java list的作用_java list 起到什么作用 List al = new ArrayList();又起到什么作用

//写个简单的例子给你看看

//Person类：

package test;

public class Person {

private String personName;

private int personAge;

private int personSex;//0 for male, 1 for female

public Person(){

}

public Person(String personName, int personAge, int personSex) {

this.personName = personName;

this.personAge = personAge;

this.personSex = personSex;

}

public String getPersonName() {

return personName;

}

public void setPersonName(String personName) {

this.personName = personName;

}

public int getPersonAge() {

return personAge;

}

public void setPersonAge(int personAge) {

this.personAge = personAge;

}

public int getPersonSex() {

return personSex;

}

public void setPersonSex(int personSex) {

this.personSex = personSex;

}

@Override

public String toString() {

return "Person [personAge=" + personAge + ", personName=" + personName

+ ", personSex=" + personSex + "]";

}

}

//Test类：

package test;

import java.util.List;

import java.util.ArrayList;

public class Test {

public static void main(String []args){

Test test=new Test();

test.assemblePersonList();

}

private void assemblePersonList(){

List personList=new ArrayList();

Person person=new Person("Person2",22,1);

personList.add(person);

person.setPersonName("Person2");

person.setPersonAge(20);

person.setPersonSex(0);

personList.add(person);

person.setPersonName("Person3");

person.setPersonAge(24);

person.setPersonSex(1);

personList.add(person);

person.setPersonName("Person4");

person.setPersonAge(24);

person.setPersonSex(0);

personList.add(person);

for(int i=0;i

System.out.println(personList.get(i));

}

}

}