74 lines
1.7 KiB
Java
74 lines
1.7 KiB
Java
package chapter6;
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import java.util.HashSet;
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import java.util.Iterator;
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class Student implements Comparable<Student> {
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String id;
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String name;
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int height;
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public Student(String id, String name) {
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this.id = id;
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this.name = name;
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}
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public void setHeight(int height) {
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this.height = height;
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}
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public String toString() {
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return id + ":" + name;
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}
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public int hashCode() {
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return id.hashCode();
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}
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public boolean equals(Object obj) {
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if (this == obj) {
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return true;
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}
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if (!(obj instanceof Student)) {
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return false;
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}
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Student other = (Student) obj;
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return this.id.equals(other.id);
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}
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public int compareTo(Student other) {
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if (this.height > other.height) {
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return 1; // 返回正数：表示"我"比"你"大
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} else if (this.height < other.height) {
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return -1; // 返回负数：表示"我"比"你"小
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} else {
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return 0; // 返回0：表示"我"和"你"一样大
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}
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}
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}
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public class Example08 {
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public static void main(String[] args) {
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HashSet<Student> students = new HashSet<>();
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Student s1 = new Student("1", "张三");
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Student s2 = new Student("2", "李四");
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Student s3 = new Student("2", "李四");
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Student s4 = new Student("3", "王五");
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students.add(s3);
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students.add(s4);
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students.add(s1);
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students.add(s2);
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Iterator<Student> iterator = students.iterator();
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while (iterator.hasNext()) {
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Student student = iterator.next();
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System.out.println(student);
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}
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}
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}
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