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周遊List和Map集合,周遊數組Map集合:周遊數組:

第一種方法:for-each(加強for循環)

package list;

import java.util.ArrayList;
import java.util.List;

public class ListArray {

	public static void main(String[] args) {
		
		List<Object> listArray = new ArrayList<Object>();
		listArray.add("唐斐");
		listArray.add(521);
		listArray.add(new String("簡兮"));
		for(Object data :listArray){
			System.out.println(data);
		}
	}
}
           

第二種方法:疊代器

package list;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

public class ListArray {

	public static void main(String[] args) {
		
		List<Object> listArray = new ArrayList<Object>();
		listArray.add("唐斐");
		listArray.add(521);
		listArray.add(new String("簡兮"));
		Iterator<Object> iterator = listArray.iterator();
		while(iterator.hasNext()){
			Object data = iterator.next();
			System.out.println(data);
		}
	}
}
           

第三種方法:jsp/jstl  <c:forEach></c:forEach> 

<%@ page language="java" contentType="text/html; charset=UTF-8"  pageEncoding="UTF-8"%>
<%@ page import="java.util.List"%>
<%@ page import="java.util.ArrayList"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>   
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
	<head>
		<title>List周遊</title>
	</head>
	<body>
		<%  
    		List<String> name = new ArrayList<String>();  
    		name.add("zhangSan");  
    		name.add("liSi");  
    		name.add("wangWu");  
    		name.add("zhaoLiu");  
    		pageContext.setAttribute("ns", name);  
		%>  
		<c:forEach var="item" items="${ns }">  
    		<c:out value="name: ${item }"/><br/>  
		</c:forEach>  
	</body>
</html>
           

Map集合:

第一種方法:for-each(加強for循環)

package map;

import java.util.HashMap;
import java.util.Map;
import java.util.Set;

public class MapArray {

	public static void main(String[] args) {
		
		Map<Integer,String> hashMap = new HashMap<Integer,String>();
		hashMap.put(1, "丹");
		hashMap.put(2, "頂");
		hashMap.put(3, "鶴");
		Set<Integer> setKey = hashMap.keySet();
		for	(Integer key : setKey){
			String value = hashMap.get(key);
			System.out.println(key+"~~~"+value);
		}
	}
}
           

第二種方法: 疊代器

package map;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;

public class MapArray {

	public static void main(String[] args) {
		
		Map<Integer,String> hashMap = new HashMap<Integer,String>();
		hashMap.put(1, "丹");
		hashMap.put(2, "頂");
		hashMap.put(3, "鶴");
		Set<Integer> setKey = hashMap.keySet();
		Iterator<Integer> iterator = setKey.iterator();
		while(iterator.hasNext()){
			Integer key = iterator.next();
			String value = hashMap.get(key);
			System.out.println(key+"~~~"+value);
		}
	}
}
           

第三種方法:泛型,類型Entry,for-each(加強for循環)

package map;

import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

public class MapArray {

	public static void main(String[] args) {
		
		Map<Integer,String> hashMap = new HashMap<Integer,String>();
		hashMap.put(1, "丹");
		hashMap.put(2, "頂");
		hashMap.put(3, "鶴");
		Set<Entry<Integer,String>> set = hashMap.entrySet();
		for(Entry<Integer,String> entry : set){
			Integer key = entry.getKey();
			String value = entry.getValue();
			System.out.println(key+"~~~"+value);
		}
		
	}
}
           

第四種方法:泛型,類型Entry,疊代器

package map;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

public class MapArray {

	public static void main(String[] args) {
		
		Map<Integer,String> hashMap = new HashMap<Integer,String>();
		hashMap.put(1, "丹");
		hashMap.put(2, "頂");
		hashMap.put(3, "鶴");
		Set<Entry<Integer,String>> set = hashMap.entrySet();
		Iterator<Entry<Integer,String>> iterator = set.iterator();
		while(iterator.hasNext()){
			Entry<Integer,String> entry = iterator.next();
			Integer key = entry.getKey();
			String value = entry.getValue();
			System.out.println(key+"~~~"+value);
		}
	}
}
           

第五種方法:jsp/jstl  <c:forEach></c:forEach>

<%@ page language="java" contentType="text/html; charset=UTF-8"  pageEncoding="UTF-8"%>
<%@ page import="java.util.Map"%>
<%@ page import="java.util.LinkedHashMap"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>   
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
	<head>
		<title>Map周遊</title>
	</head>
	<body>
		<%  
    		Map<String,String> stu = new LinkedHashMap<String,String>();  
    		stu.put("number", "001");  
    		stu.put("name", "zhangSan");  
    		stu.put("age", "23");  
    		stu.put("sex", "male");  
    		pageContext.setAttribute("stu", stu);  
		%>  
		<c:forEach var="item" items="${stu }">  
    		<c:out value="${item.key }: ${item.value }"/><br/>  
		</c:forEach>  
	</body>
</html>
           

周遊數組:

第一種方法:普通for循環

package array;

public class array {

	public static void main(String[] args) {
		
		Object [] array = new Object[]{1,"a",new String("d")};
		for(int i = 0;i<array.length;i++){
			System.out.println(array[i]);
		}
	}
}
           

第二種方法:for-each

package array;

public class array {

	public static void main(String[] args) {
		
		Object [] array = new Object[]{1,"a",new String("d")};
		for(Object data : array){
		System.out.println(data);
		}
	}
}
           

第三種方法:jsp/jstl  <c:forEach></c:forEach>

<%@ page language="java" contentType="text/html; charset=UTF-8"  pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>   
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
	<head>
		<title>數組周遊</title>
	</head>
	<body>
		<%  
			String[] name = {"唐斐", "簡兮", "安心", "柯洛"};  
			pageContext.setAttribute("ns", name);  
		%>  
		<c:forEach var="item" items="${ns}">  
    		<c:out value="name: ${item}"/><br/>  
		</c:forEach> 
	</body>
</html>