com.darwinsys.lang.ExecAndPrint Maven / Gradle / Ivy
package com.darwinsys.lang;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.Writer;
import com.darwinsys.io.FileIO;
/**
* ExecAndPrint runs a program using Runtime.exec(),
* read the program's output, and returns its exit status.
*/
public class ExecAndPrint {
// BEGIN main
/** Need a Runtime object for any of these methods */
protected final static Runtime r = Runtime.getRuntime();
/** Run the command given as a String, output to System.out
* @param cmd The command
* @return The command's exit status
* @throws IOException if the command isn't found
*/
public static int run(String cmd) throws IOException {
return run(cmd, new OutputStreamWriter(System.out));
}
/** Run the command given as a String, output to "out"
* @param cmd The command and list of arguments
* @param out The output file
* @return The command's exit status
* @throws IOException if the command isn't found
*/
public static int run(String cmd, Writer out) throws IOException {
Process p = r.exec(cmd);
FileIO.copyFile(new InputStreamReader(p.getInputStream()), out, true);
try {
p.waitFor(); // wait for process to complete
} catch (InterruptedException e) {
return -1;
}
return p.exitValue();
}
// END main
/** Run the command given as a String[], output to System.out
* @param cmd The command and list of arguments
* @return The command's exit status
* @throws IOException if the command isn't found
*/
public static int run(String[] cmd) throws IOException {
return run(cmd, new OutputStreamWriter(System.out));
}
/** Run the command given as a String[], print its output to "out"
* @param cmd The command and list of arguments
* @param out The output file
* @return The command's exit status
* @throws IOException if the command isn't found
*/
public static int run(String[] cmd, Writer out) throws IOException {
Process p = r.exec(cmd);
FileIO.copyFile(new InputStreamReader(p.getInputStream()), out, true);
try {
p.waitFor(); // wait for process to complete
} catch (InterruptedException e) {
return -1;
}
return p.exitValue();
}
}