parent.java

hibernate方便的操作数据库相当不错的 请各位下载看看啊

//$Id: Parent.java,v 1.3 2005/02/13 22:46:18 epbernard Exp $
package org.hibernate.test.metadata.onetomany;

import org.hibernate.annotations.BatchSize;

import javax.ejb.Entity;
import javax.ejb.AccessType;
import javax.ejb.Id;
import javax.ejb.OneToMany;
import javax.ejb.CascadeType;
import javax.ejb.JoinColumns;
import javax.ejb.JoinColumn;
import java.util.Collection;
import java.util.Set;
import java.util.HashSet;
import java.io.Serializable;

/**
 * @author Emmanuel Bernard
 */
@Entity(access = AccessType.FIELD)
public class Parent implements Serializable {
	@Id
	public ParentPk id;
	public int age;
	
	@OneToMany(cascade=CascadeType.ALL)
	@JoinColumns ({
		@JoinColumn(name="parentCivility", referencedColumnName = "isMale"),
		@JoinColumn(name="parentLastName", referencedColumnName = "lastName"),
		@JoinColumn(name="parentFirstName", referencedColumnName = "firstName")
	})
	@BatchSize(size=5)
	public Set<Child> children;

	public int hashCode() {
		//a NPE can occurs, but I don't expect hashcode to be used before pk is set
		return id.hashCode();
	}

	public boolean equals(Object obj) {
		//a NPE can occurs, but I don't expect equals to be used before pk is set
		if (obj != null && obj instanceof Parent) {
			return id.equals( ( (Parent) obj).id );
		}
		else {
			return false;
		}
	}

	public void addChild(Child child) {
		if (children == null) {
			children = new HashSet();
		}
		child.parent = this;
		children.add(child);
	}
}