鍦ㄤ嬌鐢?Java Collections Framework 鏃訛紝蹇呴』鐭ラ亾 Collections 綾諱腑鐨勫彉閲忔槸鍝簺銆傝繖涓被鍖呭惈澶ч噺鏀寔闆嗗悎鎿嶄綔鐨勯潤鎬佹柟娉曘傚湪榪欓噷錛屾垜浠笉浼氬鎵鏈夋柟娉曡繘琛屼粙緇嶏紝鍥犱負鎮ㄥ彲浠ヨ嚜宸遍槄璇?API錛屼絾鏄垜浠皢浠嬬粛涓や釜緇忓父鍑虹幇鍦?Java 浠ｇ爜涓殑鏂規硶錛?
copy()sort()
絎竴涓柟娉曞厑璁稿皢涓涓泦鍚堢殑鍐呭澶嶅埗鍒板彟涓涓泦鍚堬紝濡備笅鎵紺猴細
List source = new ArrayList();
source.add("one");
source.add("two");
List target = new ArrayList();
target.add("three");
target.add("four");
Collections.copy(target, source);
System.out.println(target);
璇ヤ唬鐮佸皢 source 澶嶅埗鍒?target 涓傜洰鏍囦唬鐮佺殑澶у皬蹇呴』涓庢簮浠ｇ爜鐨勫ぇ灝忕浉鍚岋紝榪欐牱錛屽氨鏃犳硶灝?List 澶嶅埗鍒扮┖鐨?List 涓?/P>
sort() 鏂規硶鍏冪礌褰掔被鎴愬叾鑷劧欏哄簭銆傛墍鏈夊厓绱犻兘蹇呴』瀹炵幇 Comparable 鎺ュ彛錛岃繖鏍鳳紝瀹冧滑灝卞彲浠?I>鐩鎬簰姣旇緝銆傚儚 String 榪欐牱鐨勫唴緗被涔熷凡緇忓垱寤恒傚洜姝わ紝瀵逛簬涓緇勫瓧絎︿覆鑰岃█錛屽彲浠ヤ嬌鐢ㄤ互涓嬩唬鐮佹寜鐓у瓧鍏擱『搴忕殑鍗囧簭欏哄簭瀵瑰瓧絎︿覆榪涜鎺掑簭錛?/P>
List strings = new ArrayList();
strings.add("one");
strings.add("two");
strings.add("three");
strings.add("four");
Collections.sort(strings);
System.out.println(strings);
鎮ㄥ皢鍦ㄦ帶鍒跺彴涓幏寰?[four, one, three, two]銆備絾鏄幇鍦ㄥ彲浠ュ鍒涘緩鐨勭被榪涜鍒嗙被鍚楋紵鍙互瀵?Adult 榪涜鍒嗙被銆傞鍏堣璁╃被榪涜鐩鎬簰姣旇緝錛?/P>
public class Adult extends Person implements Comparable {
...
