1. TreeMap（TreeMap<Student，String>）的案例
2. 案例代码：
（1）Student.java：
package cn.itcast_04;
public class Student {
private String name;
private int age;
public Student() {
super();
}
public Student(String name, int age) {
super();
this.name = name;
this.age = age;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}
（2）测试类TreeMapDemo2，如下：
package cn.itcast_04; import java.util.Comparator;
import java.util.Set;
import java.util.TreeMap; /*
* TreeMap<Student,String>
* 键:Student
* 值：String
*/
public class TreeMapDemo2 {
public static void main(String[] args) {
// 创建集合对象
TreeMap<Student, String> tm = new TreeMap<Student, String>(
new Comparator<Student>() {
@Override
public int compare(Student s1, Student s2) {
// 主要条件
int num = s1.getAge() - s2.getAge();
// 次要条件
int num2 = num == 0 ? s1.getName().compareTo(
s2.getName()) : num;
return num2;
}
}); // 创建学生对象
Student s1 = new Student("潘安", 30);
Student s2 = new Student("柳下惠", 35);
Student s3 = new Student("唐伯虎", 33);
Student s4 = new Student("燕青", 32);
Student s5 = new Student("唐伯虎", 33); // 存储元素
tm.put(s1, "宋朝");
tm.put(s2, "元朝");
tm.put(s3, "明朝");
tm.put(s4, "清朝");
tm.put(s5, "汉朝"); // 遍历
Set<Student> set = tm.keySet();
for (Student key : set) {
String value = tm.get(key);
System.out.println(key.getName() + "---" + key.getAge() + "---"
+ value);
}
}
}
运行效果，如下：