13¡¢JAVAÖеļ¯ºÏÀà
¼¯ºÏÀàÊÇÒ»×éÓÃÓÚ´æ´¢Ò»×é¶ÔÏ󣬯äÖеÄÿ¸ö¶ÔÏó³ÆÎªÔªËØ£¬¾³£Óõ½µÄÓÐVector¡¢Enumeration¡¢ArrayList¡¢Collection¡¢Iterator¡¢Set¡¢ListµÈ¼¯ºÏÀàºÍ½Ó¿Ú VECTORÀàÓëENUMERATION½Ó¿Ú
VECTORÀàÊÇJAVAÌṩµÄ´æ´¢½á¹¹£¬¿ÉÓÃÓÚ±£´æÒ»ÏµÁеĶÔÏó£¬ÓÉÓÚJAVA²»Ìṩ¶¯Ì¬Êý×飬VECTORÌṩÁËÒ»ÖÖÓ붯̬Êý×éÏà½üµÄ¹¦ÄÜ£¬Èç¹ûÒª½«Èç¸É¶ÔÏó±£´æµ½Ò»¸öÊý×éÖУ¬µ«Ô¤ÏȲ»ÖªµÀÒª±£´æµÄÊýĿʱ£¬VECTORÊÇÒ»ÖÖ²»´íµÄÑ¡Ôñ
±à³Ì£º½«¼üÅÌÉÏÊäÈëµÄÿλÊý×Ö±£´æµ½VECTORÖУ¬È»ºó½«¸÷λÊý×ÖÏà¼Ó
public class TestVector {
public static void main(String[] args) {
Vector v=new Vector();
System.out.println(\); while(true){ }
int sum=0;
Enumeration e=v.elements();//EnumerationÊÇÒ»¸ö½Ó¿ÚÀ࣬ËüÌṩÁË·ÃÎÊ
try{int b=System.in.read();//´Ó¼üÅ̶ÁÈëÊý¾Ý if(b=='\\r'||b=='\\n')//´¦Àí»Ø³µ»»ÐÐ break; else{
int number=b-'0';//ÒòΪÊäÈëµÄÔÚ»º´æÖÐÊÇASCIIÂ룬0µÄASCIIΪ48 v.addElement(new Integer(number));
}}catch(Exception e){}
ÖÚ¶àÊý¾Ý½á¹¹µÄ´æ´¢µÄËùÓÐÊý¾ÝµÄ³éÏó»úÖÆ£¬Í¨¹ýÕâÖÖ»úÖÆ¾Í¿ÉÒÔʹÓÃͬһÖз½Ê½£¬µ÷ÓÃͬÑùµÄ·½·¨Ãû·ÃÎʸ÷ÖÖÊý¾Ý½á¹¹Öд洢µÄËùÓÐÊý¾Ý£¬ÕâÖÖ»úÖÆ¾ÍÊÇÏÂÃæµÄÑ»· }
}
while(e.hasMoreElements()){//·µ»Øboolean£¬ÓÐÔªËØÎªtrue
Integer intObj=(Integer)e.nextElement();//È¡³öµ±Ç°¶ÔÏóOBJECT£¬
Òª½øÐÐת»»
sum+=intObj.intValue();//È¡³ö¶ÔÏóÖµÏà¼Ó }
System.out.println(sum);
×¢Òâ·½·¨Öж¨Òå±äÁ¿±ØÐ踳³õÖµ
Collection ½Ó¿ÚºÍIterator½Ó¿Ú
Collection½Ó¿ÚµÄʹÓÃÓëvectorÀàËÆ£¬µ«CollectionÖеĶÔÏóµÄ·ÃÎÊҪʹÓÃIterator½Ó¿Ú£¬IteratorµÄʹÓÃÓëEnumerationÏàËÆ£¬Õâ×éÍêÈ«¿ÉÒÔ´úÌæÉÏÃæµÄÄÇ×é
public class TestCollection {
public static void main(String[] args) {
// TODO Auto-generated method stub ArrayList v=new ArrayList();
System.out.println(\); while(true){
}
}
}
try{int b=System.in.read();//´Ó¼üÅ̶ÁÈëÊý¾Ý if(b=='\\r'||b=='\\n')//´¦Àí»Ø³µ»»ÐÐ break; else{
int number=b-'0';//ÒòΪÊäÈëµÄÔÚ»º´æÖÐÊÇASCIIÂ룬0µÄASCIIΪ48 v.add(new Integer(number));
}}catch(Exception e){}
int sum=0;
Iterator e=v.iterator();
while(e.hasNext()){//·µ»Øboolean£¬ÓÐÔªËØÎªtrue
Integer intObj=(Integer)e.next();//È¡³öµ±Ç°¶ÔÏó sum+=intObj.intValue();//È¡³ö¶ÔÏóÖµÏà¼Ó }
