()
.getPath())
.getAbsolutePath();
path=path.substring(0, path.lastIndexOf("."));
path=path+System.getProperty("java.class.path");
Have tried several of the solutions up there but none yielded correct results for the (probably special) case that the runnable jar has been exported with "Packaging external libraries" in Eclipse. For some reason all solutions based on the ProtectionDomain do result in null in that case.
From combining some solutions above I managed to achieve the following working code:
String surroundingJar = null;
// gets the path to the jar file if it exists; or the "bin" directory if calling from Eclipse
String jarDir = new File(ClassLoader.getSystemClassLoader().getResource(".").getPath()).getAbsolutePath();
// gets the "bin" directory if calling from eclipse or the name of the .jar file alone (without its path)
String jarFileFromSys = System.getProperty("java.class.path").split(";")[0];
// If both are equal that means it is running from an IDE like Eclipse
if (jarFileFromSys.equals(jarDir))
{
System.out.println("RUNNING FROM IDE!");
// The path to the jar is the "bin" directory in that case because there is no actual .jar file.
surroundingJar = jarDir;
}
else
{
// Combining the path and the name of the .jar file to achieve the final result
surroundingJar = jarDir + jarFileFromSys.substring(1);
}
System.out.println("JAR File: " + surroundingJar);
The above methods didn't work for me in my Spring environment, since Spring shades the actual classes into a package called BOOT-INF, thus not the actual location of the running file. I found another way to retrieve the running file through the Permissions object which have been granted to the running file:
public static Path getEnclosingDirectory() {
return Paths.get(FileUtils.class.getProtectionDomain().getPermissions()
.elements().nextElement().getName()).getParent();
}
Mention that it is checked only in Windows but i think it works perfect on other Operating Systems [Linux,MacOs,Solaris] :).
I had 2 .jar files in the same directory . I wanted from the one .jar file to start the other .jar file which is in the same directory.
The problem is that when you start it from the cmd the current directory is system32.
Warnings!
The below seems to work pretty well in all the test i have done even
with folder name ;][[;'57f2g34g87-8+9-09!2##!$%^^&() or ()%&$%^##
it works well.
I am using the ProcessBuilder with the below as following:
🍂..
//The class from which i called this was the class `Main`
String path = getBasePathForClass(Main.class);
String applicationPath= new File(path + "application.jar").getAbsolutePath();
System.out.println("Directory Path is : "+applicationPath);
//Your know try catch here
//Mention that sometimes it doesn't work for example with folder `;][[;'57f2g34g87-8+9-09!2##!$%^^&()`
ProcessBuilder builder = new ProcessBuilder("java", "-jar", applicationPath);
builder.redirectErrorStream(true);
Process process = builder.start();
//...code
🍂getBasePathForClass(Class<?> classs):
/**
* Returns the absolute path of the current directory in which the given
* class
* file is.
*
* #param classs
* #return The absolute path of the current directory in which the class
* file is.
* #author GOXR3PLUS[StackOverFlow user] + bachden [StackOverFlow user]
*/
public static final String getBasePathForClass(Class<?> classs) {
// Local variables
File file;
String basePath = "";
boolean failed = false;
// Let's give a first try
try {
file = new File(classs.getProtectionDomain().getCodeSource().getLocation().toURI().getPath());
if (file.isFile() || file.getPath().endsWith(".jar") || file.getPath().endsWith(".zip")) {
basePath = file.getParent();
} else {
basePath = file.getPath();
}
} catch (URISyntaxException ex) {
failed = true;
Logger.getLogger(classs.getName()).log(Level.WARNING,
"Cannot firgue out base path for class with way (1): ", ex);
}
// The above failed?
if (failed) {
try {
file = new File(classs.getClassLoader().getResource("").toURI().getPath());
basePath = file.getAbsolutePath();
// the below is for testing purposes...
// starts with File.separator?
// String l = local.replaceFirst("[" + File.separator +
// "/\\\\]", "")
} catch (URISyntaxException ex) {
Logger.getLogger(classs.getName()).log(Level.WARNING,
"Cannot firgue out base path for class with way (2): ", ex);
}
}
// fix to run inside eclipse
if (basePath.endsWith(File.separator + "lib") || basePath.endsWith(File.separator + "bin")
|| basePath.endsWith("bin" + File.separator) || basePath.endsWith("lib" + File.separator)) {
basePath = basePath.substring(0, basePath.length() - 4);
}
// fix to run inside netbeans
if (basePath.endsWith(File.separator + "build" + File.separator + "classes")) {
basePath = basePath.substring(0, basePath.length() - 14);
}
// end fix
if (!basePath.endsWith(File.separator)) {
basePath = basePath + File.separator;
}
return basePath;
}
This code worked for me:
private static String getJarPath() throws IOException, URISyntaxException {
File f = new File(LicensingApp.class.getProtectionDomain().().getLocation().toURI());
String jarPath = f.getCanonicalPath().toString();
String jarDir = jarPath.substring( 0, jarPath.lastIndexOf( File.separator ));
return jarDir;
}
The getProtectionDomain approach might not work sometimes e.g. when you have to find the jar for some of the core java classes (e.g in my case StringBuilder class within IBM JDK), however following works seamlessly:
public static void main(String[] args) {
System.out.println(findSource(MyClass.class));
// OR
System.out.println(findSource(String.class));
}
public static String findSource(Class<?> clazz) {
String resourceToSearch = '/' + clazz.getName().replace(".", "/") + ".class";
java.net.URL location = clazz.getResource(resourceToSearch);
String sourcePath = location.getPath();
// Optional, Remove junk
return sourcePath.replace("file:", "").replace("!" + resourceToSearch, "");
}
I have another way to get the String location of a class.
