EJB Tutorial from JBoss: single inheritance
File: Cat.java /* * JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jboss.tutorial.singleinheritance.bean; import javax.persistence.DiscriminatorType; import javax.persistence.Entity; import javax.persistence.Inheritance; import javax.persistence.InheritanceType; import javax.persistence.DiscriminatorColumn; import javax.persistence.DiscriminatorValue; @Entity @Inheritance(strategy = InheritanceType.SINGLE_TABLE) @DiscriminatorColumn(discriminatorType = DiscriminatorType.STRING) @DiscriminatorValue("CAT") public class Cat extends Pet { public String getHairball() { return hairball; } public void setHairball(String hairball) { this.hairball = hairball; } String hairball; } File: Dog.java /* * JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jboss.tutorial.singleinheritance.bean; import javax.persistence.DiscriminatorType; import javax.persistence.Entity; import javax.persistence.Inheritance; import javax.persistence.InheritanceType; import javax.persistence.DiscriminatorColumn; import javax.persistence.DiscriminatorValue; @Entity @Inheritance(strategy = InheritanceType.SINGLE_TABLE) @DiscriminatorColumn(discriminatorType = DiscriminatorType.STRING) @DiscriminatorValue("DOG") public class Dog extends Pet { private String trick; public String getTrick() { return trick; } public void setTrick(String trick) { this.trick = trick; } } File: Pet.java /* * JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jboss.tutorial.singleinheritance.bean; import javax.persistence.DiscriminatorColumn; import javax.persistence.DiscriminatorType; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.GenerationType; import javax.persistence.Id; import javax.persistence.Inheritance; import javax.persistence.InheritanceType; @Entity @Inheritance(strategy = InheritanceType.SINGLE_TABLE) @DiscriminatorColumn(name = "ANIMAL_TYPE", discriminatorType = DiscriminatorType.STRING) public class Pet implements java.io.Serializable { private int id; private String name; private double weight; @Id @GeneratedValue(strategy=GenerationType.AUTO) public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public double getWeight() { return weight; } public void setWeight(double weight) { this.weight = weight; } } File: PetDAO.java /* * JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jboss.tutorial.singleinheritance.bean; import java.util.List; public interface PetDAO { void createDog(String name, double weight, int bones); void createCat(String name, double weight, int lives); List findByWeight(double weight); } File: PetDAOBean.java /* * JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jboss.tutorial.singleinheritance.bean; import java.util.List; import javax.ejb.Remote; import javax.ejb.Stateless; import javax.persistence.EntityManager; import javax.persistence.PersistenceContext; @Stateless @Remote(PetDAO.class) public class PetDAOBean implements PetDAO { @PersistenceContext private EntityManager manager; public void createDog(String name, double weight, int bones) { Dog dog = new Dog(); dog.setName(name); dog.setWeight(weight); dog.setTrick("Sit"); manager.persist(dog); } public void createCat(String name, double weight, int lives) { Cat cat = new Cat(); cat.setName(name); cat.setWeight(weight); cat.setHairball("#$@#%@"); manager.persist(cat); } public List findByWeight(double weight) { return manager.createQuery("select p from Pet p where p.weight < :weight").setParameter("weight", weight).getResultList(); } } File: Client.java /* * JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jboss.tutorial.singleinheritance.Client; import org.jboss.tutorial.singleinheritance.bean.Pet; import org.jboss.tutorial.singleinheritance.bean.PetDAO; import javax.naming.InitialContext; import java.util.List; /** * Comment * * @author <a href="mailto:bill@jboss.org">Bill Burke</a> * @version $Revision: 57207 $ */ public class Client { public static void main(String[] args) throws Exception { InitialContext ctx = new InitialContext(); PetDAO dao = (PetDAO) ctx.lookup("PetDAOBean/remote"); dao.createCat("Toonses", 15.0, 9); dao.createCat("Sox", 10.0, 5); dao.createDog("Winnie", 70.0, 5); dao.createDog("Junior", 11.0, 1); List l = dao.findByWeight(14.0); for (Object o : l) { System.out.println(((Pet) o).getName()); } } }
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