Java 如何使用运行时？

我想用java使用下面给出的commnda。我使用了RunTime。但在运行时，结果是所有时间都为空

$ cut -d. -f2,3 <<< com.tata.titi.toto
tata.titi

---

$cut-d-f2,3删除
进程waitFor（）。您正在运行进程，等待其终止，然后在太晚时尝试读取其输出

如果删除该行，则执行该进程并读取其输出。我希望这对你有帮助

顺便说一句，你为什么要这样做？您可以逐行读取文件，并在java中拆分每一行。这更简单，跨平台。
但是在单独的线程中处理错误流为什么？请参阅javadoc

因为某些本机平台仅为提供有限的缓冲区大小
标准输入和输出流，未能及时写入输入
流或读取子流程的输出流可能会导致
子进程阻塞，甚至死锁

这就是你可以使用它的方式

        Process proc = procBldr.start();
        //props is a java.util.properties that was previosly loaded from some stream
        System.out.println(" Cmd start f :" + cmdStartFolder);
        System.out.println(" Cmd  :" + lstCmds);
        BufferedReader isO = new BufferedReader (new InputStreamReader(proc.getInputStream()));
        BufferedReader isE = new BufferedReader (new InputStreamReader(proc.getErrorStream()));
        asynO = new com.enstage.commonutil.file.ReadStreamAsync(isO, 1, true);
        asynE = new com.enstage.commonutil.file.ReadStreamAsync(isE, 1, true);
        if("1".equals(props.getProperty("waitFor")){
            proc.waitFor();//maybe parameterize this not required everywhere only good for short processes 
        }
        String sleepAfterWait = props.getProperty("sleepAfterWait");
        try {
            Thread.sleep(500);//some sleep after telling windows to do things with files is good
            if(sleepAfterWait != null){
                int i = Integer.parseInt(sleepAfterWait);
                Thread.sleep(i);
            }
        } catch (Exception e) {
            System.out.println("sleep err :" + e );
            e.printStackTrace();
        }
        asynE.join();
        asynO.join();
        String checkString = props.getProperty("checkString");
        System.out.println("\n done " );
        //asynE.getRead();//if you want error out as a string
        if(checkString != null){
            System.out.println("checkString :" + checkString );
            String out = asynO.getRead();
            if(out.indexOf(checkString) > -1){
                System.out.println(" Check string found!" );
            }else{
                System.err.println(" *** Check string not found ***!" );
            }
        }

如果成功地使用它调用.bat中的xcopy和其他短流程和长流程
过一段时间，我将拥有path/com.tata.titi.toto。我不知道使用拆分是否更容易。事实上，我有一个包含许多应用程序的文件夹，命名为com.tata.titi.toto.apk，应用程序的名称是tata.titi。我希望有一个映射，这不是等待的问题，我使用了一些synthese和process。等待一个，它是好的，当我更改命令时，我得到了我想要的。但我会使用带有输入和错误字符串的版本，只需在单独的线程上等待错误，这样一个进程就可以发送很少的输出，然后是错误，然后是更多的输出。。。。
package utl;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileReader;    

public class ReadStreamAsync extends Thread {

    private BufferedReader is = null;
    private int toOut = 0;//0 none, 1 out, 2 err
    private boolean toSB = false;
    private StringBuffer sb = null;
    public ReadStreamAsync(BufferedReader is, int toOut, boolean toSB){
        if(is == null)throw new NullPointerException("stream is null");
        this.is = is;
        this.toSB = toSB;
        this.toOut = toOut;
        if(toSB)sb = new StringBuffer();
        start();
    }

    public void run(){
        try{
            int i;
            while((i = is.read()) > -1){
                if(toOut == 1){
                    System.out.print((char)i);
                }else if(toOut ==2){
                    System.err.print((char)i);
                }
                if(toSB)sb.append((char)i);
            }
        }catch(Exception e){
            e.printStackTrace();
        }finally{
                    try{
                            is.close();
                    }catch(Exception e){
                            e.printStackTrace();
                    }
                }
    }

    public String getRead(){
        return sb.toString();
    }

    /**
         * test code
     * @param args
     */
    public static void main(String[] args) {
        try{
            BufferedReader fis = new BufferedReader(new FileReader("c:/tmp/sample1.txt"));
            ReadStreamAsync t = new ReadStreamAsync(fis, 1, false);
            t.join(1000);
            System.out.println("\nAll :");
            fis = new BufferedReader(new FileReader("c:/tmp/sample1.txt"));
             t = new ReadStreamAsync(fis, 0, true);
            t.join(1000);
            System.out.println(t.getRead());

        }catch(Exception e){
            e.printStackTrace();
        }

    }

}

        Process proc = procBldr.start();
        //props is a java.util.properties that was previosly loaded from some stream
        System.out.println(" Cmd start f :" + cmdStartFolder);
        System.out.println(" Cmd  :" + lstCmds);
        BufferedReader isO = new BufferedReader (new InputStreamReader(proc.getInputStream()));
        BufferedReader isE = new BufferedReader (new InputStreamReader(proc.getErrorStream()));
        asynO = new com.enstage.commonutil.file.ReadStreamAsync(isO, 1, true);
        asynE = new com.enstage.commonutil.file.ReadStreamAsync(isE, 1, true);
        if("1".equals(props.getProperty("waitFor")){
            proc.waitFor();//maybe parameterize this not required everywhere only good for short processes 
        }
        String sleepAfterWait = props.getProperty("sleepAfterWait");
        try {
            Thread.sleep(500);//some sleep after telling windows to do things with files is good
            if(sleepAfterWait != null){
                int i = Integer.parseInt(sleepAfterWait);
                Thread.sleep(i);
            }
        } catch (Exception e) {
            System.out.println("sleep err :" + e );
            e.printStackTrace();
        }
        asynE.join();
        asynO.join();
        String checkString = props.getProperty("checkString");
        System.out.println("\n done " );
        //asynE.getRead();//if you want error out as a string
        if(checkString != null){
            System.out.println("checkString :" + checkString );
            String out = asynO.getRead();
            if(out.indexOf(checkString) > -1){
                System.out.println(" Check string found!" );
            }else{
                System.err.println(" *** Check string not found ***!" );
            }
        }