URL path = Thread.currentThread().getContextClassLoader().getResource("");
Path p = Paths.get(path.toURI());
String location = p.toString();
The output String will have the form of
C:\Users\Administrator\new Workspace\...
The spaces and other characters are handled, and in the form without file:/. So will be easier to use.

Reading Directory Contents From a JAR file

I am trying to write a code in a webapp, where I have a JAR file in my classpath. The objective is to check if the directory exists in the JAR. If yes, I need to save the all the contents of the files inside the JAR's directory in a HashMap<String, String>. The Key being the file name and the value being the contents of each file.
File directory = new File(getClass().getClassLoader().getResource(directoryPath).getPath());
System.out.println("PATH IS: " + directory.getPath());
// Check if dirPth exists and is a valid directory
if (!directory.isDirectory()) {
throw new AccessException("Directory \"" + directoryPath + "\" not valid");
}
// Obtain a list of all files under the dirPath
File [] fileList = directory.listFiles();
for (File file : fileList) {
if (file.isFile()) {
// Read the file
BufferedReader br = new BufferedReader(new FileReader(file));
String line = null;
StringBuilder sb = new StringBuilder();
while ((line = br.readLine()) != null) {
sb.append(line);
}
br.close();
// Store the file data in the hash
entry.put(file.getName(), sb.toString);
}
}
The output of the direcotry.getPath() is:
file:\H:\apache-tomcat-9.0.27\lib\myConfigurationFiles.jar!\META-INF\Maintenance\xmlFiles\secondary
which is the right folder I am looking for.
Here the Map object is the "entry".
Now I am not sure why direcotry.isDirectory() returns false. Shouldn't it return true?
Now since its not crossing the first exception. I have no idea how it will behave after that. Any help would be appreciated.
getClass() is the wrong approach for jobs like this; it breaks if anybody subclasses. The proper way is to use MyClassName.class instead.
getClassLoader().getResource() is also the wrong approach; this breaks in exotic but possible cases where getClassLoader() returns null. Just use getResource and slightly change the path (add a leading slash, or, write the path relative to your class file).
You're turning the string file:\H:\apache-tomcat-9.0.27\lib\myConfigurationFiles.jar!\META-INF\Maintenance\xmlFiles\secondary into a filename and then asking if it is a directory. Of course it isn't; that isn't even a file. You need to do some string manipulation to extract the actual file out of it: You want just H:\apache-tomcat-9.0.27\lib\myConfigurationFiles.jar, feed that to the java.nio.file API, and then use that to ask if it is a file (it will never be a directory; jars are not directories).
Note that this will not work if the resource you're reading from isn't a jar. Note that the class loading API is abstracted: You could find yourself in the scenario where source files are generated from scratch or loaded out of a DB, with more exotic URLs being produced by the getResource method to boot. Thus, this kind of code simply won't work then. Make sure that's okay first.
Thus:
String urlAsString = MyClassName.class.getResource("MyClassName.class").toString(); // produces a link to yourself.
int start = urlAsString.startsWith("file:jar:") ? 8 : urlAsString.startsWith("file:") ? 4 : 0;
int end = urlAsString.lastIndexOf('!');
String jarFileLoc = urlAsString.substring(start, end);
if you want this to apply to actual directories (class files and such can come from dirs instead of files), you could do:
var map = new HashMap<String, String>();
Path root = Paths.get(jarFileLoc);
Files.walkFileTree(root, new SimpleFileVisitor<Path>() {
public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {
String content = new String(Files.readAllBytes(file), StandardCharsets.UTF_8);
map.put(root.relativize(file), content);
}
});
for a jar, which is really just a zip, it'll be more like:
var map = new HashMap<String, String>();
Path root = Paths.get(jarFileLoc);
try (var fileIn = Files.newInputStream(root)) {
ZipInputStream zip = new ZipInputStream(fileIn);
for (ZipEntry entry = zip.getNextEntry(); entry != null; entry = zip.getNextEntry()) {
String content = new String(zip.readAllBytes(), StandardCharsets.UTF_8);
map.put(entry.getName(), content);
}
}
Make sure you know what charsets are and that UTF_8 is correct here.
Given a java.nio.file.Path to the jar you want to search (jarPath), and a String for the absolute directory name within the jar (directory), this may work for you:
Map<String, String> map = new HashMap<>();
try (FileSystem fs = FileSystems.newFileSystem(jarPath, null)) {
Path dir = fs.getPath(directory);
if (Files.exists(dir)) {
Files.walkFileTree(dir, new SimpleFileVisitor<Path>() {
#Override
public FileVisitResult visitFile(Path file, BasicFileAttributes attrs)
throws IOException {
map.put(file.toString(), Files.readString(file));
return super.visitFile(file, attrs);
}
});
}
}
Files.readString is available with Java 11+. For earlier versions, use:
new String(Files.readAllBytes(file), StandardCharsets.UTF_8)

Java check if the application is getting run from a specific phat [duplicate]

Want to improve this post? Provide detailed answers to this question, including citations and an explanation of why your answer is correct. Answers without enough detail may be edited or deleted.
My code runs inside a JAR file, say foo.jar, and I need to know, in the code, in which folder the running foo.jar is.
So, if foo.jar is in C:\FOO\, I want to get that path no matter what my current working directory is.
return new File(MyClass.class.getProtectionDomain().getCodeSource().getLocation()
.toURI()).getPath();
Replace "MyClass" with the name of your class.
