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java運行shell腳本方法示例

 利用Runtime.execute方法,我們可以在Java程序中運行Linux的Shell腳本,或者執行其他程序

  現在通過CommandHelper.execute方法可以執行命令,該類實現   代碼如下: 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類使用了CommandResult對象輸出結果錯誤信息。該類實現      代碼如下: 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;     } }       現在看看調用代碼的演示(main函數接受一個超時參數):   代碼如下: 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());         }     }     結果會創建一個testdir目錄。 我嘗試用這種方法創建通過ssh登錄到遠程機器,遇到兩個問題: 1)如果希望沒有人機對話方式,則需要使用命令sshpass -p password ssh user@targetIP 'command' 2) 在NetBeans上直接運行工程是不行的,因為權限不夠,需要在終端裡運行java javaapplication3.Main 3) 很多命令不能運行,只有如pwd等命令可以運行,原因還不清楚,最好改用Ganymed SSH-2庫或者其他類似Java庫,我會在下一篇文章中介紹如何使用。  
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