java执行执行shell java执行shell文件

利用Runtime.execute方法，我们可以在Java程序中运行Linux的Shell脚本，或者执行其他程序。参考了互联网上的这篇文章：http://lee79.javaeye.com/blog/418549（感谢一下），我重新整理了代码。
现在通过CommandHelper.execute方法可以执行命令，该类实现代码如下：

package javaapplication3;


 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStreamReader;

 /**
  *
  * @author chenshu
  */
 public class CommandHelper {

     //default time out, in millseconds
     public static int DEFAULT_TIMEOUT;
     public static final int DEFAULT_INTERVAL = 1000;
     public static long START;


     public static CommandResult exec(String command) throws IOException, InterruptedException {
         Process process = Runtime.getRuntime().exec(command);
         CommandResult commandResult = wait(process);
         if (process != null) {
             process.destroy();
         }
         return commandResult;
     }

     private static boolean isOverTime() {
         return System.currentTimeMillis() - START >= DEFAULT_TIMEOUT;
     }

     private static CommandResult wait(Process process) throws InterruptedException, IOException {
         BufferedReader errorStreamReader = null;
         BufferedReader inputStreamReader = null;
         try {
             errorStreamReader = new BufferedReader(new InputStreamReader(process.getErrorStream()));
             inputStreamReader = new BufferedReader(new InputStreamReader(process.getInputStream()));

             //timeout control
             START = System.currentTimeMillis();
             boolean isFinished = false;

             for (;;) {
                 if (isOverTime()) {
                     CommandResult result = new CommandResult();
                     result.setExitValue(CommandResult.EXIT_VALUE_TIMEOUT);
                     result.setOutput("Command process timeout");
                     return result;
                 }

                 if (isFinished) {
                     CommandResult result = new CommandResult();
                     result.setExitValue(process.waitFor());
                     
                     //parse error info
                     if (errorStreamReader.ready()) {
                         StringBuilder buffer = new StringBuilder();
                         String line;
                         while ((line = errorStreamReader.readLine()) != null) {
                             buffer.append(line);
                         }
                         result.setError(buffer.toString());
                     }

                     //parse info
                     if (inputStreamReader.ready()) {
                         StringBuilder buffer = new StringBuilder();
                         String line;
                         while ((line = inputStreamReader.readLine()) != null) {
                             buffer.append(line);
                         }
                         result.setOutput(buffer.toString());
                     }
                     return result;
                 }

                 try {
                     isFinished = true;
                     process.exitValue();
                 } catch (IllegalThreadStateException e) {
                     // process hasn't finished yet
                     isFinished = false;
                     Thread.sleep(DEFAULT_INTERVAL);
                 }
             }

         } finally {
             if (errorStreamReader != null) {
                 try {
                     errorStreamReader.close();
                 } catch (IOException e) {
                 }
             }

             if (inputStreamReader != null) {
                 try {
                     inputStreamReader.close();
                 } catch (IOException e) {
                 }
             }
         }
     }
 }

CommandHelper类使用了CommandResult对象输出结果错误信息。该类实现代码如下：

package javaapplication3;
 /**
  *
  * @author chenshu
  */
 public class CommandResult {
     public static final int EXIT_VALUE_TIMEOUT=-1;
     
     private String output;

     void setOutput(String error) {
         output=error;
     }

     String getOutput(){
         return output;
     }

     int exitValue;

     void setExitValue(int value) {
         exitValue=value;
     }

     int getExitValue(){
         return exitValue;
     }

     private String error;

     /**
      * @return the error
      */
     public String getError() {
         return error;
     }

     /**
      * @param error the error to set
      */
     public void setError(String error) {
         this.error = error;
     }
 }

现在看看调用代码的演示（main函数接受一个超时参数）：

public static void main(String[] args) {
         try {
             int timeout = Integer.parseInt(args[0]);
             CommandHelper.DEFAULT_TIMEOUT = timeout;
             CommandResult result = CommandHelper.exec("mkdir testdir");
             if (result != null) {
                 System.out.println("Output:" + result.getOutput());
                 System.out.println("Error:" + result.getError());
             }
         } catch (IOException ex) {
             System.out.println("IOException:" + ex.getLocalizedMessage());
         } catch (InterruptedException ex) {
             System.out.println("InterruptedException:" + ex.getLocalizedMessage());
         }
     }

结果会创建一个testdir目录。

我尝试用这种方法创建通过ssh登录到远程机器，遇到两个问题：
1）如果希望没有人机对话方式，则需要使用命令sshpass -p password ssh user@targetIP 'command'
2) 在NetBeans上直接运行工程是不行的，因为权限不够,需要在终端里运行java javaapplication3.Main
3) 很多命令不能运行，只有如pwd等命令可以运行，原因还不清楚，最好改用Ganymed SSH-2库或者其他类似Java库，我会在下一篇文章中介绍如何使用。