Obviously, this will do odd things if your class was loaded from a non-file location.
Best solution for me:
String path = Test.class.getProtectionDomain().getCodeSource().getLocation().getPath();
String decodedPath = URLDecoder.decode(path, "UTF-8");
This should solve the problem with spaces and special characters.
To obtain the File for a given Class, there are two steps:
Convert the Class to a URL
Convert the URL to a File
It is important to understand both steps, and not conflate them.
Once you have the File, you can call getParentFile to get the containing folder, if that is what you need.
Step 1: Class to URL
As discussed in other answers, there are two major ways to find a URL relevant to a Class.
URL url = Bar.class.getProtectionDomain().getCodeSource().getLocation();
URL url = Bar.class.getResource(Bar.class.getSimpleName() + ".class");
Both have pros and cons.
The getProtectionDomain approach yields the base location of the class (e.g., the containing JAR file). However, it is possible that the Java runtime's security policy will throw SecurityException when calling getProtectionDomain(), so if your application needs to run in a variety of environments, it is best to test in all of them.
The getResource approach yields the full URL resource path of the class, from which you will need to perform additional string manipulation. It may be a file: path, but it could also be jar:file: or even something nastier like bundleresource://346.fwk2106232034:4/foo/Bar.class when executing within an OSGi framework. Conversely, the getProtectionDomain approach correctly yields a file: URL even from within OSGi.
Note that both getResource("") and getResource(".") failed in my tests, when the class resided within a JAR file; both invocations returned null. So I recommend the #2 invocation shown above instead, as it seems safer.
Step 2: URL to File
Either way, once you have a URL, the next step is convert to a File. This is its own challenge; see Kohsuke Kawaguchi's blog post about it for full details, but in short, you can use new File(url.toURI()) as long as the URL is completely well-formed.
Lastly, I would highly discourage using URLDecoder. Some characters of the URL, : and / in particular, are not valid URL-encoded characters. From the URLDecoder Javadoc:
It is assumed that all characters in the encoded string are one of the following: "a" through "z", "A" through "Z", "0" through "9", and "-", "_", ".", and "*". The character "%" is allowed but is interpreted as the start of a special escaped sequence.
...
There are two possible ways in which this decoder could deal with illegal strings. It could either leave illegal characters alone or it could throw an IllegalArgumentException. Which approach the decoder takes is left to the implementation.
In practice, URLDecoder generally does not throw IllegalArgumentException as threatened above. And if your file path has spaces encoded as %20, this approach may appear to work. However, if your file path has other non-alphameric characters such as + you will have problems with URLDecoder mangling your file path.
Working code
To achieve these steps, you might have methods like the following:
/**
* Gets the base location of the given class.
* <p>
* If the class is directly on the file system (e.g.,
* "/path/to/my/package/MyClass.class") then it will return the base directory
* (e.g., "file:/path/to").
* </p>
* <p>
* If the class is within a JAR file (e.g.,
* "/path/to/my-jar.jar!/my/package/MyClass.class") then it will return the
* path to the JAR (e.g., "file:/path/to/my-jar.jar").
* </p>
*
* #param c The class whose location is desired.
* #see FileUtils#urlToFile(URL) to convert the result to a {#link File}.
*/
public static URL getLocation(final Class<?> c) {
if (c == null) return null; // could not load the class
// try the easy way first
try {
final URL codeSourceLocation =
c.getProtectionDomain().getCodeSource().getLocation();
if (codeSourceLocation != null) return codeSourceLocation;
}
catch (final SecurityException e) {
// NB: Cannot access protection domain.
}
catch (final NullPointerException e) {
// NB: Protection domain or code source is null.
}
// NB: The easy way failed, so we try the hard way. We ask for the class
// itself as a resource, then strip the class's path from the URL string,
// leaving the base path.
// get the class's raw resource path
final URL classResource = c.getResource(c.getSimpleName() + ".class");
if (classResource == null) return null; // cannot find class resource
final String url = classResource.toString();
final String suffix = c.getCanonicalName().replace('.', '/') + ".class";
if (!url.endsWith(suffix)) return null; // weird URL
// strip the class's path from the URL string
final String base = url.substring(0, url.length() - suffix.length());
String path = base;
// remove the "jar:" prefix and "!/" suffix, if present
if (path.startsWith("jar:")) path = path.substring(4, path.length() - 2);
try {
return new URL(path);
}
catch (final MalformedURLException e) {
e.printStackTrace();
return null;
}
}
/**
* Converts the given {#link URL} to its corresponding {#link File}.
* <p>
* This method is similar to calling {#code new File(url.toURI())} except that
* it also handles "jar:file:" URLs, returning the path to the JAR file.
* </p>
*
* #param url The URL to convert.
* #return A file path suitable for use with e.g. {#link FileInputStream}
* #throws IllegalArgumentException if the URL does not correspond to a file.
*/
public static File urlToFile(final URL url) {
return url == null ? null : urlToFile(url.toString());
}
/**
* Converts the given URL string to its corresponding {#link File}.
*
* #param url The URL to convert.
* #return A file path suitable for use with e.g. {#link FileInputStream}
* #throws IllegalArgumentException if the URL does not correspond to a file.
*/
public static File urlToFile(final String url) {
String path = url;
if (path.startsWith("jar:")) {
// remove "jar:" prefix and "!/" suffix
final int index = path.indexOf("!/");
path = path.substring(4, index);
}
try {
if (PlatformUtils.isWindows() && path.matches("file:[A-Za-z]:.*")) {
path = "file:/" + path.substring(5);
}
return new File(new URL(path).toURI());
}
catch (final MalformedURLException e) {
// NB: URL is not completely well-formed.
