List去除重复元素

原理根据Set的特性，另外需要重写对象的hashCode()方法和equals()方法

代码如下

package com.pingan.home.tets;

import java.util.ArrayList;
import java.util.LinkedHashSet;
import java.util.Set;

public class Person {

	private String name;
	private String addr;

	public Person(String name, String addr) {
		super();
		this.name = name;
		this.addr = addr;
	}

	public String getName() {
		return name;
	}

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

	public String getAddr() {
		return addr;
	}

	public void setAddr(String addr) {
		this.addr = addr;
	}

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((addr == null) ? 0 : addr.hashCode());
		result = prime * result + ((name == null) ? 0 : name.hashCode());
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		Person other = (Person) obj;
		if (addr == null) {
			if (other.addr != null)
				return false;
		} else if (!addr.equals(other.addr))
			return false;
		if (name == null) {
			if (other.name != null)
				return false;
		} else if (!name.equals(other.name))
			return false;
		return true;
	}

	public static void main(String[] args) {
		ArrayList<Person> persoList = new ArrayList<Person>();
		for (int i = 0; i < 10; i++) {
			Person p = new Person("w", "j" + i);
			persoList.add(p);
		}
		Person p1 = new Person("w", "j" + 1);
		Person p2 = new Person("w", "j" + 5);
		Person p3 = new Person("w", "j" + 0);
		Person p4 = new Person("w", "j" + 9);
		persoList.add(p1);
		persoList.add(p2);
		persoList.add(p3);
		persoList.add(p4);
		System.out.println("persoList.size() s：" + persoList.size());
		Set<Person> set = new LinkedHashSet<Person>(persoList);
		persoList.clear();
		persoList.addAll(set);
		System.out.println("persoList.size() e：" + persoList.size());
	}
}