Hibernate 使用 Annotation 3（联合主键）

Hibernate Annotation 联合主键有三种写法 ：

第一种：

Jlee01.java代码：

package com.jlee03.compositeId;

import java.io.Serializable;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;

/**
 * @author JLee
 * @since 2011-2-10
 */
@Entity
@Table(name="JLEE01")
public class Jlee01 implements Serializable{

	private static final long serialVersionUID = 3524215936351012384L;
	private String address ;
	private int age ;
	private String email ;
	private String phone ;
	private JleeKey01 jleeKey ;
	
	/**
	 * @return the jleeKey
	 */
	@Id
	public JleeKey01 getJleeKey() {
		return jleeKey;
	}
	/**
	 * @param jleeKey the jleeKey to set
	 */
	public void setJleeKey(JleeKey01 jleeKey) {
		this.jleeKey = jleeKey;
	}
	/**
	 * @return the phone
	 */
	@Column(name="phone" , length=20)
	public String getPhone() {
		return phone;
	}
	/**
	 * @param phone the phone to set
	 */
	public void setPhone(String phone) {
		this.phone = phone;
	}
	/**
	 * @return the address
	 */
	@Column(name="address" , length=50)
	public String getAddress() {
		return address;
	}
	/**
	 * @param address the address to set
	 */
	public void setAddress(String address) {
		this.address = address;
	}
	/**
	 * @return the age
	 */
	@Column(name="age")
	public int getAge() {
		return age;
	}
	/**
	 * @param age the age to set
	 */
	public void setAge(int age) {
		this.age = age;
	}
	/**
	 * @return the email
	 */
	@Column(name="email" , length=23)
	public String getEmail() {
		return email;
	}
	/**
	 * @param email the email to set
	 */
	public void setEmail(String email) {
		this.email = email;
	}
	
}

 

 

JleeKey01.java代码：

package com.jlee03.compositeId;

import java.io.Serializable;

import javax.persistence.Embeddable;

/**
 * @author JLee
 * @since 2011-2-10
 */
@Embeddable
public class JleeKey01  implements Serializable{

	private static final long serialVersionUID = -3304319243957837925L;
	private long id ;
	private String name ;
	/**
	 * @return the id
	 */
	public long getId() {
		return id;
	}
	/**
	 * @param id the id to set
	 */
	public void setId(long id) {
		this.id = id;
	}
	/**
	 * @return the name
	 */
	public String getName() {
		return name;
	}
	/**
	 * @param name the name to set
	 */
	public void setName(String name) {
		this.name = name;
	}

	@Override
	public boolean equals(Object o) {
		if(o instanceof JleeKey01){
			JleeKey01 key = (JleeKey01)o ;
			if(this.id == key.getId() && this.name.equals(key.getName())){
				return true ;
			}
		}
		return false ;
	}
	
	@Override
	public int hashCode() {
		return this.name.hashCode();
	}
	
}

 

 

第二种写法：

Jlee02.java代码：

package com.jlee03.compositeId;

import javax.persistence.Column;
import javax.persistence.EmbeddedId;
import javax.persistence.Entity;
import javax.persistence.Table;

/**
 * @author JLee
 * @since 2011-2-10
 */
@Entity
@Table(name="JLEE02")
public class Jlee02 {

	private String address ;
	private int age ;
	private String email ;
	private String phone ;
	private JleeKey02 jleeKey ;
	
	/**
	 * @return the jleeKey
	 */
	@EmbeddedId
	public JleeKey02 getJleeKey() {
		return jleeKey;
	}
	/**
	 * @param jleeKey the jleeKey to set
	 */
	public void setJleeKey(JleeKey02 jleeKey) {
		this.jleeKey = jleeKey;
	}
	/**
	 * @return the phone
	 */
	@Column(name="phone" , length=20)
	public String getPhone() {
		return phone;
	}
	/**
	 * @param phone the phone to set
	 */
	public void setPhone(String phone) {
		this.phone = phone;
	}
	/**
	 * @return the address
	 */
	@Column(name="address" , length=50)
	public String getAddress() {
		return address;
	}
	/**
	 * @param address the address to set
	 */
	public void setAddress(String address) {
		this.address = address;
	}
	/**
	 * @return the age
	 */
	@Column(name="age")
	public int getAge() {
		return age;
	}
	/**
	 * @param age the age to set
	 */
	public void setAge(int age) {
		this.age = age;
	}
	/**
	 * @return the email
	 */
	@Column(name="email" , length=23)
	public String getEmail() {
		return email;
	}
	/**
	 * @param email the email to set
	 */
	public void setEmail(String email) {
		this.email = email;
	}
	
}

 

 

JleeKey02.java代码：

package com.jlee03.compositeId;

import java.io.Serializable;


/**
 * @author JLee
 */
public class JleeKey02 implements Serializable{

	private static final long serialVersionUID = -3236523319933461469L;
	private long id ;
	private String name ;
	/**
	 * @return the id
	 */
	public long getId() {
		return id;
	}
	/**
	 * @param id the id to set
	 */
	public void setId(long id) {
		this.id = id;
	}
	/**
	 * @return the name
	 */
	public String getName() {
		return name;
	}
	/**
	 * @param name the name to set
	 */
	public void setName(String name) {
		this.name = name;
	}

	@Override
	public boolean equals(Object o) {
		if(o instanceof JleeKey02){
			JleeKey02 key = (JleeKey02)o ;
			if(this.id == key.getId() && this.name.equals(key.getName())){
				return true ;
			}
		}
		return false ;
	}
	
	@Override
	public int hashCode() {
		return this.name.hashCode();
	}
	
}

 

