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Not able to read resource files from src/test/resources in STS

I created folder src/test/resources/ in root project directory, and inside this I added a file in folder jsons as jsons/server_request.json.
Now I am trying to read this file by calling a the static function in CommonTestUtilityclass given as:
public class CommonTestUtility {
public static String getFileAsString(String fileName) throws IOException {
ClassLoader classLoader = ClassLoader.getSystemClassLoader();
File file = new File(classLoader.getResource(fileName).getFile());
String content = new String(Files.readAllBytes(file.toPath()));
return content;
}
}
Now while calling this function as
class ServerTest {
#Test
void test_loadResource() {
String content = CommonTestUtility.getFileAsString("jsons/server_request.json");
}
}
, It's giving me the error as:
CommonTestUtility - Cannot invoke "java.net.URL.getFile()" because the return value of "java.lang.ClassLoader.getResource(String)" is null.
I tried to include the src/test/resources/ in the run configuration
of Junit ServerTest.java, but still it's not able to find out the
resource
How to resolve this issue?

https://mkyong.com/java/java-read-a-file-from-resources-folder/
This above link might be helpful.
The getResource() method return an URI you need to change
.getFile() function to. toURI().
Simple code
private File getFileFromResource(String fileName) throws URISyntaxException{
ClassLoader classLoader = getClass().getClassLoader();
URL resource = classLoader.getResource(fileName);
if (resource == null) {
throw new IllegalArgumentException("file not found! " + fileName);
} else {
// failed if files have whitespaces or special characters
//return new File(resource.getFile());
return new File(resource.toURI());
}
}

I recreated the same scenario you describe and your code works for me.
Could you double-check that your project looks like mine below? If so, I suspect it might be something with your environment.

Create Leap Motion Java Application (including -Djava.library.path inside jar) [duplicate]

The library in question is Tokyo Cabinet.
I want is to have the native library, JNI library, and all Java API classes in one JAR file to avoid redistribution headaches.
There seems to be an attempt at this at GitHub, but
It does not include the actual native library, only JNI library.
It seems to be specific to Leiningen's native dependencies plugin (it won't work as a redistributable).
The question is, can I bundle everything in one JAR and redistribute it? If yes, how?
P.S.: Yes, I realize it may have portability implications.

It is possible to create a single JAR file with all dependencies including the native JNI libraries for one or more platforms. The basic mechanism is to use System.load(File) to load the library instead of the typical System.loadLibrary(String) which searches the java.library.path system property. This method makes installation much simpler as the user does not have to install the JNI library on his system, at the expense, however, that all platforms might not be supported as the specific library for a platform might not be included in the single JAR file.
The process is as follows:
include the native JNI libraries in the JAR file at a location specific to the platform, for example at NATIVE/${os.arch}/${os.name}/libname.lib
create code in a static initializier of the main class to
calc the current os.arch and os.name
look for the library in the JAR file at the predefined location using Class.getResource(String)
if it exists, extract it to a temp file and load it with System.load(File).
I added functionality to do this for jzmq, the Java bindings of ZeroMQ (shameless plug). The code can be found here. The jzmq code uses a hybrid solution so that if an embedded library cannot be loaded, the code will revert to searching for the JNI library along the java.library.path.

https://www.adamheinrich.com/blog/2012/12/how-to-load-native-jni-library-from-jar/
is great article, which solves my issue ..
In my case I've got the following code for initialize the library:
static {
try {
System.loadLibrary("crypt"); // used for tests. This library in classpath only
} catch (UnsatisfiedLinkError e) {
try {
NativeUtils.loadLibraryFromJar("/natives/crypt.dll"); // during runtime. .DLL within .JAR
} catch (IOException e1) {
throw new RuntimeException(e1);
}
}
}

Take a look at One-JAR. It will wrap your application up in a single jar file with a specialised class loader which handles "jars within jars" among other things.
It handles native (JNI) libraries by unpacking them to a temporary working folder as required.
(Disclaimer: I've never used One-JAR, haven't needed to as yet, just had it bookmarked for a rainy day.)

1) Include the native library into your JAR as a Resource. E. g. with Maven or Gradle, and the standard project layout, put the native library into main/resources directory.
2) Somewhere in static initializers of Java classes, related to this library, put the code like the following:
String libName = "myNativeLib.so"; // The name of the file in resources/ dir
URL url = MyClass.class.getResource("/" + libName);
File tmpDir = Files.createTempDirectory("my-native-lib").toFile();
tmpDir.deleteOnExit();
File nativeLibTmpFile = new File(tmpDir, libName);
nativeLibTmpFile.deleteOnExit();
try (InputStream in = url.openStream()) {
Files.copy(in, nativeLibTmpFile.toPath());
}
System.load(nativeLibTmpFile.getAbsolutePath());

JarClassLoader is a class loader to load classes, native libraries and resources from a single monster JAR and from JARs inside the monster JAR.

