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how to check if output folder is created in java?

I am coming to an issue where I am trying to check if output folder is there and if not create one in my code below. So, I tried doing that way as shown in my code but I dont know if its the proper a way of doing it? can you please advise. thanks for the help.
here is my code:
String outputFolder2 = Printer.getOutputFolder();
File outFileTwo = new File(outputFolder2);
if (!outFileTwo.exists()) {
if (!outFileTwo.mkdir()) {
System.out.println("Failed to make directory for: " + outputFolder2);
}
}

To check if the directory exists:
Files.isDirectory(Paths.get("/the/path"))
To create dir if not exists:
Files.createDirectories(Paths.get("/the/path"))

Simply use
dirPathFileObj.mkdir();
From java.io.File;
If the method detects that no such directory exists, it will automatically create one. Otherwise, it will simply do nothing in terms of File creation.

It's recommended to use the nio package for new code that interacts with files -- it's faster, and easier to code for. Here's how I would write that code, in the form of a junit test that I ran to verify it:
#Test
public void testSomething() {
Path dirPath = Paths.get("C:/I/do/not/exist");
Path filePath = dirPath.resolve("newFile.txt");
try {
assertFalse(Files.exists(dirPath));
dirPath = createDirectories(dirPath);
filePath = Files.createFile(filePath);
assertTrue(Files.exists(filePath));
} catch (IOException iox) {
iox.printStackTrace();
} finally {
try {
Files.deleteIfExists(filePath);
Files.deleteIfExists(dirPath);
} catch (Exception e) {
e.printStackTrace();
}
}
}
This will create C:\I\do\not\exist\newFile.txt, then delete C:\I\do\not\exist, (leaving C:\I\do\not\). For production code, you'd want to remove the asserts and fill in those catch clauses

How to load external properties file with Java without rebuilding the Jar?

I use gradle which structures projects in maven style so I have the following
src/main/java/Hello.java and src/main/resources/test.properties
My Hello.java look like this
public class Hello {
public static void main(String[] args) {
Properties configProperties = new Properties();
ClassLoader classLoader = Hello.class.getClassLoader();
try {
configProperties.load(classLoader.getResourceAsStream("test.properties"));
System.out.println(configProperties.getProperty("first") + " " + configProperties.getProperty("last"));
} catch (IOException e) {
e.printStackTrace();
}
}
}
This works fine. however I want to be able to point to .properties file outside of my project and I want to it to be flexible enough that I can point to any location without rebuilding the jar every time. Is there a way to this without using a File API and passing file path as an argument to the main method?

You can try this one, which will first try to load properties file from project home directory so that you don't have to rebuild jar, if not found then will load from classpath
public class Hello {
public static void main(String[] args) {
String configPath = "test.properties";
if (args.length > 0) {
configPath = args[0];
} else if (System.getenv("CONFIG_TEST") != null) {
configPath = System.getenv("CONFIG_TEST");
}
File file = new File(configPath);
try (InputStream input = file.exists() ? new FileInputStream(file) : Hello.class.getClassLoader().getResourceAsStream(configPath)) {
Properties configProperties = new Properties();
configProperties.load(input);
System.out.println(configProperties.getProperty("first") + " " + configProperties.getProperty("last"));
} catch (IOException ex) {
ex.printStackTrace();
}
}
}
You can send the properties file path as argument or set the path to an environment variable name CONFIG_TEST

Archaius may be complete overkill for such a simple problem, but it is a great way to manage external properties. It is a library for handling configuration: hierarchies of configuration, configuration from property files, configuration from databases, configuration from user defined sources. It may seem complicated, but you will never have to worry about hand-rolling a half-broken solution to configuration again. The Getting Started page has a section on using a local file as the configuration source.

What am I doing wrong with my Dom4j Code?

