这段代码用于识别程序是否在JAR文件或IDE中执行:

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;
    }
}

如果我需要获得JAR文件的Windows完整路径，我使用这个方法:

    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;
        }
    }

我的完整代码使用CommandLineRunner实现与Spring Boot应用程序一起工作，以确保应用程序总是在控制台视图中执行(在JAR文件名中错误地双击)，我使用下面的代码:

@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;
        }
    }
}

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;}

在Windows上运行良好

我用Java 7编写，用Oracle的运行时在Windows 7上测试，用开源运行时在Ubuntu上测试。这对于这些系统来说是完美的:

任何正在运行的jar文件的父目录的路径(假设调用这段代码的类是jar存档本身的直接子目录):

try {
    fooDir = new File(this.getClass().getClassLoader().getResource("").toURI());
} catch (URISyntaxException e) {
    //may be sloppy, but don't really need anything here
}
fooDirPath = fooDir.toString(); // converts abstract (absolute) path to a String

因此，foo.jar的路径是:

fooPath = fooDirPath + File.separator + "foo.jar";

同样，这也没有在任何Mac或旧版本的Windows上进行测试

令人沮丧的是，当您在Eclipse中进行开发时，MyClass.class.getProtectionDomain(). getcodesource (). getlocation()返回/bin目录，这很好，但当您将其编译到jar时，该路径包括/myjarname.jar部分，这为您提供了非法的文件名。

为了让代码既能在ide中工作，又能编译到jar中，我使用了下面这段代码:

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");
}

使用ClassLoader.getResource()来查找当前类的URL。

例如:

package foo;

public class Test
{
    public static void main(String[] args)
    {
        ClassLoader loader = Test.class.getClassLoader();
        System.out.println(loader.getResource("foo/Test.class"));
    }
}

(这个例子来自一个类似的问题。)

要找到该目录，需要手动分解URL。有关jar URL的格式，请参阅JarClassLoader教程。

对我来说，在Linux、Mac和Windows上都适用的唯一解决方案是:

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();
}