}
catch (final URISyntaxException e) {
// NB: URL is not completely well-formed.
}
if (path.startsWith("file:")) {
// pass through the URL as-is, minus "file:" prefix
path = path.substring(5);
return new File(path);
}
throw new IllegalArgumentException("Invalid URL: " + url);
}
You can find these methods in the SciJava Common library:
org.scijava.util.ClassUtils
org.scijava.util.FileUtils.
You can also use:
CodeSource codeSource = YourMainClass.class.getProtectionDomain().getCodeSource();
File jarFile = new File(codeSource.getLocation().toURI().getPath());
String jarDir = jarFile.getParentFile().getPath();
Use ClassLoader.getResource() to find the URL for your current class.
For example:
package foo;
public class Test
{
public static void main(String[] args)
{
ClassLoader loader = Test.class.getClassLoader();
System.out.println(loader.getResource("foo/Test.class"));
}
}
(This example taken from a similar question.)
To find the directory, you'd then need to take apart the URL manually. See the JarClassLoader tutorial for the format of a jar URL.
I'm surprised to see that none recently proposed to use Path. Here follows a citation: "The Path class includes various methods that can be used to obtain information about the path, access elements of the path, convert the path to other forms, or extract portions of a path"
Thus, a good alternative is to get the Path objest as:
Path path = Paths.get(Test.class.getProtectionDomain().getCodeSource().getLocation().toURI());
The only solution that works for me on Linux, Mac and Windows:
public static String getJarContainingFolder(Class aclass) throws Exception {
CodeSource codeSource = aclass.getProtectionDomain().getCodeSource();
File jarFile;
if (codeSource.getLocation() != null) {
jarFile = new File(codeSource.getLocation().toURI());
}
else {
String path = aclass.getResource(aclass.getSimpleName() + ".class").getPath();
String jarFilePath = path.substring(path.indexOf(":") + 1, path.indexOf("!"));
jarFilePath = URLDecoder.decode(jarFilePath, "UTF-8");
jarFile = new File(jarFilePath);
}
return jarFile.getParentFile().getAbsolutePath();
}
If you are really looking for a simple way to get the folder in which your JAR is located you should use this implementation.
Solutions like this are hard to find and many solutions are no longer supported, many others provide the path of the file instead of the actual directory. This is easier than other solutions you are going to find and works for java version 1.12.
new File(".").getCanonicalPath()
Gathering the Input from other answers this is a simple one too:
String localPath=new File(getClass().getProtectionDomain().getCodeSource().getLocation().toURI()).getParentFile().getPath()+"\\";
Both will return a String with this format:
"C:\Users\User\Desktop\Folder\"
In a simple and concise line.
I had the the same problem and I solved it that way:
File currentJavaJarFile = new File(Main.class.getProtectionDomain().getCodeSource().getLocation().getPath());
String currentJavaJarFilePath = currentJavaJarFile.getAbsolutePath();
String currentRootDirectoryPath = currentJavaJarFilePath.replace(currentJavaJarFile.getName(), "");
I hope I was of help to you.
Here's upgrade to other comments, that seem to me incomplete for the specifics of
using a relative "folder" outside .jar file (in the jar's same
location):
String path =
YourMainClassName.class.getProtectionDomain().
getCodeSource().getLocation().getPath();
path =
URLDecoder.decode(
path,
"UTF-8");
BufferedImage img =
ImageIO.read(
new File((
new File(path).getParentFile().getPath()) +
File.separator +
"folder" +
File.separator +
"yourfile.jpg"));
For getting the path of running jar file I have studied the above solutions and tried all methods which exist some difference each other. If these code are running in Eclipse IDE they all should be able to find the path of the file including the indicated class and open or create an indicated file with the found path.
But it is tricky, when run the runnable jar file directly or through the command line, it will be failed as the path of jar file gotten from the above methods will give an internal path in the jar file, that is it always gives a path as
rsrc:project-name (maybe I should say that it is the package name of the main class file - the indicated class)
I can not convert the rsrc:... path to an external path, that is when run the jar file outside the Eclipse IDE it can not get the path of jar file.
The only possible way for getting the path of running jar file outside Eclipse IDE is
System.getProperty("java.class.path")
this code line may return the living path (including the file name) of the running jar file (note that the return path is not the working directory), as the java document and some people said that it will return the paths of all class files in the same directory, but as my tests if in the same directory include many jar files, it only return the path of running jar (about the multiple paths issue indeed it happened in the Eclipse).
Other answers seem to point to the code source which is Jar file location which is not a directory.
Use
return new File(MyClass.class.getProtectionDomain().getCodeSource().getLocation().toURI().getPath()).getParentFile();
the selected answer above is not working if you run your jar by click on it from Gnome desktop environment (not from any script or terminal).
Instead, I have fond that the following solution is working everywhere:
try {
return URLDecoder.decode(ClassLoader.getSystemClassLoader().getResource(".").getPath(), "UTF-8");
} catch (UnsupportedEncodingException e) {
return "";
}
I had to mess around a lot before I finally found a working (and short) solution.
It is possible that the jarLocation comes with a prefix like file:\ or jar:file\, which can be removed by using String#substring().