Solution for Kotlin:
build.gradle.dsl: copy kotlin runtime (kotlin-stdlib-1.4.0.jar) and native library (librust_kotlin.dylib) to JAR
tasks.withType<Jar> {
manifest {
attributes("Main-Class" to "MainKt")
}
val libs = setOf("kotlin-stdlib-1.4.0.jar")
from(configurations.runtimeClasspath.get()
.filter { it.name in libs }
.map { zipTree(it) })
from("librust_kotlin.dylib")
}
main method: copy library to a temporary file to load it using absolute path
with(createTempFile()) {
deleteOnExit()
val bytes = My::class.java.getResource("librust_kotlin.dylib")
.readBytes()
outputStream().write(bytes)
System.load(path)
}

You will probably have to unjar the native library to the local file system. As far as I know the bit of code that does the native loading looks at the file system.
This code should help get you started (I haven't looked at it in a while, and it is for a different purpose but should do the trick, and I am pretty busy at the moment, but if you have questions just leave a comment and I'll answer as soon as I can).
import java.io.Closeable;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.net.URLDecoder;
import java.security.CodeSource;
import java.security.ProtectionDomain;
import java.util.zip.ZipEntry;
import java.util.zip.ZipException;
import java.util.zip.ZipFile;
public class FileUtils
{
public static String getFileName(final Class<?> owner,
final String name)
throws URISyntaxException,
ZipException,
IOException
{
String fileName;
final URI uri;
try
{
final String external;
final String decoded;
final int pos;
uri = getResourceAsURI(owner.getPackage().getName().replaceAll("\\.", "/") + "/" + name, owner);
external = uri.toURL().toExternalForm();
decoded = external; // URLDecoder.decode(external, "UTF-8");
pos = decoded.indexOf(":/");
fileName = decoded.substring(pos + 1);
}
catch(final FileNotFoundException ex)
{
fileName = null;
}
if(fileName == null || !(new File(fileName).exists()))
{
fileName = getFileNameX(owner, name);
}
return (fileName);
}
private static String getFileNameX(final Class<?> clazz, final String name)
throws UnsupportedEncodingException
{
final URL url;
final String fileName;
url = clazz.getResource(name);
if(url == null)
{
fileName = name;
}
else
{
final String decoded;
final int pos;
decoded = URLDecoder.decode(url.toExternalForm(), "UTF-8");
pos = decoded.indexOf(":/");
fileName = decoded.substring(pos + 1);
}
return (fileName);
}
private static URI getResourceAsURI(final String resourceName,
final Class<?> clazz)
throws URISyntaxException,
ZipException,
IOException
{
final URI uri;
final URI resourceURI;
uri = getJarURI(clazz);
resourceURI = getFile(uri, resourceName);
return (resourceURI);
}
private static URI getJarURI(final Class<?> clazz)
throws URISyntaxException
{
final ProtectionDomain domain;
final CodeSource source;
final URL url;
final URI uri;
domain = clazz.getProtectionDomain();
source = domain.getCodeSource();
url = source.getLocation();
uri = url.toURI();
return (uri);
}
private static URI getFile(final URI where,
final String fileName)
throws ZipException,
IOException
{
final File location;
final URI fileURI;
location = new File(where);
// not in a JAR, just return the path on disk
if(location.isDirectory())
{
fileURI = URI.create(where.toString() + fileName);
}
else
{
final ZipFile zipFile;
zipFile = new ZipFile(location);
try
{
fileURI = extract(zipFile, fileName);
}
finally
{
zipFile.close();
}
}
return (fileURI);
}
private static URI extract(final ZipFile zipFile,
final String fileName)
throws IOException
{
final File tempFile;
final ZipEntry entry;
final InputStream zipStream;
OutputStream fileStream;
tempFile = File.createTempFile(fileName.replace("/", ""), Long.toString(System.currentTimeMillis()));
tempFile.deleteOnExit();
entry = zipFile.getEntry(fileName);
if(entry == null)
{
throw new FileNotFoundException("cannot find file: " + fileName + " in archive: " + zipFile.getName());
}
zipStream = zipFile.getInputStream(entry);
fileStream = null;
try
{
final byte[] buf;
int i;
fileStream = new FileOutputStream(tempFile);
buf = new byte[1024];
i = 0;
while((i = zipStream.read(buf)) != -1)
{
fileStream.write(buf, 0, i);
}
}
finally
{
close(zipStream);
close(fileStream);
}
return (tempFile.toURI());
}
private static void close(final Closeable stream)
{
if(stream != null)
{
try
{
stream.close();
}
catch(final IOException ex)
{
ex.printStackTrace();
}
}
}
}

