package commands;

import java.io.*;
import java.util.List;

import kernel.*;

/**
 * Prints all running processes.
 * 
 * @author Tomáš Podskalský
 */
public class ps extends AbstractProcess {
  public void realization() throws AppException {
    PipedOutputStream output = (this.getOut() != null) ? (PipedOutputStream) this
        .getOut()
        : null;
    List<AbstractProcess> processes = getServices().getProcesses();
    try {
      for (AbstractProcess process : processes)
        if (process.getID() != this.getID()) {
          String s = new String("[" + process.getID() + "] "
              + process.getCommand() + "\n");
          output.write(s.getBytes());
          output.flush();
        }
      String s = new String("[" + this.getID() + "] " + this.getCommand()
          + "\n");
      output.write(s.getBytes());
      output.flush();
    } catch (IOException ioe) {
      ioe.printStackTrace();
      throw new AppException("Chyba I/O\n" + ioe.getMessage(), ioe);
    } catch (NullPointerException npe) {
      npe.printStackTrace();
      throw new AppException("Output není definován\n" + npe.getMessage(), npe);
    } catch (Exception e) {
      e.printStackTrace();
      throw new AppException("Neznámá Chyba.\n" + e.getMessage(), e);
    }
  }

  /**
   * Provides help for users.
   * 
   */

  public String getHelp() {
    return "\n\nDescription:\nPrints all running processes.\n\n";
  }
}