增强for循环

增强for循环

**语法：** 


for(数据类型 变量1 ：数组/集合){

    System.out.println(变量1); //直接打印变量1              
    
}

package Foreach;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

import domain.Student;

public class ForeachTest {

	/**
	 * 增强for循环 foreach()
	 * 语法：
	 * for(数据类型 变量1 ：数组/集合){
	 * 	System.out.println(变量1); //直接打印变量1
	 * }
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		ForeachTest ft = new ForeachTest();
		//遍历数组
		System.out.println("两种数组类型的遍历");
		//String类型 
		ft.eactArray();
		//Student对象类型 
		ft.eactStudent();
		
		//集合遍历
		System.out.println("三种集合框架的遍历");
		//遍历List
		eactList();
		
		//遍历set
		eactSet();
		
		//遍历map
		eactMap();
		
	}
	
	
	//遍历String类型的数组
	public void eactArray(){
		String[] str = {"蜘蛛侠","闪电侠","煎饼侠","钢铁侠"};
		
		System.out.println("//遍历String类型的数组");
		for(String s : str){
			System.out.println(s);
		}
	}
	
	//遍历对象
	public void eactStudent(){
		Student[] str = new Student[4];
		str[0] = new Student("蜘蛛侠");
		str[1] = new Student("闪电侠");
		str[2] = new Student("煎饼侠");
		str[3] = new Student("钢铁侠");
		
		System.out.println("//遍历对象");
		for(Student s : str){
			System.out.println(s);
		}
	}

	//遍历List、set、map集合
	
	//遍历set集合
	public static void eactList(){
		List<String> list = new ArrayList<String>();
		list.add("蜘蛛侠");
		list.add("闪电侠");
		list.add("煎饼侠");
		list.add("钢铁侠");
	
		System.out.println("//遍历set集合");
		for(String s : list){
			System.out.println(s);
		}
	}
	
	//遍历set集合
	public static void eactSet(){
		Set<String> set = new HashSet<String>();
		set.add("蜘蛛侠");
		set.add("闪电侠");
		set.add("煎饼侠");
		set.add("钢铁侠");
	
		System.out.println("//遍历set集合");
		for(String s : set){
			System.out.println(s);
		}
	}
	
	//遍历map集合
	public static void eactMap(){
		
		Map<Integer,String> map = new HashMap<Integer,String>();
		map.put(1,"蜘蛛侠");
		map.put(2,"闪电侠");
		map.put(3,"煎饼侠");
		map.put(4,"钢铁侠");
		Set<Integer> set = map.keySet();
	
		System.out.println("//遍历map集合");
		for(Integer s : set){
			System.out.println(map.get(s));
		}
	}
	
	
	
}