我有一个程序,我能够从我的代码中成功执行 cmd 命令,但我希望能够从 cmd 命令获得输出。我该怎么做?
到目前为止我的代码是:
第二个.java:
public class Second {
public static void main(String[] args) {
System.out.println("Hello world from Second.java");
}
}
和Main.java
public class Main {
public static void main(String[] args) {
String filename = args[1].substring(0, args[1].length() - 5);
String cmd1 = "javac " + args[1];
String cmd2 = "java " + filename;
Runtime r = Runtime.getRuntime();
Process p = r.exec(cmd1); // i can verify this by being able to see Second.class and running it successfully
p = r.exec(cmd2); // i need to see this output to see if
System.out.println("Done");
}
}
我可以通过检查 Second.class 来检查第一个命令是否成功运行,但是如果这个类产生了一些错误,我怎么才能看到那个错误呢?
最佳答案
您需要流程的 OutputStream (InputStream)(并且您应该使用 ProcessBuilder)...像这样
public static void main(String[] args) {
String filename = args[1].substring(0, args[1].length() - 5);
String cmd1 = "javac " + args[1];
String cmd2 = "java " + filename;
try {
// Use a ProcessBuilder
ProcessBuilder pb = new ProcessBuilder(cmd1);
Process p = pb.start();
InputStream is = p.getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(is));
String line = null;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
int r = p.waitFor(); // Let the process finish.
if (r == 0) { // No error
// run cmd2.
}
} catch (Exception e) {
e.printStackTrace();
}
}
关于java - 从java代码获取cmd命令的输出,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/20803664/