net.viktorc.pp4j.impl.SimpleProcessManager Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of pp4j Show documentation
A multiprocessing library for Java.
There is a newer version: 3.0.2
/*
 * Copyright 2017 Viktor Csomor
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package net.viktorc.pp4j.impl;

import java.util.function.Consumer;

import net.viktorc.pp4j.api.ProcessExecutor;

/**
 * A simplified sub-class of the {@link net.viktorc.pp4j.impl.AbstractProcessManager} abstract class. It assumes 
 * that the process is immediately started up as soon as it is running (without having to wait for a certain output 
 * denoting that the process is ready), it has the process forcibly killed every time it needs to be terminated due 
 * to exceeding the keep-alive-time of the pool or not being reusable, and it implements no callback for when the 
 * process terminates.
 * 
 * @author Viktor Csomor
 *
 */
public class SimpleProcessManager extends AbstractProcessManager {

	private final Consumer onStartup;
	
	/**
	 * Constructs a manager for the processes created by the specified {@link java.lang.ProcessBuilder} with the 
	 * specified maximum life span.
	 * 
	 * @param builder The instance to build the processes with.
	 * @param keepAliveTime The number of milliseconds after which idle processes are terminated. If it is 
	 * 0 or less, the life span of the process will not be limited.
	 * @param onStartup A consumer that is called after the process started up to allow for the execution 
	 * of commands to 'prepare' the process for the pool. If it is null, no preprocessing is performed.
	 */
	public SimpleProcessManager(ProcessBuilder builder, long keepAliveTime,
			Consumer onStartup) {
		super(builder, keepAliveTime);
		this.onStartup = onStartup;
	}
	/**
	 * Constructs a manager for the processes created by the specified {@link java.lang.ProcessBuilder} with the 
	 * specified maximum life span.
	 * 
	 * @param builder The instance to build the processes with.
	 * @param keepAliveTime The number of milliseconds after which idle processes are terminated. If it is 
	 * 0 or less, the life span of the process will not be limited.
	 */
	public SimpleProcessManager(ProcessBuilder builder, long keepAliveTime) {
		this(builder, keepAliveTime, null);
	}
	/**
	 * Constructs a manager for the processes created by the specified {@link java.lang.ProcessBuilder}.
	 * 
	 * @param builder The instance to build the processes with.
	 * @param onStartup A consumer that is called after the process started up to allow for the execution 
	 * of commands to 'prepare' the process for the pool.
	 */
	public SimpleProcessManager(ProcessBuilder builder, Consumer onStartup) {
		this(builder, 0, onStartup);
	}
	/**
	 * Constructs a manager for the processes created by the specified {@link java.lang.ProcessBuilder}.
	 * 
	 * @param builder The instance to build the processes with.
	 */
	public SimpleProcessManager(ProcessBuilder builder) {
		this(builder, 0);
	}
	@Override
	public boolean startsUpInstantly() {
		return true;
	}
	@Override
	public boolean isStartedUp(String outputLine, boolean standard) {
		return true;
	}
	@Override
	public void onStartup(ProcessExecutor executor) {
		if (onStartup != null)
			onStartup.accept(executor);
		else
			super.onStartup(executor);
	}

}