URL jarLocationUrl = MyClass.class.getProtectionDomain().getCodeSource().getLocation();
String jarLocation = new File(jarLocationUrl.toString()).getParent();
For the jar file path:
String jarPath = new File(MyClass.class.getProtectionDomain().getCodeSource().getLocation()
.toURI()).getPath();
For getting the directory path of that jar file:
String dirPath = new File(MyClass.class.getProtectionDomain().getCodeSource().getLocation()
.toURI()).getParent();
The results of the two lines above are like this:
/home/user/MyPrograms/myapp/myjar.jar (value of jarPath)
/home/user/MyPrograms/myapp (value of dirPath)
public static String dir() throws URISyntaxException
{
URI path=Main.class.getProtectionDomain().getCodeSource().getLocation().toURI();
String name= Main.class.getPackage().getName()+".jar";
String path2 = path.getRawPath();
path2=path2.substring(1);
if (path2.contains(".jar"))
{
path2=path2.replace(name, "");
}
return path2;}
Works good on Windows
I tried to get the jar running path using
String folder = MyClassName.class.getProtectionDomain().getCodeSource().getLocation().getPath();
c:\app>java -jar application.jar
Running the jar application named "application.jar", on Windows in the folder "c:\app", the value of the String variable "folder" was "\c:\app\application.jar" and I had problems testing for path's correctness
File test = new File(folder);
if(file.isDirectory() && file.canRead()) { //always false }
So I tried to define "test" as:
String fold= new File(folder).getParentFile().getPath()
File test = new File(fold);
to get path in a right format like "c:\app" instead of "\c:\app\application.jar" and I noticed that it work.
The simplest solution is to pass the path as an argument when running the jar.
You can automate this with a shell script (.bat in Windows, .sh anywhere else):
java -jar my-jar.jar .
I used . to pass the current working directory.
UPDATE
You may want to stick the jar file in a sub-directory so users don't accidentally click it. Your code should also check to make sure that the command line arguments have been supplied, and provide a good error message if the arguments are missing.
Actually here is a better version - the old one failed if a folder name had a space in it.
private String getJarFolder() {
// get name and path
String name = getClass().getName().replace('.', '/');
name = getClass().getResource("/" + name + ".class").toString();
// remove junk
name = name.substring(0, name.indexOf(".jar"));
name = name.substring(name.lastIndexOf(':')-1, name.lastIndexOf('/')+1).replace('%', ' ');
// remove escape characters
String s = "";
for (int k=0; k<name.length(); k++) {
s += name.charAt(k);
if (name.charAt(k) == ' ') k += 2;
}
// replace '/' with system separator char
return s.replace('/', File.separatorChar);
}
As for failing with applets, you wouldn't usually have access to local files anyway. I don't know much about JWS but to handle local files might it not be possible to download the app.?
String path = getClass().getResource("").getPath();
The path always refers to the resource within the jar file.
Try this:
String path = new File("").getAbsolutePath();
This code worked for me to identify if the program is being executed inside a JAR file or IDE:
private static boolean isRunningOverJar() {
try {
String pathJar = Application.class.getResource(Application.class.getSimpleName() + ".class").getFile();
if (pathJar.toLowerCase().contains(".jar")) {
return true;
} else {
return false;
}
} catch (Exception e) {
return false;
}
}
If I need to get the Windows full path of JAR file I am using this method:
private static String getPathJar() {
try {
final URI jarUriPath =
Application.class.getResource(Application.class.getSimpleName() + ".class").toURI();
String jarStringPath = jarUriPath.toString().replace("jar:", "");
String jarCleanPath = Paths.get(new URI(jarStringPath)).toString();
if (jarCleanPath.toLowerCase().contains(".jar")) {
return jarCleanPath.substring(0, jarCleanPath.lastIndexOf(".jar") + 4);
} else {
return null;
}
} catch (Exception e) {
log.error("Error getting JAR path.", e);
return null;
}
}
My complete code working with a Spring Boot application using CommandLineRunner implementation, to ensure that the application always be executed within of a console view (Double clicks by mistake in JAR file name), I am using the next code:
#SpringBootApplication
public class Application implements CommandLineRunner {
public static void main(String[] args) throws IOException {
Console console = System.console();
if (console == null && !GraphicsEnvironment.isHeadless() && isRunningOverJar()) {
Runtime.getRuntime().exec(new String[]{"cmd", "/c", "start", "cmd", "/k",
"java -jar \"" + getPathJar() + "\""});
} else {
SpringApplication.run(Application.class, args);
}
}
#Override
public void run(String... args) {
/*
Additional code here...
*/
}
private static boolean isRunningOverJar() {
try {
String pathJar = Application.class.getResource(Application.class.getSimpleName() + ".class").getFile();
if (pathJar.toLowerCase().contains(".jar")) {
return true;
} else {
return false;
}
} catch (Exception e) {
return false;
}
}
private static String getPathJar() {
try {
final URI jarUriPath =
Application.class.getResource(Application.class.getSimpleName() + ".class").toURI();
String jarStringPath = jarUriPath.toString().replace("jar:", "");
String jarCleanPath = Paths.get(new URI(jarStringPath)).toString();
if (jarCleanPath.toLowerCase().contains(".jar")) {
return jarCleanPath.substring(0, jarCleanPath.lastIndexOf(".jar") + 4);
} else {
return null;
}
} catch (Exception e) {
return null;
}
}
}
Something that is frustrating is that when you are developing in Eclipse MyClass.class.getProtectionDomain().getCodeSource().getLocation() returns the /bin directory which is great, but when you compile it to a jar, the path includes the /myjarname.jar part which gives you illegal file names.
