java如何获取项目的工作目录

使用下面这个PathUtil的getProgramPath()就可以获得当前程序运行的目录。

import java.net.URL;

import java.net.URLDecoder;

class PathUtil {

/**

* Get the env of windir, such as "C:\WINDOWS".

*

* @return the env of windir value.

*/

public static String getWindir() {

return System.getenv("windir");

}

/**

* Get file separator, such as "/" on unix.

*

* @return the separator of file.

*/

public static String getFileSeparator() {

return System.getProperty("file.separator");

}

/**

* Get line separator, such as "\n" on unix.

*

* @return the separator of line.

*/

public static String getLineSeparator() {

return System.getProperty("line.separator");

}

/**

* Get programPath

*

* @return programPath

*/

public static String getProgramPath() {

Class cls = PathUtil.class;

ClassLoader loader = cls.getClassLoader();

//

// Get the full name of the class.

//

String clsName = cls.getName() + ".class";

//

// Get the package that include the class.

//

Package pack = cls.getPackage();

String path = "";

//

// Transform package name to path.

//

if (pack != null) {

String packName = pack.getName();

//

// Get the class's file name.

//

clsName = clsName.substring(packName.length() + 1);

//

// If package is simple transform package name to path directly,

// else transform package name to path by package name's

// constituent.

//

path = packName;

if (path.indexOf(".") > 0) {

path = path.replace(".", "/");

}

path = path + "/";

}

URL url = loader.getResource(path + clsName);

//

// Get path information form the instance of URL.

//

String retPath = url.getPath();

//

// Delete protocol name "file:" form path information.

//

try {

int pos = retPath.indexOf("file:");

if (pos > -1) {

retPath = retPath.substring(pos + 5);

}

//

// Delete the information of class file from the information of

// path.

//

pos = retPath.indexOf(path + clsName);

retPath = retPath.substring(0, pos - 1);

//

// If the class file was packageed into JAR e.g. file, delete the

// file name of the corresponding JAR e.g..

//

if (retPath.endsWith("!")) {

retPath = retPath.substring(0, retPath.lastIndexOf("/"));

}

retPath = URLDecoder.decode(retPath, "utf-8");

} catch (Exception e) {

retPath = null;

e.printStackTrace();

}

return retPath;

}

}

测试类：

public class Test{

public static void main(String args[]){

String s = PathUtil.getProgramPath();我爱编程网

System.out.println(s);

}

}

import java.io.File;

import java.net.URLDecoder;

public class ProjectPath {

private static String rootPath = "";

private ProjectPath() {

init();

}

@SuppressWarnings("deprecation")

private static void init() {

String path = ProjectPath.class.getResource("ProjectPath.class")

.toString();

path = URLDecoder.decode(path);

path.replaceAll("\\\\", "/");

int index = path.indexOf("WEB-INF");

if (index == -1) {

index = path.indexOf("bin");

}

if (index == -1) {

index = path.indexOf("lib");

}

if (index == -1) {

int index2 = path.indexOf("jar!");

if (index2 != -1) {

path = path.substring(0, index2);

System.out.println(path);

System.out.println(File.separator);

index = path.lastIndexOf("/");

System.out.println(index);

}

}

path = path.substring(0, index);

if (path.startsWith("jar")) {

path = path.substring(9);

}

if (path.startsWith("file")) {

path = path.substring(5);

}

if (path.endsWith("/") || path.endsWith("\\")) {

path = path.substring(0, path.length() - 1);

}

// linux环境下第一个/是需要的

String os = System.getProperty("os.name").toLowerCase();

if (os.startsWith("win")) {

path = path.substring(1);

}

rootPath = path;

}

/**

* 获取应用的根目录，路径分隔符为/，路径结尾无/

*

* @return

*/

public static String getProjectPath() {

if ("".equals(rootPath)) {

init();

}

return rootPath;

}

}

你这是用命令行来编译java代码?

找不到目录， 你先看看java代码在什么目录 比如在D盘 code 文件夹下有java代码HelloWorld.java

D:\code\HelloWorld.java

那么命令依次应该是

d:

cd d:\code

javac HelloWorld.java

java HelloWorld

如果还不清楚就留个联系方式帮你看看