Java如何更新properties的多个值

这个例子用使用了propertie的store方法, 他的优点是简单, 不用自己实现IO,但缺点是回丢失注释和原文件的顺序.如果希望保证顺序,请参考 [转]一个保证store内容顺序不变的properties实现http://ygtq0521.iteye.com/blog/1278081

import java.io.*;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

/**
 * Created by IntelliJ IDEA.
 * User: Michael
 * Date: 10/31/11
 * Time: 2:23 PM
 * To change this template use File | Settings | File Templates.
 */
public class UpdateProperties {
    private String pathSeparator = getPathSeparator();


    public static void main(String[] args){

        try{
            String str1 = "/root/yangxm/sf/DSEngine/work/classpath_3.1.3.tra";
            String str2 = "/root/yangxm/sf/DSEngine/work/sandbox-1304059787-0/bin";
            String str3 = "/root/yangxm/sf/DSEngine/work/sandbox-1304059787-0/lib";
 
            File traFile = new File(str1);

            if(!traFile.exists()){
                System.out.println(" tra file not found in dir ...");
            }else{
                new UpdateProperties().runMain(str1);

            }
        }catch (IOException e){
            System.out.println(e);
            // replace logger
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    public  void runMain(String str1, String str2, String str3) throws Exception{

        Properties prop = getTraFile(str1);
        String[] targetVars = {
           "env1.PATH",
           "env2.LD_LIBRARY_PATH", 
           "env3.SHLIB_PATH", 
           "env4.LIBPATH"};

        Map env = getTraFileValue(prop, targetVars);
        Map newEnv = prepareNewEnv(env, str2, str3);
        Properties trafile = updateTraFileValue(prop, newEnv);
        store(trafile, str1, null);
   
    }

    public Properties getTraFile(String properties) throws Exception{
          FileInputStream fis = new FileInputStream(new File(properties));
          Properties nodeTra = new Properties();
          nodeTra.load(fis);
          return nodeTra;
    }


     public String getTraFileValue(Properties prop, String key){
            return prop.getProperty(key);
     }

     public Map<String, String> getTraFileValue(Properties prop, String[] keys){
            HashMap<String, String> env = new HashMap<String, String>();
            for(String key: keys){
                env.put(key, getTraFileValue(prop, key));
            }
            return env;
     }

  

     public boolean isUsingJRE64(Map<String, String> env){
            boolean flag = false;
            if(env.get("tibco.env.PATH").contains("tibcojre64")) {
                flag = true;
            }
                return flag;
     }

     public Map<String, String> prepareNewEnv(Map<String, String> env, String binPath, String libPath){
            Map<String, String> newEnv = new HashMap<String, String>();
            for(String key: env.keySet()){
                 if(key.equals("tibco.env.PATH")){
                    newEnv.put(key, appendNewValue(env.get(key), binPath));
                 }else if(isUsingJRE64(env)){
                    newEnv.put(key, appendNewValue(env.get(key), libPath + "/64" +
                    getPathSeparator() + libPath));
                 }else {
                    newEnv.put(key, appendNewValue(env.get(key), libPath));
                 }
            }
            return newEnv;
     }

     public String appendNewValue(String initValue, String newValue){
            StringBuffer sb = new StringBuffer();
            sb.append(newValue).append(pathSeparator).append(initValue);
            return sb.toString();
     }

 

     public void store(Properties traFile, File file, String comments) throws Exception{
            FileOutputStream fos = new FileOutputStream(file);
            traFile.store(fos, comments);
     }

     public void store(Properties traFile, String filePath, String comments) throws Exception{
            File file = new File(filePath);
            store(traFile, file, comments);
     }

     public Properties updateTraFileValue(Properties prop, String key, String value){
            prop.setProperty(key, value);
            return  prop;
     }

     public Properties updateTraFileValue(Properties prop, Map<String, String> map){
            for(String key: map.keySet()){
                updateTraFileValue(prop, key, map.get(key));
            }
            return  prop;
     }



     private String getPathSeparator(){
            pathSeparator = System.getProperty("path.separator");
            return pathSeparator;
     }




}