}
鐒跺悗瑕侀噸鍐?compareTo() 鏉ユ瘮杈冧袱涓?Adult 瀹炰緥銆傛垜浠皢淇濇寔鎴戜滑鐨勪緥瀛愬湪姣旇緝鏂歸潰鐨勭畝鍗曟э紝鎵浠ヨ渚嬩笉浼氳繘琛屽お澶氱殑姣旇緝鎿嶄綔錛?/P>
public int compareTo(Object other) {
final int LESS_THAN = -1;
final int EQUAL = 0;
final int GREATER_THAN = 1;
Adult otherAdult = (Adult) other;
if ( this == otherAdult ) return EQUAL;
int comparison = this.firstname.compareTo(otherAdult.firstname);
if (comparison != EQUAL) return comparison;
comparison = this.lastname.compareTo(otherAdult.lastname);
if (comparison != EQUAL) return comparison;
return EQUAL;
}
浠諱綍灝忎簬 0 鐨勬暟瀛楅兘鎰忓懗鐫鈥滃皬浜庘濓紝浣嗘槸 -1 鏄〃紺鴻繖涓剰鎬濅竴涓緢濂界敤鐨勫箋備笌姝ょ被浼鹼紝鐢?1 琛ㄧず鈥滃ぇ浜庘濅篃寰堟柟渚褲傛濡傛偍鍙互鐪嬪埌鐨勶紝0 鍒欐剰鍛崇潃鈥滅瓑浜庘濄備互榪欑鏂瑰紡姣旇緝涓や釜瀵硅薄鏄劇劧鏄竴涓墜鍔ㄨ繃紼嬨傛偍蹇呴』閬嶅巻瀹炰緥鍙橀噺騫舵瘮杈冩瘡涓彉閲忋傚湪榪欑鎯呭喌涓嬶紝鎴戜滑瑕佹瘮杈冨悕鍜屽錛屽茍鏍規嵁濮撴皬鏈夋晥鍦板浜轟滑榪涜鎺掑簭銆備絾鏄偍搴旇鑳藉鏄庣櫧涓轟粈涔堟垜浠殑渚嬪瓙榪囦簬綆鍗曘傛瘡涓?Adult 閮藉彧鏈変竴涓悕鍜屽銆傚鏋滄兂榪涜娣卞眰鐨勬瘮杈冿紝閭ｄ箞蹇呴』姣旇緝姣忎釜 Adult 鐨?Wallet錛屼互鏌ョ湅瀹冧滑鏄惁鐩哥瓑錛岃繖鍙兘鎰忓懗鐫鎴戜滑蹇呴』鍦?Wallet 鍜屽叾浣欏璞′笂瀹炵幇 compareTo()銆傛澶栵紝涓轟簡姝ｇ‘榪涜姣旇緝錛屾棤璁轟綍鏃墮噸鍐?compareTo()錛岄兘蹇呴』紜繚璇ユ瘮杈冧笌 equals() 鏄竴鑷寸殑銆傛垜浠病鏈夊疄鐜?equals()錛屾墍浠ヤ笉鐢ㄦ媴蹇冭涓庡畠涓鑷達紝浣嗘垜浠彲浠ュ仛鍒拌繖涓鐐廣備簨瀹炰笂錛屽湪榪斿洖 EQUAL 涔嬪墠錛屾垜宸茬粡鐪嬪埌鍖呭惈綾諱技浠ヤ笅浠ｇ爜琛岀殑浠ｇ爜錛?/P>
assert this.equals(otherAdult) : "compareTo inconsistent with equals.";
姣旇緝瀵硅薄鐨勫叾浠栨柟娉曟槸錛氭彁鍙?compareTo() 涓殑綆楁硶錛屽皢鍏舵斁鍏?Comparator 綾誨瀷鐨勫璞′腑錛岀劧鍚庡灝嗗垎綾葷殑闆嗗悎璋冪敤 Collections.sort() 鍜?Comparator錛屽涓嬫墍紺猴細
public class AdultComparator implements Comparator {
public int compare(Object object1, Object object2) {
final int LESS_THAN = -1;
final int EQUAL = 0;
final int GREATER_THAN = 1;
if ((object1 == null) ;amp;amp (object2 == null))
return EQUAL;
if (object1 == null)
return LESS_THAN;
if (object2 == null)
