(java)

process-test.java

process-test.java

package com.metasoft.util;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;

public class ProcessUtil {
	public static void Shell(String cmd) throws Exception {
		cmd = cmd == null ? "/bin/sh" : cmd;
		ProcessBuilder processBuilder = new ProcessBuilder(cmd); 
		Process process = processBuilder.start();
		
		//Output to the stream is piped into the standard input of the process represented by this Process object
		OutputStream stdin = process.getOutputStream(); // <- Eh?
		//the standard output of a subprocess can be read using the input stream 
        InputStream stdout = process.getInputStream();

        BufferedReader reader = new BufferedReader(new InputStreamReader(stdout));
        BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(stdin));
        
        new Thread(new Runnable() {
            public void run() { 
               try {
                  while (true) {
                	  String line = reader.readLine();
                	  if(line!=null)
                		  System.out.println(line);
                  }
               } catch (Exception ex) {
                  ex.printStackTrace(); 
               }

            }
         }).start();
        
        for(int i=0;i<10;i++){  
        	writer.write("echo 'bar'");
        	writer.newLine();
            writer.flush();
        }
        /*writer.write("val textFile = spark.read.textFile(\"README.md\")");
        writer.newLine();
        writer.write("textFile.count()");
        writer.newLine();
        writer.write("textFile.first() ");
        writer.newLine();
        writer.write("textFile.filter(line => line.contains(\"Spark\")).count()");
        writer.newLine();
        writer.flush(); */
        
        writer.close();
        
        //process.waitFor(); 
	   }

	/*
	 * new ProcessBuilder("/bin/sh", "-c", "echo 'foo'>bar");
	 * 
	 * public static void Shell_() throws Exception { ProcessBuilder pb = new
	 * ProcessBuilder("/bin/sh", "-c", "echo $VAR1"); Map<String, String> env =
	 * pb.environment(); env.put("VAR1", "myValue"); env.remove("OTHERVAR");
	 * env.put("VAR2", env.get("VAR1") + "suffix"); pb.directory(new File("."));
	 * File log = new File("log"); pb.redirectErrorStream(true);
	 * pb.redirectOutput(Redirect.appendTo(log)); Process p = pb.start(); assert
	 * pb.redirectInput() == Redirect.PIPE; assert pb.redirectOutput().file() ==
	 * log; assert p.getInputStream().read() == -1; }
	 */
		public static void main(String[] args) throws Exception {
			Shell(args[0]);
		}

}