To have the code work both in the ide and once it is compiled to a jar, I use the following piece of code:
URL applicationRootPathURL = getClass().getProtectionDomain().getCodeSource().getLocation();
File applicationRootPath = new File(applicationRootPathURL.getPath());
File myFile;
if(applicationRootPath.isDirectory()){
myFile = new File(applicationRootPath, "filename");
}
else{
myFile = new File(applicationRootPath.getParentFile(), "filename");
}
Not really sure about the others but in my case it didn't work with a "Runnable jar" and i got it working by fixing codes together from phchen2 answer and another from this link :How to get the path of a running JAR file?
The code:
String path=new java.io.File(Server.class.getProtectionDomain()
.getCodeSource()
.getLocation()
.getPath())
.getAbsolutePath();
path=path.substring(0, path.lastIndexOf("."));
path=path+System.getProperty("java.class.path");
Have tried several of the solutions up there but none yielded correct results for the (probably special) case that the runnable jar has been exported with "Packaging external libraries" in Eclipse. For some reason all solutions based on the ProtectionDomain do result in null in that case.
From combining some solutions above I managed to achieve the following working code:
String surroundingJar = null;
// gets the path to the jar file if it exists; or the "bin" directory if calling from Eclipse
String jarDir = new File(ClassLoader.getSystemClassLoader().getResource(".").getPath()).getAbsolutePath();
// gets the "bin" directory if calling from eclipse or the name of the .jar file alone (without its path)
String jarFileFromSys = System.getProperty("java.class.path").split(";")[0];
// If both are equal that means it is running from an IDE like Eclipse
if (jarFileFromSys.equals(jarDir))
{
System.out.println("RUNNING FROM IDE!");
// The path to the jar is the "bin" directory in that case because there is no actual .jar file.
surroundingJar = jarDir;
}
else
{
// Combining the path and the name of the .jar file to achieve the final result
surroundingJar = jarDir + jarFileFromSys.substring(1);
}
System.out.println("JAR File: " + surroundingJar);
The above methods didn't work for me in my Spring environment, since Spring shades the actual classes into a package called BOOT-INF, thus not the actual location of the running file. I found another way to retrieve the running file through the Permissions object which have been granted to the running file:
public static Path getEnclosingDirectory() {
return Paths.get(FileUtils.class.getProtectionDomain().getPermissions()
.elements().nextElement().getName()).getParent();
}
Mention that it is checked only in Windows but i think it works perfect on other Operating Systems [Linux,MacOs,Solaris] :).
I had 2 .jar files in the same directory . I wanted from the one .jar file to start the other .jar file which is in the same directory.
The problem is that when you start it from the cmd the current directory is system32.
Warnings!
The below seems to work pretty well in all the test i have done even
with folder name ;][[;'57f2g34g87-8+9-09!2##!$%^^&() or ()%&$%^##
it works well.
I am using the ProcessBuilder with the below as following:
🍂..
//The class from which i called this was the class `Main`
String path = getBasePathForClass(Main.class);
String applicationPath= new File(path + "application.jar").getAbsolutePath();
System.out.println("Directory Path is : "+applicationPath);
//Your know try catch here
//Mention that sometimes it doesn't work for example with folder `;][[;'57f2g34g87-8+9-09!2##!$%^^&()`
ProcessBuilder builder = new ProcessBuilder("java", "-jar", applicationPath);
builder.redirectErrorStream(true);
Process process = builder.start();
//...code
🍂getBasePathForClass(Class<?> classs):
/**
* Returns the absolute path of the current directory in which the given
* class
* file is.
*
* #param classs
* #return The absolute path of the current directory in which the class
* file is.
* #author GOXR3PLUS[StackOverFlow user] + bachden [StackOverFlow user]
*/
public static final String getBasePathForClass(Class<?> classs) {
// Local variables
File file;
String basePath = "";
boolean failed = false;
// Let's give a first try
try {
file = new File(classs.getProtectionDomain().getCodeSource().getLocation().toURI().getPath());
if (file.isFile() || file.getPath().endsWith(".jar") || file.getPath().endsWith(".zip")) {
basePath = file.getParent();
} else {
basePath = file.getPath();
}
} catch (URISyntaxException ex) {
failed = true;
Logger.getLogger(classs.getName()).log(Level.WARNING,
"Cannot firgue out base path for class with way (1): ", ex);
}
// The above failed?
if (failed) {
try {
file = new File(classs.getClassLoader().getResource("").toURI().getPath());
basePath = file.getAbsolutePath();
// the below is for testing purposes...
// starts with File.separator?
// String l = local.replaceFirst("[" + File.separator +
// "/\\\\]", "")
} catch (URISyntaxException ex) {
Logger.getLogger(classs.getName()).log(Level.WARNING,
"Cannot firgue out base path for class with way (2): ", ex);
}
}
// fix to run inside eclipse
if (basePath.endsWith(File.separator + "lib") || basePath.endsWith(File.separator + "bin")
|| basePath.endsWith("bin" + File.separator) || basePath.endsWith("lib" + File.separator)) {
basePath = basePath.substring(0, basePath.length() - 4);
}
// fix to run inside netbeans
if (basePath.endsWith(File.separator + "build" + File.separator + "classes")) {
basePath = basePath.substring(0, basePath.length() - 14);
}
// end fix
if (!basePath.endsWith(File.separator)) {
basePath = basePath + File.separator;
}
return basePath;
}
This code worked for me:
private static String getJarPath() throws IOException, URISyntaxException {
File f = new File(LicensingApp.class.getProtectionDomain().().getLocation().toURI());
String jarPath = f.getCanonicalPath().toString();
String jarDir = jarPath.substring( 0, jarPath.lastIndexOf( File.separator ));
return jarDir;
}
The getProtectionDomain approach might not work sometimes e.g. when you have to find the jar for some of the core java classes (e.g in my case StringBuilder class within IBM JDK), however following works seamlessly:
public static void main(String[] args) {
System.out.println(findSource(MyClass.class));
// OR
System.out.println(findSource(String.class));
}
public static String findSource(Class<?> clazz) {
String resourceToSearch = '/' + clazz.getName().replace(".", "/") + ".class";
java.net.URL location = clazz.getResource(resourceToSearch);
String sourcePath = location.getPath();
// Optional, Remove junk
return sourcePath.replace("file:", "").replace("!" + resourceToSearch, "");
}
I have another way to get the String location of a class.
