遍历嵌套集合

package niu.cheng5;

import java.util.ArrayList;

import java.util.Iterator;

//遍历嵌套集合

public class ArrayListTest {

/**

* @param args

*/

public static void main(String[] args) {

// TODO Auto-generated method stub

ArrayList<ArrayList<Student>> a=new ArrayList<ArrayList<Student>>();

ArrayList<Student> a2=new ArrayList<Student>();

ArrayList<Student> a3=new ArrayList<Student>();

ArrayList<Student> a4=new ArrayList<Student>();

Student s1=new Student("axx",10);

Student s2=new Student("bxx",11);

Student s3=new Student("cxx",12);

Student s4=new Student("dxx",13);

Student s5=new Student("exx",11);

Student s6=new Student("fxx",12);

Student s7=new Student("gxx",13);

Student s8=new Student("hxx",11);

Student s9=new Student("ixx",12);

Student s10=new Student("jxx",13);

a2.add(s1);

a2.add(s2);

a2.add(s3);

a2.add(s4);

a3.add(s5);

a3.add(s6);

a3.add(s7);

a4.add(s8);

a4.add(s9);

a4.add(s10);

a.add(a2);

a.add(a3);

a.add(a4);

for(ArrayList<Student> x:a){

/*

//方式1

for(int n=0;n<x.size();n++){

Student s=x.get(n);

System.out.println(s.getName()+"--"+s.getAge());

}

*/

/*

//方式2

for(Student y:x){

System.out.println(y.getName()+"--"+y.getAge());

}

*/

//方式3

Iterator<Student> l=x.iterator();

while(l.hasNext()){

Student s=l.next();

System.out.println(s.getName()+"--"+s.getAge());

}

}

}

}