System.out.println(sum);
¿ÉÒÔ¿´³öVECTORºÍARRAYLIST·Ç³£ÏàËÆ£¬Ê²Ã´Çé¿öÏÂʹÓöþÕߣ¬VECTORÖÐËùÓз½·¨ÊÇÏß³Ìͬ²½µÄ£¬²¢·¢·ÃÎÊÊǰ²È«µÄ£¬¶øARRAYLISTÏß³ÌÊDz»Í¬²½µÄ£¬Èç¹ûҪͬ²½£¬ÔòÐèÒª³ÌÐòÔ±×Ô¼º¿ØÖÆ
Collection¡¢Set¡¢List½Ó¿ÚµÄÇø±ð£º
CollectionÊÇSetºÍList½Ó¿ÚµÄ¸¸À࣬ÊÇͨÓÃÐԵĽӿڣ¬Çø±ðÔÚÓÚ£¬
CollectionÖи÷¸öÔªËØÖ®¼äûÓÐÖ¸¶¨µÄ˳Ðò£¬¿ÉÒÔÓÐÖØ¸´ÔªËØ£¬¼´ÎÞ·¨½øÐÐÅÅÐò£¬Ã»ÓÐ˳Ðò£¬ÔÊÐíÓжà¸öNULL¶ÔÏó£»
SETÖеĸ÷¸öÔªËØ¶ÔÏóÖ®¼äûÓÐÖ¸¶¨Ë³Ðò£¬µ«²»ÔÊÐíÓÐÖØ¸´ÔªËØ£¬×î¶àÔÊÐíÓÐÒ»¸öNULL¶ÔÏó£»
LISTÖеĸ÷¸öÔªËØ¶ÔÏóÊÇÓÐÖ¸¶¨Ë³ÐòµÄ£¬ÔÊÐíÓÐÖØ¸´ÔªËغͶà¸öNULL¶ÔÏ󣬿ÉÒÔÓÃÓÚÅÅÐò ArrayListÒ²ÊÇʵÏÖÁËCollectionµÄÀà
import java.util.ArrayList; import java.util.Collections; public class Test_Array {
public static void main(String[] args) {
ArrayList al=new ArrayList(); al.add(new Integer(1)); al.add(new Integer(3)); al.add(new Integer(2));
System.out.println(al.toString());
Collections.sort(al);//ÅÅÐò£¬CollectionsËùÓз½·¨ÊǾ²Ì¬µÄ£¬ÓÃÓÚ²Ù×÷¼¯
ºÏÀà¶ÔÏ󣬱¾Éí²»ÊǼ¯ºÏÀà System.out.println(al.toString()); }
}
HashTableÀà
JAVAÌṩµÄÒ»Öָ߼¶Êý¾Ý½á¹¹£¬¿ÉÒÔÏñVECTORÒ»Ñù¶¯Ì¬´æ´¢Ò»ÏµÁеĶÔÏ󣬶øÇÒ¿ÉÒÔΪÿһ¸ö´æ´¢¶ÔÏ󣨳ÆÎªÖµ£©¶¼°²ÅÅÁíÍâÒ»¸ö¶ÔÏ󣨹ؼü×Ö£©ÓëÖ®Ïà¹Ø¡£Èç´æ´¢Èç¸ÉÖÐÓ¢ÎĹú¼ÒÃû¡£Ê¹Ó÷½·¨ÊÇ
Hashtable numbers=new Hashtable(); numbers.put(¡°0ne¡±,new Integer(1)); numbers.put(¡°0ne¡±,new Integer(2)); numbers.put(¡°0ne¡±,new Integer(3));
ʹÓÃPUT·½·¨½øÐд洢£¬½ÓÊչؼü×ÖºÍÖµÁ½¸ö¶ÔÏó£¬ÕâÁ½¸ö¶ÔÏó¶¼²»ÄÜÊÇNULL£¬Èç¹û´«µÝµÄ¹Ø¼ü×ÖÓëÔÀ´Ä³¸ö¹Ø¼ü×ÖÏàͬµÄ»°£¬¾ÍÓñ¾´Î´«µÝ¹ýÀ´µÄֵȥÐÞ¸ÄÔÀ´µÄ£¬¼´HASHTABLE²»ÄÜÓÐÖØ¸´µÄ¹Ø¼ü×Ö
¼ìË÷·½·¨ÓÃGET·½·¨£¬GET£¨¹Ø¼ü×Ö£© Integer n=(Integer)numbers.get(¡°two¡±);
ÓÃ×ö¹Ø¼ü×ÖµÄÀà±ØÐ踲¸ÇOBJECT.HASHCODEºÍOBJECT.EQUSLS·½·¨£¬Ê¹ÓÃequalsÀ´±È½ÏÁ½¸ö¹Ø¼ü×ÖÊÇ·ñÏàµÈ£¬¶øÇÒhashcodeµÄ·µ»ØÖµ±ØÐèÏàµÈ£¨²Å¿ÉÒÔ˵ÏàµÈ£©£¬Õâ¸öÖµÊǶÔÏóÔÚÄÚ´æÖеĵØÖ·ÒÔijÖÖ·½Ê½µÃµ½µÄ
±à³Ì£ºÊ¹ÓÃ×Ô¶¨ÒåµÄÀà×öHashtableÀà
public class Hashtable_key {
private String name=null; private int age=0;
Hashtable_key(String name,int age){//ǧÍò²»ÄÜÓзµ»ØÀàÐÍ this.name=name; }