URL path = Thread.currentThread().getContextClassLoader().getResource("");
Path p = Paths.get(path.toURI());
String location = p.toString();
The output String will have the form of
C:\Users\Administrator\new Workspace\...
The spaces and other characters are handled, and in the form without file:/. So will be easier to use.

How to find files that match a wildcard string in Java?

This should be really simple. If I have a String like this:
../Test?/sample*.txt
then what is a generally-accepted way to get a list of files that match this pattern? (e.g. it should match ../Test1/sample22b.txt and ../Test4/sample-spiffy.txt but not ../Test3/sample2.blah or ../Test44/sample2.txt)
I've taken a look at org.apache.commons.io.filefilter.WildcardFileFilter and it seems like the right beast but I'm not sure how to use it for finding files in a relative directory path.
I suppose I can look the source for ant since it uses wildcard syntax, but I must be missing something pretty obvious here.
(edit: the above example was just a sample case. I'm looking for the way to parse general paths containing wildcards at runtime. I figured out how to do it based on mmyers' suggestion but it's kind of annoying. Not to mention that the java JRE seems to auto-parse simple wildcards in the main(String[] arguments) from a single argument to "save" me time and hassle... I'm just glad I didn't have non-file arguments in the mix.)
Try FileUtils from Apache commons-io (listFiles and iterateFiles methods):
File dir = new File(".");
FileFilter fileFilter = new WildcardFileFilter("sample*.java");
File[] files = dir.listFiles(fileFilter);
for (int i = 0; i < files.length; i++) {
System.out.println(files[i]);
}
To solve your issue with the TestX folders, I would first iterate through the list of folders:
File[] dirs = new File(".").listFiles(new WildcardFileFilter("Test*.java");
for (int i=0; i<dirs.length; i++) {
File dir = dirs[i];
if (dir.isDirectory()) {
File[] files = dir.listFiles(new WildcardFileFilter("sample*.java"));
}
}
Quite a 'brute force' solution but should work fine. If this doesn't fit your needs, you can always use the RegexFileFilter.
Consider DirectoryScanner from Apache Ant:
DirectoryScanner scanner = new DirectoryScanner();
scanner.setIncludes(new String[]{"**/*.java"});
scanner.setBasedir("C:/Temp");
scanner.setCaseSensitive(false);
scanner.scan();
String[] files = scanner.getIncludedFiles();
You'll need to reference ant.jar (~ 1.3 MB for ant 1.7.1).
Here are examples of listing files by pattern powered by Java 7 nio globbing and Java 8 lambdas:
try (DirectoryStream<Path> dirStream = Files.newDirectoryStream(
Paths.get(".."), "Test?/sample*.txt")) {
dirStream.forEach(path -> System.out.println(path));
}
or
PathMatcher pathMatcher = FileSystems.getDefault()
.getPathMatcher("regex:Test./sample\\w+\\.txt");
try (DirectoryStream<Path> dirStream = Files.newDirectoryStream(
new File("..").toPath(), pathMatcher::matches)) {
dirStream.forEach(path -> System.out.println(path));
}
Since Java 8 you can use Files#find method directly from java.nio.file.
public static Stream<Path> find(Path start,
int maxDepth,
BiPredicate<Path, BasicFileAttributes> matcher,
FileVisitOption... options)
Example usage
Files.find(startingPath,
Integer.MAX_VALUE,
(path, basicFileAttributes) -> path.toFile().getName().matches(".*.pom")
);
Or an example of putting items in a simple string collection:
import java.io.UncheckedIOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Collection;
import java.util.stream.Stream;
final Collection<String> simpleStringCollection = new ArrayList<>();
String wildCardValue = "*.txt";
final Path dir = Paths.get(".");
try {
Stream<Path> results = Files.find(dir,
Integer.MAX_VALUE,
(path, basicFileAttributes) -> path.toFile().getName().matches(wildCardValue)
);
results.forEach(p -> simpleStringCollection.add(p.toString()));
} catch (IOException e) {
throw new UncheckedIOException(e);
}
You could convert your wildcard string to a regular expression and use that with String's matches method. Following your example:
String original = "../Test?/sample*.txt";
String regex = original.replace("?", ".?").replace("*", ".*?");
This works for your examples:
Assert.assertTrue("../Test1/sample22b.txt".matches(regex));
Assert.assertTrue("../Test4/sample-spiffy.txt".matches(regex));
And counter-examples:
Assert.assertTrue(!"../Test3/sample2.blah".matches(regex));
Assert.assertTrue(!"../Test44/sample2.txt".matches(regex));
Might not help you right now, but JDK 7 is intended to have glob and regex file name matching as part of "More NIO Features".
The wildcard library efficiently does both glob and regex filename matching:
http://code.google.com/p/wildcard/
The implementation is succinct -- JAR is only 12.9 kilobytes.
