转发自 https://blog.csdn.net/guominjin/article/details/78963578
1>:首先将要作为主键的属性首先抽取成单独的实体 并提供get And set方法 并且还需要序列化
比如现在有一个实体 People ,具有属性pName,pAddress,pJavaScore,pCscore
复合主键为pName,pAddress
**********将这两个属性抽离形成一个新的实体并提供setter,gettter方法实现序列化（坑区）
compositionkey.java
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import java.io.Serializable;
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/**
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*
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* @author Guomin JIn
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*
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*/
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public
class CompositionKey implements Serializable{
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private String pName;
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private String pAddress;
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public String getpName() {
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return pName;
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}
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public void setpName(String pName) {
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this.pName = pName;
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}
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public String getpAddress() {
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return pAddress;
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}
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public void setpAddress(String pAddress) {
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this.pAddress = pAddress;
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}
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}
2>:在实际的实体中申明主键实体的变量
抽离之后的Peopel实体如下:
People.java
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package cn.pzhu.composition;
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/**
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* 实体类
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* @author Guomin JIn
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*
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*/
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public
class People {
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private CompositionKey key;
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private
float pJavaScore;
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private
float pCScore;
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public CompositionKey getKey() {
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return key;
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}
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public void setKey(CompositionKey key) {
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this.key = key;
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}
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public float getpJavaScore() {
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return pJavaScore;
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}
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public void setpJavaScore(float pJavaScore) {
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this.pJavaScore = pJavaScore;
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}
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public float getpCScore() {
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return pCScore;
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}
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public void setpCScore(float pCScore) {
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this.pCScore = pCScore;
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}
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@Override
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public String toString() {
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return
"People [key=" + key +
", pJavaScore=" + pJavaScore +
", pCScore=" + pCScore +
"]";
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}
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}
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3>:在映射文件中编写实体的配置文件
配置文件如下：
hibernate.cfg.xml省略()
people.hbm.xml
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<?xml version="1.0"?>
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<!DOCTYPE hibernate-mapping PUBLIC
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"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
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"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
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<hibernate-mapping package="cn.pzhu.composition">
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<class name="People" table="peopel" >
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<composite-id name="key">
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<key-property name="pName" length="10" type="java.lang.String">
</key-property>
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<key-property name="pAddress" length="10" type="java.lang.String">
</key-property>
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</composite-id>
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<property name="pJavaScore" length="5"/>
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<property name="pCScore">
</property>
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</class>
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</hibernate-mapping>
测试类使用junit
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@Test
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public void test_0001() {
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Session session=
new Configuration()
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.configure(
"hibernate.cfg.xml")
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.addClass(People.class)
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.buildSessionFactory()
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.openSession();
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session.beginTransaction();
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CompositionKey key=
new CompositionKey();
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key.setpName(
"jgm");
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key.setpAddress(
"chengdu");
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People people=
new People();
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people.setKey(key);
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people.setpJavaScore(
12.34f);
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people.setpCScore(
36.2f);
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//HibernateUtil.save(people);
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session.save(people);
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}