Hey guys I am working on a load class for my project that loads and pulls a info from a xml files. I have been following a few guides online but I am running into the error java.lang.NoClassDefFoundError: org/jaxen/JaxenException. I know the code is finding the save file because I can print out the name. But when I try to pull out the info I get that error. Snippet of code is below if there is no error in there let me know and Ill post more.
public void LoadProjects()
{
try
{
Files.walk(Paths.get("D:/workspace/Project Program/Projects/")).forEach(filePath ->
{
if(Files.isRegularFile(filePath))
{
System.out.println("Testing");
try
{
SAXReader reader = new SAXReader();
Document document = reader.read(filePath.toFile());
System.out.println(document.getName());
Node node = document.selectSingleNode("///Project/Info");
//String name = node.valueOf("#Name");
//String projNum = node.valueOf("#ProjectNumber");
//node = document.selectSingleNode("//Project/Dates");
//String dueBy = node.valueOf("#DueBy");
//CButton temp = new CButton(name, projNum, dueBy);
//Console.console.AddToList(temp);
}
catch (Exception e)
{
e.printStackTrace();
}
}
});
}
catch(Exception e)
{
e.printStackTrace();
}
}

Did you add the jaxen jar to your servers lib?
Your code seems correct so far but please add as much information as possible from the beginning.
Ff you are using maven:
<dependency>
<groupId>jaxen</groupId>
<artifactId>jaxen</artifactId>
<version>1.1.1</version>
</dependency>

Writing to a file inside of a jar

I am having a problem writing to a .xml file inside of my jar. When I use the following code inside of my Netbeans IDE, no error occurs and it writes to the file just fine.
public void saveSettings(){
Properties prop = new Properties();
FileOutputStream out;
try {
File file = new File(Duct.class.getResource("/Settings.xml").toURI());
out = new FileOutputStream(file);
prop.setProperty("LAST_FILE", getLastFile());
try {
prop.storeToXML(out,null);
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e.toString());
}
try {
out.close();
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e.toString());
}
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e.toString());
}
}
However, when I execute the jar I get an error saying:
IllegalArguementException: uri is not hierachal
Does anyone have an idea of why it's working when i run it in Netbeans, but not working when i execute the jar. Also does anyone have a solution to the problem?

The default class loader expects the classpath to be static (so it can cache heavily), so this approach will not work.
You can put Settings.xml in the file system if you can get a suitable location to put it. This is most likely vendor and platform specific, but can be done.

Add the location of the Settings.xml to the classpath.

I was also struggling with this exception. But finally found out the solution.
When you use .toURI() it returns some thing like
D:/folderName/folderName/Settings.xml
and hence you get the exception "URI is not hierarchical"
To avoid this call the method getPath() on the URI returned, which returns something like
/D:/folderName/folderName/Settings.xml
which is now hierarchical.
In your case, the 5th line in your code should be
File file = new File(Duct.class.getResource("/Settings.xml").toURI().getPath());

Accessing a PDF in Jar

I'm creating a Java application using Netbeans. From the 'Help' Menu item, I'm required to open a PDF file. When I run the application via Netbeans, the document opens, but on opening via the jar file, it isn't opening. Is there anything that can be done?
m_aboutItem.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
Runtime rt = Runtime.getRuntime();
URL link2=getClass().getResource("/newpkg/Documentation.pdf");
String link=link2.toString();
link=link.substring(6);
System.out.println(link);
System.out.println(link2);
String link3="E:/new/build/classes/newpkg/Documentation.pdf";
try {
Process proc = rt.exec("rundll32.exe url.dll,FileProtocolHandler " + link3);
} catch (IOException ex) {
Logger.getLogger(Menubar1.class.getName()).log(Level.SEVERE, null, ex);
}
}
});
The two outputs are as follows:
E:/new/build/classes/newpkg/Documentation.pdf
file:/E:/new/build/classes/newpkg/Documentation.pdf
Consider the above code snippet. On printing 'link',we can see that it is exactly same as the hard coded 'link3'. On using the hard coded 'link3' , the PDF file gets opened from jar application. But when we use link, though it is exactly same as 'link3', the PDF doesn't open.

This is most likely related to the incorrect PDF resource loading. In the IDE you have the PDF file either as part of the project structure or with a directly specified relative path. When a packaged application is running it does not see the resource.
EDIT:
Your code reveals the problem as I have described. The following method could be used to properly identify resource path.
public static URL getURL(final String pathAndFileName) {
return Thread.currentThread().getContextClassLoader().getResource(pathAndFileName);
}
Pls refer to this question, which might provide additional information.

Try out this:
m_aboutItem.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (Desktop.isDesktopSupported()) {
Desktop desktop = Desktop.getDesktop();
URL link2=Menubar1.class.getResource("/newpkg/Documentation.pdf");
String link=link2.toString();
link=link.substring(6);
System.out.println(link);
File file=new File(link);
System.out.println(file);
try {
desktop.open(file);
} catch (IOException ex) {
Logger.getLogger(Menubar1.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
});