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1、java中集合的遍历publicclass Test3 publicstaticvoid main(String args) List l = new ArrayList;l.add(世界你好！);l.add(上海);for (int i = 0; i < l.size; i+) / 普通的for循环取出集合中的元素System.out.print(l.get(i);System.out.println;for (Object o : l) / 增强for循环取出集合中的元素System.out.print(o);System.out.println;for (Iterator it =
2、l.iterator; it.hasNext;) / 利用迭代器取出集合中的元素System.out.print(it.next);System.out.println;Iterator it = l.iterator; /利用迭代器取出集合中的元素while (it.hasNext) System.out.print(it.next);java中遍历MAP的几种方法1. Map<String,String> map=new HashMap<String,String 2. map.put(username, qq); 3. map.put(passWord, 123); 4. m
3、ap.put(userID, 1); 5. map.put(email, qq); Map<String,String> map=new HashMap<String,Stringmap.put(username, qq);map.put(passWord, 123);map.put(userID, 1);map.put(email, qq);第一种用for循环Java代码1. for(Map.Entry<String, String> entry:map.entrySet) 2. System.out.println(entry.getKey+->+entry.get
4、Value); 3. for(Map.Entry<String, String> entry:map.entrySet)System.out.println(entry.getKey+->+entry.getValue);第二种用迭代Java代码1. Set set = map.entrySet; 2. Iterator i = set.iterator; 3. while(i.hasNext) 4. Map.Entry<String, String> entry1=(Map.Entry<String, String>)i.next; 5. System.out.p
5、rintln(entry1.getKey+=+entry1.getValue); 6. Set set = map.entrySet; Iterator i = set.iterator; while(i.hasNext) Map.Entry<String, String> entry1=(Map.Entry<String, String>)i.next;System.out.println(entry1.getKey+=+entry1.getValue);用keySet迭代Java代码1. Iterator it=map.keySet.iterator; 2. while(i
6、t.hasNext) 3. String key; 4. String value; 5. key=it.next.toString; 6. value=map.get(key); 7. System.out.println(key+-+value); 8. Iterator it=map.keySet.iterator;while(it.hasNext)String key;String value;key=it.next.toString;value=map.get(key);System.out.println(key+-+value);用entrySet迭代Java代码1. Itera
7、tor it=map.entrySet.iterator; 2. System.out.println( map.entrySet.size); 3. String key; 4. String value; 5. while(it.hasNext) 6. Map.Entry entry = (Map.Entry)it.next; 7. key=entry.getKey.toString; 8. value=entry.getValue.toString; 9. System.out.println(key+=+value); 10. package com.sina.www;import j
8、ava.util.HashMap;import java.util.Iterator;import java.util.Map;import java.util.Set;public class MapTest2 public static void main(String args) Map<String, String> m = new HashMap<String, String/ m.put(001, new Person(关羽, 23);/ m.put(002, new Person(刘备, 24);/ m.put(003, new Person(百度, 22);/ m.
9、put(sa, 123);m.put(sb, 143);m.put(sc, 153);m.put(sd, 184);Set keyset = m.keySet; / 对Map集合的迭代方法一keyset 迭代Iterator it = keyset.iterator;while (it.hasNext) String p = (String) it.next;System.out.print(value= + m.get(p) + );/ System.out.println(m.get(sa);Iterator it2 = m.entrySet.iterator; / Map集合的迭代方法二
10、entrySet迭代System.out.println;System.out.println(长度为 + m.entrySet.size);String key;String value;while (it2.hasNext) Map.Entry entry = (Map.Entry) it2.next;key = entry.getKey.toString;value = entry.getValue.toString;System.out.print(key + = + value + );System.out.println;System.out.println(-);for (Map.Entry entry : m.entrySet) / / Map集合的迭代方法三for循环迭代System.out.print(entry.getKey + = + entry.getValue + );