public boolean equals(Object obj){
if(obj instanceof Hashtable_key){//ÅжÏÊDz»ÊÇÕâÖÖÀàÐ͵ĶÔÏó£¬ÊDzſÉ
Hashtable_key th=(Hashtable_key)obj; if(name.equals(th.name)&&age==th.age){ } else
return false; return true;
this.age=age;
ÒÔ±È½Ï }
}
}
else
return false;
public int hashCode(){
return name.hashCode()+age;//×¢ÒâStringbuffer²»ÄÜÓÃ×ö¹Ø¼ü×ÖÀà }
public String toString(){//¸²¸ÇĬÈϵÄtostring·½·¨£¬Ï£Íû·µ»ØÊÇÐÕÃûºÍÄêÁä return name+\+age; }
import java.util.Enumeration; import java.util.Hashtable; public class Test_Hashtable {
public static void main(String[]args){
Hashtable numbers=new Hashtable();
numbers.put(new Hashtable_key(\,15),new Integer(1));//numbers.put(new Hashtable_key(\,16),new Integer(2));//½øÐÐ
¹Ø¼ü×ֺ͹ØÁª¶ÔÏó
´æ´¢£¬½ÓÊչؼü×ÖºÍÖµÁ½¸ö¶ÔÏó
numbers.put(new Hashtable_key(\,17),new Integer(3));
Enumeration e=numbers.keys();//È¡³öHASTHTBLE¹Ø¼ü×Ö¼¯ºÏ£¬·µ»ØËùÓеÄwhile(e.hasMoreElements()){//È¡³öÿ¸ö¹Ø¼ü×Ö Hashtable_key hk=(Hashtable_key)e.nextElement();
System.out.print((hk+\));//ת»»³É×Ö·û´®´òÓ¡£¬hkÓÐÒ»¸öĬÈϵÄSystem.out.println(numbers.get(hk));//Óë¹Ø¼ü×Ö¶ÔÓÚµÄÖµ£¬Ö±½ÓÈ¡£¬
¹Ø¼ü×Ö
tostring·½·¨£¬Ç°Ãæ²»¸²¸ÇµÄ»°£¬¾Í²»ÊÇÏ£ÍûµÄ·µ»Ø ²»ÓñȽÏ
//×¢Òâ£¬Ç°ÃæµÄequalsºÍhashCode·½·¨ÊÇÓÉgetÀ´µ÷ÓÃµÄ }
System.out.println(numbers.get(new
//new Hashtable_key(\²úÉúµÄ¹Ø¼üÖµ¶ÔÏóÓëHASHTBLEÖд洢
Hashtable_key(\,15)));
µÄ¹Ø¼üÖµ¶ÔÏóÊÇÁ½¸öÍêÈ«²»Í¬µÄ¶ÔÏó£¬ÎÒÃÇ¿´À´ÊÇÏàµÈ£¬µ«³ÌÐò²»ÖªµÀ£¬ËùÒÔÎÒÃÇÒªÓ÷½·¨È¥¸²¸Ç£¬ÒòΪÕâÀïÉæ¼°µ½±È½Ï } }
15¡¢PropertiesÀà
ÊÇHASHBATBLµÄ×ÓÀ࣬½«ÆäÖеĹؼü×ÖºÍÖµ±£´æµ½ÎļþÖкʹÓÎļþÖжÁÈ¡¹Ø¼ü×ÖºÍÖµµ½HASHTABLE¶ÔÏóÖеķ½·¨
ÒªÓÃProperties.store£¨¹Ø¼ü×Ö£¬Öµ£©£¬¶¼ÒªÊÇStringÀàÐÍ ±à³Ì£º¼Ç¼³ÌÐòÔËÐÐij¸öÎļþ´ÎÊý£¬Ã¿´ÎÆô¶¯Ê±´òÓ¡´¦Àí
import java.io.FileInputStream; import java.io.FileOutputStream; import java.util.Properties; public class Properties_File {
public static void main(String[] args) {
Properties settings=new Properties(); try{
settings.load(new FileInputStream(\));//´ÓÎļþÖжÁÈ¡ÔË
ÐдÎÊý