Create a public folder in internal storage

Sorry for my English, but I want to write in this file because in my opinion is the best.
Now my problem:
I want to create a folder in Internal storage to share with 2 application.
In my app, I downloaded an Apk from my server and I run it.
Before I used external storage and everything worked.
Now I want to use the internal storage for users that don't have an external storage.
I use this:
String folderPath = getFilesDir() + "Dir"
but when i try to run the Apk, it doesn't work, and I can't find this folder on my phone.
Thank you..

From this post :
Correct way:
Create a File for your desired directory (e.g., File path=new
File(getFilesDir(),"myfolder");)
Call mkdirs() on that File to create the directory if it does not exist
Create a File for the output file (e.g., File mypath=new File(path,"myfile.txt");)
Use standard Java I/O to write to that File (e.g., using new BufferedWriter(new FileWriter(mypath)))
Enjoy.
Also to create public file I use :
/**
* Context.MODE_PRIVATE will create the file (or replace a file of the same name) and make it private to your application.
* Other modes available are: MODE_APPEND, MODE_WORLD_READABLE, and MODE_WORLD_WRITEABLE.
*/
public static void createInternalFile(Context theContext, String theFileName, byte[] theData, int theMode)
{
FileOutputStream fos = null;
try {
fos = theContext.openFileOutput(theFileName, theMode);
fos.write(theData);
fos.close();
} catch (FileNotFoundException e) {
Log.e(TAG, "[createInternalFile]" + e.getMessage());
} catch (IOException e) {
Log.e(TAG, "[createInternalFile]" + e.getMessage());
}
}
Just set theMode to MODE_WORLD_WRITEABLE or MODE_WORLD_READABLE (note they are deprecated from api lvl 17).
You can also use theContext.getDir(); but note what doc says :
Retrieve, creating if needed, a new directory in which the application can place its own custom data files. You can use the returned File object to create and access files in this directory. Note that files created through a File object will only be accessible by your own application; you can only set the mode of the entire directory, not of individual files.
Best wishes.

You can create a public into a existing system public folder, there is some public folder accessible from internal storage :
public static String DIRECTORY_MUSIC = "Music";
public static String DIRECTORY_PODCASTS = "Podcasts";
public static String DIRECTORY_RINGTONES = "Ringtones";
public static String DIRECTORY_ALARMS = "Alarms";
public static String DIRECTORY_NOTIFICATIONS = "Notifications";
public static String DIRECTORY_PICTURES = "Pictures";
public static String DIRECTORY_MOVIES = "Movies";
public static String DIRECTORY_DOWNLOADS = "Download";
public static String DIRECTORY_DCIM = "DCIM";
public static String DIRECTORY_DOCUMENTS = "Documents";
To create your folder, use this code :
File myDirectory = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOCUMENTS), "MyPublicFolder");
myDirectory.mkdir();
With this example, a public will be created in Documents and can be visible in any file's explorer app for Android.

try the below
File mydir = context.getDir("Newfolder", Context.MODE_PRIVATE); //Creating an internal dir;
if(!mydir.exists)
{
mydir.mkdirs();
}

This is what i have used and is working fine for me:
String extStorageDirectory = Environment.getExternalStorageDirectory().toString();
File file = new File(extStorageDirectory, fileName);
File parent=file.getParentFile();
if(!parent.exists()){
parent.mkdirs();
}
This will create a new directory if not already present or use the existing if already present.

Include local .json file in Eclipse Android project

I have a local .json file. I don't want it to be on a server, I just want it to be included in my app. I tried to paste it directly into Eclipse in my project, but I got a FileNotFoundException, I also tried to paste it in the workspace folder in Windows Explorer/Finder and got the same exception. Where should I put it?
Thanks!

You should put the file either in the /assets or /res/raw directory of your Android project. From there, you can retrieve it with either: Context.getResources().openRawResource(R.raw.filename) or Context.getResources().getAssets().open("filename").

