如何删除ArrayList中的重复元素

/**
* 2017年10月7日 上午11:33:57
* mischen
*/
package com.mischen.cn;

import java.util.ArrayList;
import java.util.Iterator;

class Book{
int id;
String  name;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Book(int id, String name) {
this.id = id;
this.name = name;
}
@Override
public String toString() {
return " [书号=" + id + ", 书名=" + name + "]";
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + id;
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
Book other = (Book) obj;
if (id != other.id)
return false;
return true;
}
}
/**
* @author mischen
* 2017年10月7日 上午11:33:57
*/
public class Demo4 {
public static void main(String[] args){
ArrayList list=new ArrayList();
list.add(new Book(110, "Java编程思想"));
list.add(new Book(120, "Java初级"));
list.add(new Book(130, "Java高级"));
list.add(new Book(110, "深入Java"));
ArrayList list2=claerRepeat(list);
System.out.println("新集合的元素"+list2);
}
public static ArrayList claerRepeat(ArrayList list){
ArrayList newsList=new ArrayList<>();
Iterator iterator=list.iterator();
while(iterator.hasNext()){
Book book=(Book) iterator.next();
if(!newsList.contains(book)){
newsList.add(book);
}
}
return newsList;
}
}