List遍历的几种方式以及几种基本的增删改查

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import java.util.ArrayList;import java.util.Iterator;import java.util.List;public class ListTest {public static void main(String[] args) {List<Person> list = new ArrayList<>();Person p1 = new Person("zhouyu", 22, "jiangsu");Person p2 = new Person("liubei", 33, "sichuan");Person p3 = new Person("caocao", 44, "henan");list.add(p1);list.add(p2);list.add(p3);Iterator<Person> iterator = list.iterator();// 方式1 迭代器while (iterator.hasNext()) {Person person = iterator.next();System.out.println(person);}System.out.println("-+_+_+_+_+_+_+_-");// 方式2 普通forfor (int i = 0; i < list.size(); i++) {Person person = (Person) list.get(i);System.out.println(person);}System.out.println("-+_+_+_+_+_+_+_-");// 方式3 增强forfor (Object object : list) {Person person = (Person) object;System.out.println(person);}System.out.println("-+_+_+_+_+_+_+_-");Person person = new Person("zhangsan", 23, "zhangcun");// 列表的修改功能list.set(2, person);// 自带的toString方法System.out.println(list.toString());System.out.println("-+_+_+_+_+_+_+_-");// 列表的截取功能 从指定位置开始截取到指定位置结束System.out.println(list.subList(1, 3));// [Person [name=liubei, age=33, address=sichuan], Person// [name=zhangsan, age=23, address=zhangcun]]// 获取指定索引 的元素System.out.println(list.get(0));}}

package cn.spring01.ArrayList;public class Person {private String name;private int age;private String address;@Overridepublic String toString() {return "Person [name=" + name + ", age=" + age + ", address=" + address + "]";}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;}public String getAddress() {return address;}public void setAddress(String address) {this.address = address;}public Person(String name, int age, String address) {super();this.name = name;this.age = age;this.address = address;}}

打印结果：

Person [name=zhouyu, age=22, address=jiangsu]

Person [name=liubei, age=33, address=sichuan]

Person [name=caocao, age=44, address=henan]

-+_+_+_+_+_+_+_-

Person [name=zhouyu, age=22, address=jiangsu]

Person [name=liubei, age=33, address=sichuan]

Person [name=caocao, age=44, address=henan]

-+_+_+_+_+_+_+_-

Person [name=zhouyu, age=22, address=jiangsu]

Person [name=liubei, age=33, address=sichuan]

Person [name=caocao, age=44, address=henan]

-+_+_+_+_+_+_+_-

[Person [name=zhouyu, age=22, address=jiangsu], Person [name=liubei, age=33, address=sichuan], Person [name=zhangsan, age=23, address=zhangcun]]

-+_+_+_+_+_+_+_-

[Person [name=liubei, age=33, address=sichuan], Person [name=zhangsan, age=23, address=zhangcun]]

Person [name=zhouyu, age=22, address=jiangsu]

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