Java调用外部程序

Java web开发调用外部ffmpeg或mencoder转码...
遇到的问题是ffmpeg或mencoder进程阻塞, 需要停掉tomcat--javaw.exe进程之后才能执行ffmpeg.exe或mencoder.exe

问题的原因: getErrorStream 和 getInputStream 缓冲区没有清空

解决的方法: 同时清空getErrorStream 和 getInputStream 的缓冲区

代码如下:

ProcessBuilder builder = new ProcessBuilder();
builder.command(commend);
Process process = builder.start();
final InputStream is1 = process.getInputStream();
new Thread(new Runnable() {
public void run() {
BufferedReader br = new BufferedReader(new InputStreamReader(is1));
try {
while(br.readLine() != null) ;
} catch (IOException e) {
e.printStackTrace();
}
}
}).start(); // 启动单独的线程来清空process.getInputStream()的缓冲区
InputStream is2 = process.getErrorStream();
BufferedReader br2 = new BufferedReader(new InputStreamReader(is2));
StringBuilder buf = new StringBuilder(); // 保存输出结果流
String line = null;
while((line = br2.readLine()) != null) buf.append(line); 本文出自 “wIsper 把技术做成艺术” 博客，转载请与作者联系！