 

第三种写法：

Jlee03.java代码：

package com.jlee03.compositeId;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.IdClass;
import javax.persistence.Table;

@Entity
@Table(name="JLEE03")
@IdClass(JleeKey03.class)
public class Jlee03 {

	private long id ;
	private String name ;
	
	/**
	 * @return the id
	 */
	@Id
	public long getId() {
		return id;
	}
	/**
	 * @param id the id to set
	 */
	public void setId(long id) {
		this.id = id;
	}
	/**
	 * @return the name
	 */
	@Id
	public String getName() {
		return name;
	}
	/**
	 * @param name the name to set
	 */
	public void setName(String name) {
		this.name = name;
	}
	private String address ;
	private int age ;
	private String email ;
	private String phone ;
	
	/**
	 * @return the phone
	 */
	@Column(name="phone" , length=20)
	public String getPhone() {
		return phone;
	}
	/**
	 * @param phone the phone to set
	 */
	public void setPhone(String phone) {
		this.phone = phone;
	}
	/**
	 * @return the address
	 */
	@Column(name="address" , length=50)
	public String getAddress() {
		return address;
	}
	/**
	 * @param address the address to set
	 */
	public void setAddress(String address) {
		this.address = address;
	}
	/**
	 * @return the age
	 */
	@Column(name="age")
	public int getAge() {
		return age;
	}
	/**
	 * @param age the age to set
	 */
	public void setAge(int age) {
		this.age = age;
	}
	/**
	 * @return the email
	 */
	@Column(name="email" , length=23)
	public String getEmail() {
		return email;
	}
	/**
	 * @param email the email to set
	 */
	public void setEmail(String email) {
		this.email = email;
	}
	
}

 

 

JleeKey03.java代码：

package com.jlee03.compositeId;

import java.io.Serializable;

/**
 * @author JLee
 */
public class JleeKey03 implements Serializable{

	private static final long serialVersionUID = 6060166117433738173L;
	private long id ;
	private String name ;
	/**
	 * @return the id
	 */
	public long getId() {
		return id;
	}
	/**
	 * @param id the id to set
	 */
	public void setId(long id) {
		this.id = id;
	}
	/**
	 * @return the name
	 */
	public String getName() {
		return name;
	}
	/**
	 * @param name the name to set
	 */
	public void setName(String name) {
		this.name = name;
	}

	@Override
	public boolean equals(Object o) {
		if(o instanceof JleeKey03){
			JleeKey03 key = (JleeKey03)o ;
			if(this.id == key.getId() && this.name.equals(key.getName())){
				return true ;
			}
		}
		return false ;
	}
	
	@Override
	public int hashCode() {
		return this.name.hashCode();
	}
	
}

 

 

联合主键必须重写 equals 和 hashCode 方法。

 

hibernate.cfg.xml配置文件：

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

    <session-factory>

        <!-- Database connection settings -->
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost/hibernate</property>
        <property name="connection.username">root</property>
        <property name="connection.password">root</property>

        <!-- JDBC connection pool (use the built-in) -->
        <property name="connection.pool_size">100</property>

        <!-- SQL dialect -->
        <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

        <!-- Enable Hibernate's automatic session context management -->
        <property name="current_session_context_class">thread</property>

        <!-- Disable the second-level cache  -->
        <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>
		
        <!-- Echo all executed SQL to stdout -->
        <property name="show_sql">true</property>

        <property name="format_sql">true</property>
		
        <!-- Drop and re-create the database schema on startup -->
        <!--<property name="hbm2ddl.auto">create</property>-->
		
		<mapping class="com.jlee03.compositeId.Jlee01"/>
		<mapping class="com.jlee03.compositeId.Jlee02"/>
		<mapping class="com.jlee03.compositeId.Jlee03"/>


    </session-factory>

</hibernate-configuration>

 

JleeTest.java代码：

package com.jlee03.compositeId;

import junit.framework.TestCase;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.tool.hbm2ddl.SchemaExport;

public class JleeTest extends TestCase {

	public void testJlee(){
		SessionFactory sf = new AnnotationConfiguration().configure().buildSessionFactory() ;
		Session session = sf.getCurrentSession() ;
		session.beginTransaction() ;
		
		Jlee01 jlee01 = new Jlee01() ;
		JleeKey01 key01 = new JleeKey01() ;
		key01.setId(0) ;
		key01.setName("jlee") ;
		jlee01.setJleeKey(key01) ;
		jlee01.setAddress("北京") ;
		jlee01.setAge(23) ;
		jlee01.setPhone("21321312321") ;
		
		Jlee02 jlee02 = new Jlee02() ;
		JleeKey02 key02 = new JleeKey02() ;
		key02.setId(0) ;
		key02.setName("jlee") ;
		jlee02.setJleeKey(key02) ;
		jlee02.setAddress("上海") ;
		jlee02.setAge(32) ;
		jlee02.setEmail("[e-mail]") ;
		
		Jlee03 jlee03 = new Jlee03() ;
		jlee03.setId(1) ;
		jlee03.setName("jlee") ;
		jlee03.setAddress("这里") ;
		jlee03.setAge(32) ;
		jlee03.setEmail("[e-mail]") ;
		
		session.save(jlee01) ;
		session.save(jlee02) ;
		session.save(jlee03) ;
		
		session.getTransaction().commit() ;
		
	}
	
	public void testExport(){
		new SchemaExport(new AnnotationConfiguration().configure()).create(false, true) ;
	}
	
}

 

评论

1 楼 深夜的清风 2012-10-11  

哪个是主表那个是子表