/**
* read filemap.propreties to initialize file map.
*/
private void initmaps(){
if(filemaps==null){
filemaps=new HashMap();
String filemap=System.getProperty("filemap"); 
//获得filemap.properties文件路径，需要在jvm运行时传入-Dfilemap=[filemap.properties全路径名]，
不要试图使用 classloader.getResource(), 因为getResource里也会使用java.io.File，会产生jvm异常。

if(filemap==null || filemap=="")
return;
this.path = fs.normalize(filemap); 
//准备读取filemap.properties文件。因为使用FileInputStream时，
需要传入一个java.io.File对象，在这暂 时把this.path设为filemap.properties的路径。

this.prefixLength = fs.prefixLength(this.path);
Properties pro=new Properties();
try {

pro.load(new FileInputStream(this)); //读取filemap.properties.

Enumeration enumeration=pro.propertyNames();

while(enumeration.hasMoreElements()){
String sourcepath=(String)enumeration.nextElement(); 
String targetpath=pro.getProperty(sourcepath);
filemaps.put(sourcepath, targetpath); //保存到filemaps静态对象里。
}
} catch(FileNotFoundException e1){
return;
} catch(IOException e2){
return;
}
} 
}

/**
* Get Virutal Path string
* @param name 原UNIX/Linux路径。
* @return 新windows路径。
*/
private String getVirtualPath(String name){
Iterator sources=filemaps.keySet().iterator(); 
while(sources.hasNext()){
String source=(String)sources.next();
if(name.startsWith(source)==true){ 
//当原路径包含filemaps里某一个source路径时，将原路径转换为新的target路径。
String target=(String)filemaps.get(source);
name=target+name.substring(source.length());
}
} 
return name;
}

/**
* Creates a new File instance by converting the given
* pathname string into an abstract pathname. If the given string is
* the empty string, then the result is the empty abstract pathname.
*
* @param pathname A pathname string
* @throws NullPointerException
* If the pathname argument is null
*/
public File(String pathname) {
//new function
initmaps();

if (pathname == null) {
throw new NullPointerException();
}
//new function
pathname=getVirtualPath(pathname);

this.path = fs.normalize(pathname);
this.prefixLength = fs.prefixLength(this.path);
}

public File(String parent, String child) {
//new function
initmaps();

if (child == null) {
throw new NullPointerException();
}
//new function
child=getVirtualPath(child);
parent=getVirtualPath(parent);

if (parent != null) {
if (parent.equals("")) {

this.path = fs.resolve(fs.getDefaultParent(),
fs.normalize(child));
} else {

this.path = fs.resolve(fs.normalize(parent),
fs.normalize(child));
}
} else {
this.path = fs.normalize(child);
}
this.prefixLength = fs.prefixLength(this.path);
}


public File(File parent, String child) {
//new function
initmaps();
child=getVirtualPath(child);

if (child == null) {
throw new NullPointerException();
}
if (parent != null) {
if (parent.path.equals("")) {
this.path = fs.resolve(fs.getDefaultParent(),
fs.normalize(child));
} else {
String parentpath=getVirtualPath(parent.path); 
this.path = fs.resolve(parent.path,
fs.normalize(child));
}
} else {
this.path = fs.normalize(child);
}
this.prefixLength = fs.prefixLength(this.path);
}

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileReader;

public class Test {

/**
* @param args
*/
public static void main(String[] args) {
FileReader filereader;
try {
//打印/usr/WebSphere/AppServer/InstallApp/Test.java
filereader = new FileReader(
"/usr/WebSphere/AppServer/InstallApp/Test.java");
BufferedReader bufferedreader = new BufferedReader(filereader);
String line=null;
while((line=bufferedreader.readLine())!=null)
System.out.println(line);
//遍历/usr/WebSphere/AppServer/InstallApp/Test.java所在的目录下所有文件，并打印文件名。

File fl=new File("/usr/WebSphere/AppServer/InstallApp/Test.java");
String path=fl.getParent();
String[] files=new File(path).list();
for(int i=0;i System.out.println(files);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}