]]>
]]>
java 娉涘瀷鐨勬畫閰風幇瀹炲氨鏄細
鍦ㄦ硾鍨嬩唬鐮佸唴閮紝鏃犳硶鑾峰緱浠諱綍鏈夊叧娉涘瀷鍙傛暟綾誨瀷鐨勪俊鎭?/span>
鍦ㄤ嬌鐢ㄦ硾鍨嬫椂錛屼換浣曞叿浣撶殑綾誨瀷閮借鎿﹂櫎錛屽敮涓鐭ラ亾鐨勬槸浣犲湪浣跨敤涓涓璞°傛瘮濡傦細List<String>鍜孡ist<Integer>鍦ㄨ繍琛屼簨瀹炰笂鏄浉鍚岀殑綾誨瀷銆備粬浠兘琚摝闄ゆ垚浠栦滑鐨?span style="line-height: 21px; color: #ff0000;">鍘熺敓綾誨瀷錛屽嵆List銆?/span>
snippet 1:
package com.cognizant.ch15;
import java.lang.reflect.Array;
import java.util.Arrays;
public class ArrayMaker<T> {
private Class<T> kind;
public ArrayMaker(Class<T> kind) {
this.kind = kind;
}
@SuppressWarnings("unckecked")
T[] create(int size) {
return (T[]) Array.newInstance(kind, size);
}
public static void main(String[] args) {
ArrayMaker<String> stringMaker = new ArrayMaker<String>(String.class);
String[] stringArray = stringMaker.create(10);
System.out.println(Arrays.toString(stringArray));
}
}
ouput:[null, null, null, null, null, null, null, null, null, null]
鐢變簬鎿﹂櫎錛宬ind瀹為檯涓婂皢琚瓨鍌ㄤ負浜咰lass錛岄潪String.calss銆傚湪鍒涘緩鏁扮粍鐨勬椂鍊欙紝Array.newInstance()瀹為檯涓婂茍娌℃湁鎷ユ湁kind鎵鍚殑綾誨瀷淇℃伅錛屽洜姝ゅ氨涓嶄細浜х敓鍏蜂綋鐨勭粨鏋溿?/p>
濡傛灉瑕佸垱寤轟竴涓鍣ㄨ屼笉鏄暟緇勶紝鎯呭喌鍗存湁鐐逛笉鍚岋細
snippet 2:
public class ListMaker<T>{
List<T> create(){
return new ArrayList<T>();
}
public static void main(String[] args){
ListMaker<String> stringMaker=new ListMaker<String>();
List<String> stringList=stringMaker.create();
}
}
鎿? 闄や嬌寰梒reate()鍐呴儴鐨刵ew ArrayList<T>涓殑<T>琚摝闄や簡錛屽湪榪愯鏃訛紝榪欎釜綾葷殑鍐呴儴娌℃湁浠諱綍<T>錛屼絾鏄張涓嶈兘鎶? ArrayList<T>鏀逛負ArrayList錛屽惁鍒欒櫧鐒剁紪璇戝櫒閫氳繃錛屼絾浼氱粰鍑鴻鍛娿?/p>
snippet 3:
package com.cognizant.ch15;
import java.util.ArrayList;
import java.util.List;
