Ò׽ؽØÍ¼Èí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

JavaʵÏÖ½«Mapת»»ÎªListµÄС´úÂë

import java.util.ArrayList; 
import java.util.HashMap; 
import java.util.Iterator; 
import java.util.List; 
import java.util.Map; 
public class ConvertMapToList {
    /**
     * ʵÏÖ½«HashMapת»»³ÉΪArrayList£¬²¢½«mapµÄKey ¡¢Value·Ö±ð´æ·Åµ½Á½¸öArrayListµ±ÖÐ
     * @param args
     */
    public static void main(String[] args) {
        Map map = new HashMap();
        map.put("a", "a1");
        map.put("b", "b1");
        map.put("c", "c1");
        List listKey = new ArrayList();
        List listValue = new ArrayList();
        Iterator it = map.keySet().iterator();
        while (it.hasNext()) {
            String key = it.next().toString();
            listKey.add(key);
            listValue.add(map.get(key));
        }
        System.out.println("Convert Finished !");
        
        //output the context of the ArrayList
        for(int i =0 ;i<listKey.size();i++){
            System.out.print("Key :"+listKey.get(i));
            System.out.println("     Value :"+listValue.get(i));
        }
    }
}


Ïà¹ØÎĵµ£º

javaÈëÃÅ

 Javaѧϰ´ÓÈëÃŵ½¾«Í¨ 
Ò»¡¢ JDK (Java Development Kit) 
JDKÊÇÕû¸öJavaµÄºËÐÄ£¬°üÀ¨ÁËJavaÔËÐл·¾³£¨Java Runtime Envirnment£©£¬Ò»¶ÑJava¹¤¾ßºÍJava»ù´¡µÄÀà¿â(rt.jar)¡£²»ÂÛʲôJavaÓ¦Ó÷þÎñÆ÷ʵÖʶ¼ÊÇÄÚÖÃÁËij¸ö°æ±¾µÄJDK¡£Òò´ËÕÆÎÕJDKÊÇѧºÃJavaµÄµÚÒ»²½¡£×îÖ÷Á÷µÄJ ......

java»ù´¡ÎÊ´ð£¨3£©

21¡¢Static Nested Class ºÍ Inner ClassµÄ²»Í¬¡£ Static Nested ClassÊDZ»ÉùÃ÷Ϊ¾²Ì¬£¨static£©µÄÄÚ²¿À࣬Ëü¿ÉÒÔ²»ÒÀÀµÓÚÍⲿÀàʵÀý±»ÊµÀý»¯¡£¶øÍ¨³£µÄÄÚ²¿ÀàÐèÒªÔÚÍⲿÀàʵÀý»¯ºó²ÅÄÜʵÀý»¯¡£
 22¡¢JSPÖж¯Ì¬INCLUDEÓ뾲̬INCLUDEµÄÇø±ð£¿¶¯Ì¬INCLUDEÓÃjsp:include¶¯×÷ʵÏÖ Ëü×ÜÊÇ»á¼ì²éËùº¬ÎļþÖеı仯£¬ÊʺÏÓÃÓÚ ......

Java synchronizedÓ÷¨

synchronized¹Ø¼ü×ÖÔÚ¶àÏß³ÌÖеÄ×÷Óãº
Á½ÖÖÓ÷¨£ºsynchronized ·½·¨ºÍ synchronized ¿é¡£
1. synchronized ·½·¨£ºÍ¨¹ýÔÚ·½·¨ÉùÃ÷ÖмÓÈë synchronized¹Ø¼ü×ÖÀ´ÉùÃ÷ synchronized ·½·¨¡£ÈçÉÏÊöÀý×ÓËùÊö¡£
synchronized ·½·¨¿ØÖƶÔÀà³ÉÔ±±äÁ¿µÄ·ÃÎÊ£ºÃ¿¸öÀàʵÀý¶ÔÏó¶ÔÓ¦Ò»°ÑËø£¬Ã¿¸ö synchronized ·½·¨¶¼±ØÐë»ñµÃµ÷Óø÷½· ......

javaÖÐmap¼¯ºÏµÄÓ÷¨

1.ÉùÃ÷Ò»¸ömap: Map map = new HashMap();
2.ÏòmapÖзÅÖµ,×¢Ò⣺mapÊÇkey-valueµÄÐÎʽ´æ·ÅµÄ.Èç:
     map.put("sa","dd");
3.´ÓmapÖÐȡֵ:String str = map.get("sa").toString();½á¹ûÊÇ:str = "dd";
4.±éÀúÒ»¸ömap£¬´ÓÖÐÈ¡µÃkey ºÍvalue
JDK1.5
Map m = new HashMap();
for ( ......

java ÖÐ Map±éÀú


µÚ¶þÖÖ·½·¨Ð§Âʸü¸ß
·¨¢Ù
Map map = new HashMap();
    Iterator it = map.entrySet().iterator();
    while (it.hasNext()) {
        Map.Entry entry = (Map.Entry) it.next();
        Object key = e ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