如何在另一個java程序中運行java可執行jar

Question

我知道之前已經問過這個問題，但這些答案並沒有給我一個答案。

我想在我的java程序中執行一個exec jar文件，並將執行jar的輸出變為字符串。 以下是我到目前為止使用的代碼沒有成功。

cmdlink = "java -jar iwtest-mac.jar"+" "+cmd;
            System.out.println(cmdlink);
             Process process = Runtime.getRuntime().exec(cmdlink);
             BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
             while ((reader.readLine()) != null) {
                 st = reader.readLine();  

             }
             process.waitFor();

我試過的另一個代碼如下：

String cmdlink = "iwtest-mac.jar "+cmd;    
          ProcessBuilder pb = new ProcessBuilder("java", "-jar", cmdlink); //cmd here is a string that contains inline arguments for jar.
            pb.redirectErrorStream(true);
            pb.directory(new File("C:\\Users\\Dharma"));

            System.out.println("Directory: " + pb.directory().getAbsolutePath());
            Process p = pb.start();
            InputStream is = p.getInputStream();
            BufferedReader br = new BufferedReader(new InputStreamReader(is));
            for (String line = br.readLine(); line != null; line = br.readLine()) {
                    System.out.println( line ); 
            p.waitFor();

以上兩個都不適合我。 任何建議表示贊賞。

Answer 1

這對我有用..

public class JarRunner {
    public static void main(String[] args) {
        ProcessBuilder pb = new ProcessBuilder("java", "-jar", "C:\\JCcc.jar");
        pb.directory(new File("C:\\"));
        try {
            Process p = pb.start();
            LogStreamReader lsr = new LogStreamReader(p.getInputStream());
            Thread thread = new Thread(lsr, "LogStreamReader");
            thread.start();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

class LogStreamReader implements Runnable {

    private BufferedReader reader;

    public LogStreamReader(InputStream is) {
        this.reader = new BufferedReader(new InputStreamReader(is));
    }

    public void run() {
        try {
            String line = reader.readLine();
            while (line != null) {
                System.out.println(line);
                line = reader.readLine();
            }
            reader.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

這就是Docs所說的 -

ProcessBuilder pb = new ProcessBuilder("myCommand", "myArg1", "myArg2");

您可以在構造函數中傳遞任意數量的參數。

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