java获得当前路径下的绝对路径的方法，或者某一文件的绝对路径

import java.net.URL;  
import java.security.CodeSource;  
import java.security.ProtectionDomain;  
  
public class TestPath {  
  
    public static void main(String[] args) {  
        ProtectionDomain domain = TestPath.class.getProtectionDomain();  
        CodeSource codeSource = domain.getCodeSource();  
        URL location = codeSource.getLocation();  
        String path = location.getPath();  
        System.out.println(path);  
          
        URL url = TestPath.class.getClassLoader().getResource("log4j.xml");  
        String aurl = url.getPath();  
        System.out.println(aurl);  
  
        URL pathUrl = TestPath.class.getResource("");  
        System.out.println(pathUrl.getPath());  
    }  
  
}