通过java代码动态设定Linux系统的环境变量

import java.io.BufferedInputStream;  
import java.io.File;  
import java.io.IOException;  
import java.io.InputStream;  
  
public class ExecuteCmd {  
  
    /** 
     * @param args 
     */  
    public static void main(String[] args) {  
        String[] commonds = {"sh","-c","export JAVA_HOME=/usr/java/jdk;echo $JAVA_HOME"};  
        RunSystemCommand(commonds, null);  
    }  
  
    public static void RunSystemCommand(String[] command, File file) {  
        if (command != null && !command.equals("")) {  
            try {  
                Process ps = null;  
                if (file != null)  
                    ps = Runtime.getRuntime().exec(command, null, file);  
                else  
                    ps = Runtime.getRuntime().exec(command);  
                String message = loadStream(ps.getInputStream());  
                String errorMeg = loadStream(ps.getErrorStream());  
                System.out.println(message);  
                System.out.println("-------");  
                System.out.println(errorMeg);  
                try {  
                    ps.waitFor();  
                } catch (InterruptedException e) {  
                    e.printStackTrace();  
                }  
            } catch (IOException e) {  
                e.printStackTrace();  
            }  
        }  
    }  
  
    private static String loadStream(InputStream in) throws IOException {  
        int ptr = 0;  
        in = new BufferedInputStream(in);  
        StringBuffer buffer = new StringBuffer();  
        while ((ptr = in.read()) != -1) {  
            buffer.append((char) ptr);  
        }  
        return new String(buffer.toString().getBytes("ISO-8859-1"), "GBK");  
    }  
}