1. 技术文章
  2. Getting the Current Working Directory in Java

Getting the Current Working Directory in Java

由 |▌冷眼眸甩不掉的悲伤 提交于 2019-11-25 22:19:23

问题


I want to access my current working directory using 

 String current = new java.io.File( \".\" ).getCanonicalPath();
        System.out.println(\"Current dir:\"+current);
 String currentDir = System.getProperty(\"user.dir\");
        System.out.println(\"Current dir using System:\" +currentDir);

OutPut: 

Current dir: C:\\WINDOWS\\system32
Current dir using System: C:\\WINDOWS\\system32

My output is not correct because C drive is not my current directory. Need help in this regard.


回答1:


public class JavaApplication1 {
  public static void main(String[] args) {
       System.out.println("Working Directory = " +
              System.getProperty("user.dir"));
  }
}

This will print a complete absolute path from where your application was initialized.




回答2:


See: http://docs.oracle.com/javase/tutorial/essential/io/pathOps.html

Using java.nio.file.Path and java.nio.file.Paths, you can do the following to show what Java thinks is your current path. This for 7 and on, and uses NIO.

Path currentRelativePath = Paths.get("");
String s = currentRelativePath.toAbsolutePath().toString();
System.out.println("Current relative path is: " + s);

This outputs Current relative path is: /Users/george/NetBeansProjects/Tutorials that in my case is where I ran the class from. Constructing paths in a relative way, by not using a leading separator to indicate you are constructing an absolute path, will use this relative path as the starting point.




回答3:


The following works on Java 7 and up (see here for documentation).

import java.nio.file.Paths;

Paths.get(".").toAbsolutePath().normalize().toString();



回答4:


This will give you the path of your current working directory:

Path path = FileSystems.getDefault().getPath(".");

And this will give you the path to a file called "Foo.txt" in the working directory:

Path path = FileSystems.getDefault().getPath("Foo.txt");

Edit : To obtain an absolute path of current directory:

Path path = FileSystems.getDefault().getPath(".").toAbsolutePath();



回答5:


This is the solution for me

File currentDir = new File("");



回答6:


What makes you think that c:\windows\system32 is not your current directory? The user.dir property is explicitly to be "User's current working directory".

To put it another way, unless you start Java from the command line, c:\windows\system32 probably is your CWD. That is, if you are double-clicking to start your program, the CWD is unlikely to be the directory that you are double clicking from.

Edit: It appears that this is only true for old windows and/or Java versions.




回答7:


I've found this solution in the comments which is better than others and more portable:

String cwd = new File("").getAbsolutePath();



回答8:


Use CodeSource#getLocation().

This works fine in JAR files as well. You can obtain CodeSource by ProtectionDomain#getCodeSource() and the ProtectionDomain in turn can be obtained by Class#getProtectionDomain().

public class Test {
    public static void main(String... args) throws Exception {
        URL location = Test.class.getProtectionDomain().getCodeSource().getLocation();
        System.out.println(location.getFile());
    }
}



回答9:


this.getClass().getClassLoader().getResource("").getPath()



回答10:


generally, as a File object:

File getCwd() {
  return new File("").getAbsoluteFile();
}

you may want to have full qualified string like "D:/a/b/c" doing:

getCwd().getAbsolutePath()



回答11:


I'm on Linux and get same result for both of these approaches:

@Test
public void aaa()
{
    System.err.println(Paths.get("").toAbsolutePath().toString());

    System.err.println(System.getProperty("user.dir"));
}

Paths.get("") docs

System.getProperty("user.dir") docs




回答12:


Using Windows user.dir returns the directory as expected, but NOT when you start your application with elevated rights (run as admin), in that case you get C:\WINDOWS\system32




回答13:


On Linux when you run a jar file from terminal, these both will return the same String: "/home/CurrentUser", no matter, where youre jar file is. It depends just on what current directory are you using with your terminal, when you start the jar file.

Paths.get("").toAbsolutePath().toString();

System.getProperty("user.dir");

If your Class with main would be called MainClass, then try:

MainClass.class.getProtectionDomain().getCodeSource().getLocation().getFile();

This will return a String with absolute path of the jar file.




回答14:


Current working directory is defined differently in different Java implementations. For certain version prior to Java 7 there was no consistent way to get the working directory. You could work around this by launching Java file with -D and defining a variable to hold the info

Something like

java -D com.mycompany.workingDir="%0"

That's not quite right, but you get the idea. Then System.getProperty("com.mycompany.workingDir")...




回答15:


I hope you want to access the current directory including the package i.e. If your Java program is in c:\myApp\com\foo\src\service\MyTest.java and you want to print until c:\myApp\com\foo\src\service then you can try the following code:

String myCurrentDir = System.getProperty("user.dir")
            + File.separator
            + System.getProperty("sun.java.command")
                    .substring(0, System.getProperty("sun.java.command").lastIndexOf("."))
                    .replace(".", File.separator);
    System.out.println(myCurrentDir);

Note: This code is only tested in Windows with Oracle JRE.




回答16:


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;
    }



回答17:


assume that you're trying to run your project inside eclipse, or netbean or stand alone from command line. I have write a method to fix it

public static final String getBasePathForClass(Class<?> clazz) {
    File file;
    try {
        String basePath = null;
        file = new File(clazz.getProtectionDomain().getCodeSource().getLocation().toURI().getPath());
        if (file.isFile() || file.getPath().endsWith(".jar") || file.getPath().endsWith(".zip")) {
            basePath = file.getParent();
        } else {
            basePath = file.getPath();
        }
        // 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 netbean
        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;
    } catch (URISyntaxException e) {
        throw new RuntimeException("Cannot firgue out base path for class: " + clazz.getName());
    }
}

To use, everywhere you want to get base path to read file, you can pass your anchor class to above method, result may be the thing you need :D

Best,




回答18:


None of the answers posted here worked for me. Here is what did work:

java.nio.file.Paths.get(
  getClass().getProtectionDomain().getCodeSource().getLocation().toURI()
);

Edit: The final version in my code:

URL myURL = getClass().getProtectionDomain().getCodeSource().getLocation();
java.net.URI myURI = null;
try {
    myURI = myURL.toURI();
} catch (URISyntaxException e1) 
{}
return java.nio.file.Paths.get(myURI).toFile().toString()



回答19:


System.getProperty("java.class.path")




回答20:


this is current directory name 

String path="/home/prasad/Desktop/folderName";
File folder = new File(path);
String folderName=folder.getAbsoluteFile().getName();

this is current directory path

String path=folder.getPath();


来源：https://stackoverflow.com/questions/4871051/getting-the-current-working-directory-in-java

标签
java
working-directory
易学教程内所有资源均来自网络或用户发布的内容，如有违反法律规定的内容欢迎反馈！
该文章没有解决你所遇到的问题?点击提问,说说你的问题,让更多的人一起探讨吧!