java执行bat命令碰到的阻塞问题

使用Java来执行bat命令，如果bat操作时间过长，有可能导致阻塞问题，而且不会执行bat直到关闭服务器。

如：

Runtime r=Runtime.getRuntime();
		Process p=null;
		try{
			String path = "D:/test.bat";

			p = r.exec("cmd.exe /c  "+path);
			p.waitFor();
		}catch(Exception e){ 
			System.out.println("运行错误:"+e.getMessage());
			e.printStackTrace(); 
		}

一般java的exec是没有帮你处理线程阻塞问题的，需要手动处理。

处理后：

Runtime r=Runtime.getRuntime();
		Process p=null;
		try{
			String path = "D:/test.bat";

			p = r.exec("cmd.exe /c  "+path);

			StreamGobbler errorGobbler = new StreamGobbler(p.getErrorStream(), "ERROR");         
         		errorGobbler.start();
        		 StreamGobbler outGobbler = new StreamGobbler(p.getInputStream(), "STDOUT");
		         outGobbler.start();

			p.waitFor();
		}catch(Exception e){ 
			System.out.println("运行错误:"+e.getMessage());
			e.printStackTrace(); 
		}

StreamGobbler 类如下：

package com.test.tool;


import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;


/**
 * 用于处理Runtime.getRuntime().exec产生的错误流及输出流
 */
public class StreamGobbler extends Thread {
	InputStream is;
	String type;
	OutputStream os;

	StreamGobbler(InputStream is, String type) {
		this(is, type, null);
	}

    StreamGobbler(InputStream is, String type, OutputStream redirect) {
        this.is = is;
        this.type = type;
        this.os = redirect;
    }
    
    public void run() {
        InputStreamReader isr = null;
        BufferedReader br = null;
        PrintWriter pw = null;
        try {
            if (os != null)
                pw = new PrintWriter(os);
                
            isr = new InputStreamReader(is);
            br = new BufferedReader(isr);
            String line=null;
            while ( (line = br.readLine()) != null) {
                if (pw != null)
                    pw.println(line);
                System.out.println(type + ">" + line);    
            }
            
            if (pw != null)
                pw.flush();
        } catch (IOException ioe) {
            ioe.printStackTrace();  
        } finally{
        	try {
        		pw.close();
				br.close();
				isr.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
        }
    }
} 

运行bat，就不会阻塞了。