java.lang.Process 阻塞问题

Process 类型对象的 waitFor() 方法的时候当前线程会被阻塞掉,因为InputStream in = Process.getInputStream();或 InputStream err = Process.getErrorStream(); 这2个流中的一个会被阻塞住,所以解决的办法可以是用多线程来解决,可以参看http://www.javaworld.com/javaworld/jw-12-2000/jw-1229-traps_p.html 。

但还有另一种方法可以尝试,

Java代码

String[] cmds = {...};//command and arg
ProcessBuilder builder = new ProcessBuilder(cmds);
//both read inputstream and errstream
builder.redirectErrorStream(true);
Process process = builder.start();
BufferedReader br = new BufferedReader(new InputStreamReader(process
.getInputStream()));
String readLine = br.readLine();
while (readLine != null) {
System.out.println(readLine);
readLine = br.readLine();
}
int resultValue = process.waitFor();

String[] cmds = {...};//command and arg
ProcessBuilder builder = new ProcessBuilder(cmds);
//both read inputstream and errstream
builder.redirectErrorStream(true);
Process process = builder.start();
BufferedReader br = new BufferedReader(new InputStreamReader(process
.getInputStream()));
String readLine = br.readLine();
while (readLine != null) {
System.out.println(readLine);
readLine = br.readLine();
}
int resultValue = process.waitFor();

builder.redirectErrorStream(true); 和BufferedReader br = new BufferedReader(new InputStreamReader(process.getInputStream())); 这样使用就可以在一个线程中执行,而保证不被阻塞住。

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