return GREATER_THAN;
Adult adult1 = (Adult) object1;
Adult adult2 = (Adult) object2;
if (adult1 == adult2)
return EQUAL;
int comparison = adult1.firstname.compareTo(adult2.firstname);
if (comparison != EQUAL)
return comparison;
comparison = adult1.lastname.compareTo(adult2.lastname);
if (comparison != EQUAL)
return comparison;
return EQUAL;
}
}
public class CommunityApplication {
public static void main(String[] args) {
Adult adult1 = new Adult();
adult1.setFirstname("Bob");
adult1.setLastname("Smith");
Adult adult2 = new Adult();
adult2.setFirstname("Al");
adult2.setLastname("Jones");
List adults = new ArrayList();
adults.add(adult1);
adults.add(adult2);
Collections.sort(adults, new AdultComparator());
System.out.println(adults);
}
}
鍦ㄦ帶鍒跺彴紿楀彛涓紝搴旇鐪嬪埌浠ユ煇縐嶉『搴忔帓鍒楃殑鈥淎l Jones鈥濆拰鈥淏ob Smith鈥濄?/P>
浣跨敤絎簩縐嶆柟娉曟槸鏈変竴浜涘ソ鐨勭悊鐢辯殑銆傛妧鏈柟闈㈢殑鐞嗙敱宸茬粡瓚呭嚭浜嗘湰鏂囩殑璁ㄨ鑼冨洿銆備笉榪囷紝浠庡ソ鐨?OOD 鐨勮搴︽潵鐪嬶紝灝嗘瘮杈冧唬鐮侀殧紱誨埌鍙︿竴涓璞′腑錛岃屼笉鏄負姣忎釜 Adult 鎻愪緵灝嗚嚜韜笌鍏朵粬瀵硅薄姣旇緝鐨勮兘鍔涙槸涓涓ソ涓繪剰銆傜劧鑰岋紝鍥犱負榪欐鏄?equals() 瑕佸仛鐨勪簨錛屾墍浠ュ嵆浣跨粨鏋滄槸甯冨皵鍊鹼紝瀵逛簬姣忕鏂規硶鑰岃█錛岄偅浜涗粛鐒舵槸涓浜涘ソ鍙傛暟銆?/P>
| 浣跨敤闆嗗悎 |
浣曟椂搴旇浣跨敤鐗規畩綾誨瀷鐨勯泦鍚堬紵榪欐槸涓涓敱鎮ㄥ仛鍑虹殑鍒ゆ柇鍐沖畾錛岃屼笖錛屾鏄洜涓鴻繖綾葷殑鍐沖畾錛屾偍甯屾湜鍍忎竴浣嶇紪紼嬩漢鍛橀偅鏍蜂粯鍑哄緢澶氥?/P>
灝界璁稿涓撲笟浜哄＋鐩鎬俊錛屾病鏈夊お澶氬叧浜庡湪浠諱竴緇欏畾鎯呭喌涓嬩嬌鐢ㄥ摢浜涚被鐨勭‖鎬ц瀹氥備互鎴戠殑涓漢緇忛獙鑰岃錛屽ぇ澶氭暟鏃墮棿閲岋紝鎴戜嬌鐢ㄩ泦鍚堛?CODE>ArrayList 鎴?HashMap錛堣璁頒綇錛?CODE>Map 涓嶆槸鐪熸鐨勯泦鍚堬級鑾峰緱浜嗘垚鍔熴傛偍鑷繁鍘諱綋楠屽彲鑳戒篃浼氭湁鍚屾牱鐨勬晥鏋溿備互涓嬫槸涓浜涚粡楠屾硶鍒欙紝鍏朵腑鐨勪竴浜涙樉鐒惰濂戒簬鍙﹀涓浜涳細
- 鍦ㄨ涓鴻嚜宸遍渶瑕佷竴涓泦鍚堟椂錛屼粠浣跨敤
List寮濮嬶紝鐒跺悗璁╀唬鐮佸憡璇夋偍鏄惁闇瑕佸彟涓縐嶇被鍨嬬殑闆嗗悎銆? - 濡傛灉闇瑕佹儫涓鐨勪竴緇勪粈涔堜笢瑗匡紝閭ｄ箞璇蜂嬌鐢?
Set銆? - 鍦ㄩ亶鍘嗛泦鍚堟椂錛屽鏋滆凱浠ｉ『搴忓緢閲嶈錛屽垯浣跨敤鍙敤鐨?
Tree...椋庢牸鐨勯泦鍚堛? - 閬垮厤浣跨敤
Vector錛岄櫎闈為渶瑕佸埄鐢ㄥ叾鍚屾鍔熻兘銆? - 鐩村埌錛堥櫎闈烇級鎬ц兘鍑虹幇闂錛屽惁鍒欎笉鐢ㄦ媴蹇冩渶浼樺寲銆?
