Hibernate映射到多列时候,作为主键,对应的组件应该实现序列化。否则会出错
Person.java
package zcw;
public class Person implements java.io.Serializable{
// 多列作为联合组件
private String first;
private String last;
private int age;
public Person(){}
public Person(String first,String last,int age){
this.first = first;
this.last = last;
this.age = age;
}
public String getFirst() {
return first;
}
public void setFirst(String first) {
this.first = first;
}
public String getLast() {
return last;
}
public void setLast(String last) {
this.last = last;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
@Override
public boolean equals(Object obj) {
if(this == obj){
return true;
}
if(obj != null && obj.getClass() == Person.class){
Person target = (Person)obj;
if(target.getFirst().endsWith(this.getFirst())
&& target.getLast().endsWith(this.getLast())){
return true;
}
}
return false;
}
@Override
public int hashCode() {
return this.getFirst().hashCode()*7+this.getLast().hashCode();
}
}
实现序列化算法,重写hashcode和equals方法,可以对应着不同的改写此两个方法
对应的xml文件Person.htm.xml
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="zcw">
<class name="Person">
<composite-id>
<key-property name="first" type="string"/>
<key-property name="last" type="string"/>
</composite-id>
<property name="age" type="int"/>
</class>
</hibernate-mapping>