Java tutorial
/* * JBoss, Home of Professional Open Source * Copyright 2010, Red Hat Middleware LLC, and individual contributors * by the @authors tag. See the copyright.txt in the distribution for a * full listing of individual contributors. * * 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 com.acme.jpa; import java.io.Serializable; import java.math.BigDecimal; import java.util.Collections; import java.util.HashSet; import java.util.Set; import javax.persistence.CascadeType; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.Id; import javax.persistence.ManyToMany; import javax.persistence.Column; import javax.validation.constraints.Min; import javax.validation.constraints.NotNull; import javax.validation.constraints.Size; import org.apache.commons.lang.builder.EqualsBuilder; import org.apache.commons.lang.builder.HashCodeBuilder; @Entity public class Game implements Serializable { private static final long serialVersionUID = 2794223977275773955L; @Id @GeneratedValue private Long id; @NotNull @Size(min = 3, max = 50) private String title; @NotNull private BigDecimal price; @NotNull @Min(1960) @Column(name = "YEAR_RELEASED") private Integer year; @ManyToMany(cascade = { CascadeType.PERSIST, CascadeType.MERGE }) private Set<Platform> supportedPlatforms = new HashSet<Platform>(); Game() { // To satisfy JPA } public Game(String title, Integer year, BigDecimal price) { this.title = title; this.year = year; this.price = price; } public void addPlatform(Platform platform) { if (supportedPlatforms.contains(platform)) { return; } supportedPlatforms.add(platform); platform.addGames(this); } @Override public boolean equals(Object obj) { if (this == obj) { return true; } if (!(obj instanceof Game)) { return false; } final Game other = (Game) obj; return new EqualsBuilder().append(title, other.getTitle()).append(year, other.getYear()).isEquals(); } @Override public int hashCode() { return new HashCodeBuilder(11, 17).append(title).append(year).toHashCode(); } public String toString() { return "Game@" + hashCode() + "[id = " + id + "; title = " + title + "; price = " + price + "]"; } // Accessors public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getTitle() { return title; } public void setTitle(String name) { this.title = name; } public BigDecimal getPrice() { return price; } public void setPrice(BigDecimal price) { this.price = price; } public Integer getYear() { return year; } public void setYear(Integer year) { this.year = year; } public Set<Platform> getSupportedPlatforms() { return Collections.unmodifiableSet(supportedPlatforms); } public void setSupportedPlatforms(Set<Platform> supportedPlatforms) { this.supportedPlatforms = supportedPlatforms; } }