Java-Buddy

This example show a how to use PrintWriter to print to System.out and file. PrintWriter prints formatted representations of objects to a text-output stream. We will use last example of "ProcessBuilder to create operating system processes" to get input from.

package java_processbuilder;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
 *
 * @web java-buddy.blogspot.com
 */
public class Java_ProcessBuilder {
 public static void main(String[] args) {
 // Example to run "dir" in Windows
 String[] command = {"cmd", "/c", "dir"};
 StringBuilder cmdReturn = new StringBuilder();
 try {
 //print to System.out
 PrintWriter printWriter_out = new PrintWriter(System.out, true);
 
 //print to file, text.txt
 File file = new File("test.txt");
 file.createNewFile();
 try (PrintWriter printWriter_file = new PrintWriter(new FileWriter(file))) {
 ProcessBuilder processBuilder = new ProcessBuilder(command);
 Process process = processBuilder.start();
 
 try (InputStream inputStream = process.getInputStream()) {
 int c;
 while ((c = inputStream.read()) != -1) {
 cmdReturn.append((char) c);
 }
 }
 
 //System.out.println(cmdReturn.toString());
 printWriter_out.println(cmdReturn.toString());
 printWriter_file.println(cmdReturn.toString());
 }
 } catch (IOException ex) {
 Logger.getLogger(Java_ProcessBuilder.class.getName())
 .log(Level.SEVERE, null, ex);
 }
 }
}

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