Put the json file in assets folder, I have used this method like this
public static String jsonToStringFromAssetFolder(String fileName,Context context) throws IOException {
AssetManager manager = context.getAssets();
InputStream file = manager.open(fileName);
byte[] data = new byte[file.available()];
file.read(data);
file.close();
return new String(data);
}
While parsing we can use the method like:
String jsondata= jsonToStringFromAssetFolder(your_filename, your_context);
jsonFileToJavaObjectsParsing(jsondata); // json data to java objects implementation
More Info: Prativa's Blog

Put the file in the assets folder.
You can use the AssetManager open(String fileName) to read the file.

Under /assets in your project folder. If you don't have one, make it.

Copy Asset to Local Storage
I had a very similar need. I had a label template file that I needed to provide a Bluetooth printer configuration so I included it in my assets directory and copied it to the internal storage for later use:
private static final String LABEL_TEMPLATE_FILE_NAME = "RJ_4030_4x3_labels.bin";
InputStream inputStreamOfLabelTemplate = getAssets().open( LABEL_TEMPLATE_ASSET_PATH );
labelTemplateFile = new File( getFilesDir() + LABEL_TEMPLATE_FILE_NAME );
copyInputStreamToFile( inputStreamOfLabelTemplate, labelTemplateFile );
printer.setCustomPaper( labelTemplateFile.getAbsolutePath() );
copyInputStreamToFile Function
// Copy an InputStream to a File.
//
private void copyInputStreamToFile(InputStream in, File file) {
try {
OutputStream out = new FileOutputStream(file);
byte[] buf = new byte[1024];
int len;
while((len=in.read(buf))>0){
out.write(buf,0,len);
}
out.close();
in.close();
} catch (Exception e) {
e.printStackTrace();
}
}

How do I automatically convert all javadoc package.html files into package-info.java files?

We use a lot of legacy package.html files in our project and we want to convert them to package-info.java files. Doing that manually isn't an option (way too many files). Is there a good way to automate that?
We want to convert them for a couple of reasons:
From the javadoc specs: This file is new in JDK 5.0, and is preferred over package.html.
To not mix both types of files in the same codebase
To avoid that Intellij/Eclipse builds put those *.html files in our classes dirs (and possibly in a release binary jars) so they behave like our other normal html resources.

You may need to change the directory separator if you're not running windows. Also, the conversion is a bit of a hack, but it should work. Out of curiosity, how many packages do you have that manual isn't an option?
public class Converter {
public static void main(String[] args) {
File rootDir = new File(".");
renamePackageToPackageInfo(rootDir);
}
private static void renamePackageToPackageInfo(File dir) {
File[] files = dir.listFiles(new FilenameFilter() {
#Override
public boolean accept(File dir, String name) {
return "package.html".equals(name);
}
});
for (File file : files) {
convertFile(file);
}
// now recursively rename all the child directories.
File[] dirs = dir.listFiles(new FileFilter() {
#Override
public boolean accept(File pathname) {
return pathname.isDirectory();
}
});
for (File subdir : dirs) {
renamePackageToPackageInfo(subdir);
}
}
private static void convertFile(File html) {
// determine the FQN package name
String fqpn = getPackageName(html);
// check if package-info.java already exists
File packageInfo = new File(html.getParent(), "package-info.java");
if (packageInfo.exists()) {
System.out.println("package-info.java already exists for package: "+fqpn);
return;
}
// create the i/o streams, and start pumping the data
try {
PrintWriter out = new PrintWriter(packageInfo);
BufferedReader in = new BufferedReader(new FileReader(html));
out.println("/**");
// skip over the headers
while (true) {
String line = in.readLine();
if (line.equalsIgnoreCase("<BODY>"))
break;
}
// now pump the file into the package-info.java file
while (true) {
String line = in.readLine();
if (line.equalsIgnoreCase("</BODY>"))
break;
out.println(" * " + line);
}
out.println("*/");
out.println("package "+fqpn+";");
out.close();
in.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
// queue the package.html file for deletion
//html.deleteOnExit();
}
private static String getPackageName(File file) {
StringBuilder path = new StringBuilder(file.getParent());
// trim the first two characters (./ or .\)
path.delete(0, 2);
// then convert all separators into . (HACK: should use directory separator property)
return path.toString().replaceAll("\\\\", ".");
}
}

The IntelliJ guys have made an intention to do this for all files. It's been resolved and will probably be released in the next IntelliJ release.

To do this in batch mode in IDEA:
In settings, activate the inspection gadget "'package.html' may be converted to 'package-info.java' inspection"
Open a package.html file
You see a banner fix the inspection on top the file
Click on the settings icon at the right on the banner
Select "Run inspection on" >> "Whole project"
Click on "Convert to package-info.java" >> OK
Optionally remove the inappropriate lines (sed -i "/Put #see and #since/d" `find . -name "package-info.java"`)