如果执行“ dir”之类的代码,我将获得运行并成功显示输出的代码,但是如果运行“ java -version”或其他Java命令,则不会显示输出。请帮助:
public static void execJob(){
try{
ProcessBuilder pb = new ProcessBuilder("C:\\myPrograms\\jdk1.7.0_79\\bin\\java.exe", "-version");
pb.directory(new File("src"));
Process process = pb.start();
IOThreadHandler outputHandler = new IOThreadHandler(process.getInputStream());
outputHandler.start();
process.waitFor();
System.out.println(outputHandler.getOutput());
}catch(Exception e) {
System.out.println(e.toString());
}
}
private static class IOThreadHandler extends Thread {
private InputStream inputStream;
private StringBuilder output = new StringBuilder();
IOThreadHandler(InputStream inputStream) {
this.inputStream = inputStream;
}
public void run() {
Scanner br = null;
try {
br = new Scanner(new InputStreamReader(inputStream));
String line = null;
while (br.hasNextLine()) {
line = br.nextLine();
output.append(line + System.getProperty("line.separator"));
}
} finally {
br.close();
}
}
[java -version
写入stderr,因此您需要pb.redirectErrorStream(true);
捕获输出。
ProcessBuilder pb = new ProcessBuilder("C:\\myPrograms\\jdk1.7.0_79\\bin\\java.exe", "-version");
pb.redirectErrorStream(true);
...
private InputStream inputStream;
private StringBuilder output = new StringBuilder();
IOThreadHandler(InputStream inputStream) {
this.inputStream = inputStream;
}
public void run() {
try (Scanner br = new Scanner(new InputStreamReader(inputStream))) {
String line = null;
while (br.hasNextLine()) {
line = br.nextLine();
output.append(line).append(System.getProperty("line.separator"));
}
}
}
public String getOutput() {
return output.toString();
}
}````