的Java：從Java

Question

運行一個批處理腳本，當我需要從Java執行批處理腳本，一旦啓動它執行一個漫長的（幾秒鐘）的任務，並以下

1）檢測用戶提示。

2）此後，它顯示提示「密碼：」。

3）然後，用戶輸入密碼並按Enter鍵。

4）然後，腳本完成它的工作。我知道如何從Java中啓動腳本，我知道如何閱讀Java中批處理腳本的輸出，但我不知道如何等待密碼提示出現（我如何知道批處理腳本正在等待密碼輸入）。

所以，我的問題是：如何知道批處理腳本何時打印提示？

此刻，我有以下代碼：

final Runtime runtime = Runtime.getRuntime(); 
final String command = ... ; 

final Process proc = runtime.exec(command, null, this.parentDirectory); 

final BufferedReader input = new BufferedReader(new InputStreamReader(
    proc.getInputStream())); 

String line = null; 

while ((line = input.readLine()) != null) { 
LOGGER.debug("proc: " + line); 
} 

Answer 1

這應該做的工作：

public static void main(final String... args) throws IOException, InterruptedException { 
    final Runtime runtime = Runtime.getRuntime(); 
    final String command = "..."; // cmd.exe 

    final Process proc = runtime.exec(command, null, new File(".")); 

    final BufferedReader input = new BufferedReader(new InputStreamReader(proc.getInputStream())); 

    StringBuilder sb = new StringBuilder(); 
    char[] cbuf = new char[100]; 
    while (input.read(cbuf) != -1) { 
     sb.append(cbuf); 
     if (sb.toString().contains("Password:")) { 
      break; 
     } 
     Thread.sleep(1000); 
    } 
    System.out.println(sb); 
} 

Answer 2

這一個似乎工作：

@Override 
public void run() throws IOException, InterruptedException { 
    final Runtime runtime = Runtime.getRuntime(); 
    final String command = ...; 

    final Process proc = runtime.exec(command, null, this.parentDirectory); 

    final BufferedReader input = new BufferedReader(new InputStreamReader(
      proc.getInputStream())); 

    String batchFileOutput = ""; 

    while (input.ready()) { 
     char character = (char) input.read(); 
     batchFileOutput = batchFileOutput + character; 
    } 

    // Batch script has printed the banner 
    // Wait for the password prompt 
    while (!input.ready()) { 
     Thread.sleep(1000); 
    } 

    // The password prompt isn't terminated by a newline - that's why we can't use readLine. 
    // Instead, we need to read the stuff character by character. 
    batchFileOutput = ""; 

    while (input.ready() && (!batchFileOutput.endsWith("Password: "))) { 
     char character = (char) input.read(); 
     batchFileOutput = batchFileOutput + character; 
    } 

    // When we are here, the prompt has been printed 
    // It's time to enter the password 

    if (batchFileOutput.endsWith("Password: ")) { 
     final BufferedWriter writer = new BufferedWriter(
       new OutputStreamWriter(proc.getOutputStream())); 

     writer.write(this.password); 

     // Simulate pressing of the Enter key 
     writer.newLine(); 

     // Flush the stream, otherwise it doesn't work 
     writer.flush(); 
    } 

    // Now print out the output of the batch script AFTER we have provided it with a password 
    String line; 

    while ((line = input.readLine()) != null) { 
     LOGGER.debug("proc: " + line); 
    } 

    // Print out the stuff on stderr, if the batch script has written something into it 
    final BufferedReader error = new BufferedReader(new InputStreamReader(
      proc.getErrorStream())); 

    String errorLine = null; 

    while ((errorLine = error.readLine()) != null) { 
     LOGGER.debug("proc2: " + errorLine); 
    } 

    // Wait until the program has completed 

    final int result = proc.waitFor(); 

    // Log the result 
    LOGGER.debug("result: " + result); 
}