Hibernate逍遥游记-第12章 映射值类型集合-005对集合排序(<order-by><sort>)

1.

2.

<?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 >

  <class name="mypack.Monkey" table="MONKEYS" >
    <id name="id" type="long" column="ID">
      <generator class="increment"/>
    </id>

    <property name="name" type="string" >
        <column name="NAME" length="15" />
    </property>

   <property name="age" type="int" >
        <column name="AGE" />
   </property>

      
   <set   name="images"   table="IMAGES"    lazy="true" sort="natural" >
   
   <!--
   <set   name="images"   table="IMAGES"    lazy="true" sort="mypack.ReverseStringComparator">
   -->
   
     <key column="MONKEY_ID" />
        <element column="FILENAME" type="string"  not-null="true"/>
   </set>   
   
  </class>
 
</hibernate-mapping>

3.

package mypack;

import java.io.Serializable;
import java.util.Set;
import java.util.TreeSet;

public class Monkey implements Serializable {
    private Long id;
    private String name;
    private int age;
    private Set images=new TreeSet();

    /** full constructor */
    public Monkey(String name, int age,Set images) {
        this.name = name;
        this.age=age;
        this.images = images;
    }

    /** default constructor */
    public Monkey() {
    }

    /** minimal constructor */
    public Monkey(Set images) {
        this.images = images;
    }

    public Long getId() {
        return this.id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return this.name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return this.age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public Set getImages() {
        return this.images;
    }

    public void setImages(Set images) {
        this.images = images;
    }

}

4.

package mypack;

import java.util.*;
public class ReverseStringComparator implements Comparator{

  public int compare(Object o1,Object o2){
    String s1=(String)o1;
    String s2=(String)o2;

    if(s1.compareTo(s2)>0) return -1;
    if(s1.compareTo(s2)<0) return 1;

    return 0;
  }
}

5.