集合遍历的方法

package lianxi1;

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

import org.junit.Test;

public class TestIterator {
@Test
    public void test1(){
       Collection coll2 = new ArrayList();
       coll2.add(55);
       coll2.add(35.432);
       coll2.add("rr");
       coll2.add(new Student("3001","wu"));
       //方法一
       Iterator ite = coll2.iterator();
       while(ite.hasNext()){
           System.out.println(ite.next());
       }
       //方法二：使用增强for循环
       for(Object i:coll2){   //只是将coll2值赋给i，并不影响原集合中的值
           i = 3;
           System.out.println(i);
       }
       Iterator ite2 = coll2.iterator();
       while(ite2.hasNext()){
           System.out.println(ite2.next());
       }
       
    }
}