闆嗗悎鏄?Java 璇█鐨勬渶寮哄ぇ鐨勪竴涓柟闈€備笉瑕佸鎬曚嬌鐢ㄩ泦鍚堬紝浣嗚鎻愰槻鈥滆漿鍚戔濄備緥濡傦紝浠ヤ笅鏄竴涓粠 Array 杞崲鍒?ArrayList 鐨勪竴涓究鍒╂柟娉曪細
Adult adult1 = new Adult();
Adult adult2 = new Adult();
Adult adult3 = new Adult();
List immutableList = Arrays.asList(new Object[] { adult1, adult2, adult3 });
theList.add(new Adult());
榪欎釜浠ｇ爜鎶涘嚭涓涓?UnsupportedOperationException錛屽洜涓虹敱 Arrays.asList() 榪斿洖鐨?List 鏄笉鍙彉鐨勩傝屾偍鍙堟棤娉曞皢鏂扮殑鍏冪礌娣誨姞鍒頒笉鍙彉鐨?List 涓紝鎵浠ュ繀欏葷暀蹇冧竴鐐廣?/STRONG>
import java.io.*;
public class execOP {
public execOP(){
//TODO
}
/**
* 鍩瘋澶栭儴鐨勭▼搴?鍙冩暩鐐烘暩緄?.榪斿洖紼嬪簭鐨勮幾鍑?涓嶅叿鏈夎幾鍏ョ殑鍔熻兘)
* @param appParam 紼嬪簭鍙婂弮鏁哥祫鎴愮殑鏁哥祫(姣忓嬪弮鏁哥偤涓鍊嬫暩緄勬垚鍝?
* @return
* @throws Exception
*/
public String execExternalApp(String []appParam) throws Exception{
String str="";
Process proc=Runtime.getRuntime().exec(appParam);
DataInputStream in = new DataInputStream(proc.getInputStream());
DataInputStream error = new DataInputStream(proc.getErrorStream());
try
{
String tmp="";
while ((tmp= in.readLine()) != null) {
str+="鎺у埗鍙拌幾鍑?"+tmp+"\n";
//System.out.println("鎺у埗鍙?鍑?"+tmp);
}
while ((tmp= error.readLine()) != null) {
str+="閷杓稿嚭:"+tmp+"\n";
//System.out.println("???鍑?"+tmp);
}
}
catch(Exception e)
{
System.out.println("鐛插彇鎳夌敤紼嬪簭杓稿嚭鏅傜櫦鐢烮O閷"+e.getMessage());
}
return str;
}
/**
* 鍩瘋澶栭儴鐨勭▼搴?鍙冩暩鐐哄瓧絎︿覆).榪斿洖紼嬪簭鐨勮幾鍑?涓嶅叿鏈夎幾鍏ョ殑鍔熻兘)
* @param appParam 紼嬪簭鍙婂弮鏁哥祫鎴愮殑鏁哥祫(姣忓嬪弮鏁哥偤涓鍊嬫暩緄勬垚鍝?
* @return
* @throws Exception
*/
public String execExternalApp(String appParam) throws Exception{
String str="";
Process proc = Runtime.getRuntime().exec(appParam);
DataInputStream in = new DataInputStream(proc.getInputStream());
DataInputStream error = new DataInputStream(proc.getErrorStream());
try{
String tmp="";
while ((tmp= in.readLine()) != null) {
str+="絀洪毣鍙拌幾鍑?"+tmp+"\n";
//System.out.println("鎺у埗鍙?鍑?"+tmp);
}
while ((tmp= error.readLine()) != null) {
str+="閷杓稿嚭:"+tmp+"\n";
//System.out.println("???鍑?"+tmp);
}
}
catch(Exception e){
System.out.println("鐛插彇鎳夌敤紼嬪簭杓稿嚭鏅傜櫦鐢烮O閷:"+e.getMessage());
}
return str;
}
/**
* 娓│紼嬪簭
* @param args
*/
public static void main(String[] args) {
execOP exec=new execOP();
String appcmd="\\\\IP\\c$\\Program Files\\WIPTracking\\XraySystem.exe";
//String appcmd=args[0];
try{
System.out.println(exec.execExternalApp(appcmd));
}
catch(Exception e){
}
}
}