ControlableProcess.java

/* 
 * Copyright (C) 2014 Mark Clarke
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package za.co.jumpingbean.gc.service;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.List;
import java.util.Scanner;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author Mark Clarke
 */
public class ControlableProcess extends ProcessObject {

    private final ProcessParams params;
    private final Process process;
    private final ProcOutputReaderList procOutputReader;
    private BufferedReader reader;
    
    
    public ControlableProcess(String name,Process proc, ProcessParams params,
            ProcOutputReaderList output, JMXQueryRunner qry) {
        super(name,qry);
        this.process = proc;
        this.params = params;
        procOutputReader = output;
        if (!params.getLogFilename().isEmpty()){
            try {
                reader = new BufferedReader(new FileReader(new File(params.getLogFilename())));
            } catch (FileNotFoundException ex) {
                reader=null;
                System.out.println("log file not found");
            }
        }
    }

    public ProcessParams getParams() {
        return params;
    }
    
    public Process getProcess() {
        return process;
    }
    
    String getGCLogEntries(){
        if (reader!=null){
            try {
                StringBuilder line=new StringBuilder();
                String l = reader.readLine();
                while(l!=null){
                    line.append(String.format("%s%n",l));
                    l = reader.readLine();
                }
                return line.toString();
            } catch (IOException ex) {
                System.out.println("Error reading line from log file");
                return "";
            }
        }
        return readProcessOutputLine();
    }
    
    String readProcessOutputLine() {
        List<String> list = procOutputReader.readList();
        if (list.isEmpty()){
            return "";
        }
        StringBuilder str = new StringBuilder(200);
        for (String tmpStr : list) {
            str.append(String.format("%s%n",tmpStr));
        }
        return str.toString();
    }

    public void stop() {
        this.procOutputReader.stop();
        this.process.destroy();
        try {
            synchronized (process) {
                process.wait(500L);
                process.exitValue();
            }
        } catch (InterruptedException ex) {
            Logger.getLogger(GeneratorService.class.getName()).log(Level.SEVERE, null, ex);
        } catch (IllegalThreadStateException ex) {
            throw new IllegalStateException("failed to stop process" + process.toString());
        }            
    }

}