Simple Way without using any external import is to use this method
I created csv files named with billing_201208.csv ,billing_201209.csv ,billing_201210.csv and it looks like working fine.
Output will be the following if files listed above exists
found billing_201208.csv
found billing_201209.csv
found billing_201210.csv
//Use Import ->import java.io.File
public static void main(String[] args) {
String pathToScan = ".";
String target_file ; // fileThatYouWantToFilter
File folderToScan = new File(pathToScan);
File[] listOfFiles = folderToScan.listFiles();
for (int i = 0; i < listOfFiles.length; i++) {
if (listOfFiles[i].isFile()) {
target_file = listOfFiles[i].getName();
if (target_file.startsWith("billing")
&& target_file.endsWith(".csv")) {
//You can add these files to fileList by using "list.add" here
System.out.println("found" + " " + target_file);
}
}
}
}
As posted in another answer, the wildcard library works for both glob and regex filename matching: http://code.google.com/p/wildcard/
I used the following code to match glob patterns including absolute and relative on *nix style file systems:
String filePattern = String baseDir = "./";
// If absolute path. TODO handle windows absolute path?
if (filePattern.charAt(0) == File.separatorChar) {
baseDir = File.separator;
filePattern = filePattern.substring(1);
}
Paths paths = new Paths(baseDir, filePattern);
List files = paths.getFiles();
I spent some time trying to get the FileUtils.listFiles methods in the Apache commons io library (see Vladimir's answer) to do this but had no success (I realise now/think it can only handle pattern matching one directory or file at a time).
Additionally, using regex filters (see Fabian's answer) for processing arbitrary user supplied absolute type glob patterns without searching the entire file system would require some preprocessing of the supplied glob to determine the largest non-regex/glob prefix.
Of course, Java 7 may handle the requested functionality nicely, but unfortunately I'm stuck with Java 6 for now. The library is relatively minuscule at 13.5kb in size.
Note to the reviewers: I attempted to add the above to the existing answer mentioning this library but the edit was rejected. I don't have enough rep to add this as a comment either. Isn't there a better way...
You should be able to use the WildcardFileFilter. Just use System.getProperty("user.dir") to get the working directory. Try this:
public static void main(String[] args) {
File[] files = (new File(System.getProperty("user.dir"))).listFiles(new WildcardFileFilter(args));
//...
}
You should not need to replace * with [.*], assuming wildcard filter uses java.regex.Pattern. I have not tested this, but I do use patterns and file filters constantly.
Glob of Java7: Finding Files. (Sample)
The Apache filter is built for iterating files in a known directory. To allow wildcards in the directory also, you would have to split the path on '\' or '/' and do a filter on each part separately.
Using Java streams only
Path testPath = Paths.get("C:\");
Stream<Path> stream =
Files.find(testPath, 1,
(path, basicFileAttributes) -> {
File file = path.toFile();
return file.getName().endsWith(".java");
});
// Print all files found
stream.forEach(System.out::println);
Why not use do something like:
File myRelativeDir = new File("../../foo");
String fullPath = myRelativeDir.getCanonicalPath();
Sting wildCard = fullPath + File.separator + "*.txt";
// now you have a fully qualified path
Then you won't have to worry about relative paths and can do your wildcarding as needed.
Implement the JDK FileVisitor interface. Here is an example http://wilddiary.com/list-files-matching-a-naming-pattern-java/
Util Method:
public static boolean isFileMatchTargetFilePattern(final File f, final String targetPattern) {
String regex = targetPattern.replace(".", "\\."); //escape the dot first
regex = regex.replace("?", ".?").replace("*", ".*");
return f.getName().matches(regex);
}
jUnit Test:
#Test
public void testIsFileMatchTargetFilePattern() {
String dir = "D:\\repository\\org\my\\modules\\mobile\\mobile-web\\b1605.0.1";
String[] regexPatterns = new String[] {"_*.repositories", "*.pom", "*-b1605.0.1*","*-b1605.0.1", "mobile*"};
File fDir = new File(dir);
File[] files = fDir.listFiles();
for (String regexPattern : regexPatterns) {
System.out.println("match pattern [" + regexPattern + "]:");
for (File file : files) {
System.out.println("\t" + file.getName() + " matches:" + FileUtils.isFileMatchTargetFilePattern(file, regexPattern));
}
}
}
Output:
match pattern [_*.repositories]:
mobile-web-b1605.0.1.pom matches:false
mobile-web-b1605.0.1.war matches:false
_remote.repositories matches:true
match pattern [*.pom]:
mobile-web-b1605.0.1.pom matches:true
mobile-web-b1605.0.1.war matches:false
_remote.repositories matches:false
match pattern [*-b1605.0.1*]:
mobile-web-b1605.0.1.pom matches:true
mobile-web-b1605.0.1.war matches:true
_remote.repositories matches:false
match pattern [*-b1605.0.1]:
mobile-web-b1605.0.1.pom matches:false
mobile-web-b1605.0.1.war matches:false
_remote.repositories matches:false
match pattern [mobile*]:
mobile-web-b1605.0.1.pom matches:true
mobile-web-b1605.0.1.war matches:true
_remote.repositories matches:false
The most simple and easy way by using the io library's File class would be :
String startingdir="The directory name";
String filenameprefix="The file pattern"
File startingDirFile=new File(startingdir);
final File[] listFiles=startingDirFile.listFiles(new FilenameFilter() {
public boolean accept(File arg0,String arg1)
{System.out.println(arg0+arg1);
return arg1.matches(filenameprefix);}
});
System.out.println(Arrays.toString(listFiles));

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