ExecDemo shows how to execute an external program and read its output
/*
* Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002.
* All rights reserved. Software written by Ian F. Darwin and others.
* $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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*
* Java, the Duke mascot, and all variants of Sun's Java "steaming coffee
* cup" logo are trademarks of Sun Microsystems. Sun's, and James Gosling's,
* pioneering role in inventing and promulgating (and standardizing) the Java
* language and environment is gratefully acknowledged.
*
* The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
* inventing predecessor languages C and C++ is also gratefully acknowledged.
*/
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
/**
* ExecDemo shows how to execute an external program and read its output.
*/
public class ExecDemoSort {
public static void main(String[] av) throws IOException {
// A Runtime object has methods for dealing with the OS
Runtime r = Runtime.getRuntime();
// A process object tracks one external running process
Process p;
// file contains unsorted data
p = r.exec("sort sortdemo.txt");
// getInputStream gives an Input stream connected to
// the process p's standard output (and vice versa). We use
// that to construct a BufferedReader so we can readLine() it.
BufferedReader is = new BufferedReader(new InputStreamReader(p
.getInputStream()));
System.out.println("Here is your sorted data:");
String aLine;
while ((aLine = is.readLine()) != null)
System.out.println(aLine);
System.out.println("That is all, folks!");
return;
}
}
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