小白笔记----------------对象equals方法的使用

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mark一下，免的以后忘了

import java.util.*;public class testCollection {public static void main(String[] args) {Collection c = new HashSet();c.add("Hello");c.add(new Name("Aaron","qj"));c.add(new Integer(100));c.remove("Hello");//c.remove(new Name("Aaron","qj")); System.out.println(c.remove(new Name("Aaron", "qj")));System.out.println(c.size());System.out.println(c);}}class Name{/*两个对象如果相等那么他们的Hashcode也应该相等*/private String firstName,lastName;public Name(String firstName,String lastName){this.firstName = firstName;this.lastName = lastName;}public String getFirstName(){return firstName;}public String getLastName(){return lastName;}public String toString(){return firstName+" "+lastName;}public  boolean equals(Object obj){if(obj instanceof Name){Name name = (Name)obj;return (firstName.equals(name.firstName))&&(lastName.equals(name.lastName));}return super.equals(obj);}public int hashCode(){return lastName.hashCode();}}

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