public class FilledListMaker<T> {
List<T> create(T t, int n) {
List<T> result = new ArrayList<T>();
for (int i = 0; i < n; i++) {
result.add(t);
}
return result;
}
public static void main(String[] args) {
FilledListMaker<String> stringMaker = new FilledListMaker<String>();
List<String> list = stringMaker.create("hello", 6);
System.out.println(list);
}
}
output:[hello, hello, hello, hello, hello, hello]
緙栬瘧鍣ㄦ棤娉曠煡閬撴湁鍏砪reate涓璗鐨勪換浣曚俊鎭紝浣嗘槸浠栦粛鐒跺彲浠ュ湪緙栬瘧鏈熺‘淇濇斁緗埌result涓璞″叿鏈塗綾誨瀷銆傚洜姝ゅ氨鏈変簡涓涓幇璞★細鍗充嬌鎿﹂櫎鍦ㄦ柟娉曟垨綾誨唴閮ㄧЩ闄や簡瀹為檯綾誨瀷鐨勪俊鎭紝緙栬瘧鍣ㄨ繕鏄彲浠ュ湪鏂規硶鎴栫被鐨勪嬌鐢ㄧ殑綾誨瀷鐨勫唴閮ㄤ竴鑷存с?/p>
閭ｄ箞灝辨湁涓涓棶棰橈細鎿﹂櫎鍚庣殑涓嶇煡閬撳張鍒扮煡閬撳叾鍏蜂綋綾誨瀷錛屼粬鏄繖涔堝仛鍒扮殑鍛紵
絳旀鏄細鎿﹂櫎鍦ㄦ柟娉曚綋涓Щ闄や簡綾誨瀷淇℃伅錛屾墍浠ュ湪榪愯鏃剁殑闂灝辨槸杈圭晫錛?span style="line-height: 21px;">鍗沖璞¤繘鍏ュ拰紱誨紑鏂規硶鐨勫湴鐐癸紝榪欐鏄紪璇戝櫒鍦ㄧ紪璇戞湡鎵ц綾誨瀷媯鏌ュ茍鎻掑叆杞瀷浠ｇ爜鐨勫湴鐐廣?/span>
娉涘瀷涓殑鎵鏈夊姩浣滈兘鍙戠敓鍦ㄨ竟鐣屽錛氬浼犻掕繘鏉ョ殑鍊艱繘琛岄澶栫殑緙栬瘧鏈熸鏌ワ紝騫舵彃鍏?瀵逛紶閫掑嚭鍘葷殑鍊肩殑杞瀷銆?/span>
鐢變簬涓嶇敤榪涜寮哄埗杞崲綾誨瀷浜嗭紝鎵浠ュ叿鏈夎緝楂樼殑瀹夊叏鎬у拰鏄撶敤鎬с備絾娉涘瀷鍏跺疄鍙槸鍦ㄧ紪璇戝櫒涓疄鐜扮殑鑰岃櫄鎷熸満騫朵笉璁よ瘑娉涘瀷綾婚」錛屾墍浠ヨ鍦ㄨ櫄鎷熸満涓皢娉涘瀷綾誨瀷榪涜鎿﹂櫎銆備篃灝辨槸璇達紝鍦ㄧ紪璇戦樁孌典嬌鐢ㄦ硾鍨嬶紝榪愯闃舵鍙栨秷娉涘瀷錛屽嵆鎿﹂櫎銆?/pre>榪欏鑷翠簡涓涓棶棰橈細鏃犳硶鍒涘緩娉涘瀷鏁扮粍銆?/span>Java鐨勬硾鍨嬪湪緙栬瘧鏃朵細鎿﹂櫎綾誨瀷淇℃伅銆侸ava涓殑鏁扮粍鏄氳繃鍙嶅皠鍔ㄦ佸緩绔嬬殑銆傛病鏈変簡綾誨瀷淇℃伅鎬庝箞鑳芥瀯閫犲嚭鏁扮粍銆?/span>
]]>
鍦╩ain涓? a => new StringBuffer("A"); b => new StringBuffer("B"); 鍦╰est.operater(a, b);榪欏彞錛屼紶鍏ョ殑鏄袱涓紩鐢? 鍦╫perater鏂規硶涓紝b琚噸鏂拌祴鍊間簡錛屽嵆寮曠敤鍦板潃鏀瑰彉浜? ================ 琛ュ厖涓涓嬶細java涓換浣曚竴涓璞″彉閲忓彧鏄寚鍚戝垱寤虹殑瀵硅薄鐨勪竴涓紩鐢? 渚嬪 String a = "KKK"; 閭ｄ箞 “KKK”鏄垱寤虹殑String瀵硅薄錛?a 鍒欐槸榪欎釜瀵硅薄鐨勫紩鐢紝鎴栬呰a淇濆瓨瀵硅薄“KKK”鍦ㄥ唴瀛樹腑鐨勫湴鍧
“==”涓?#8220;Equals”鍖哄埆
==鎿嶄綔姣旇緝鐨勬槸涓や釜鍙橀噺鐨勫兼槸鍚︾浉絳夛紝瀵逛簬寮曠敤鍨嬪彉閲忚〃紺虹殑鏄袱涓彉閲忓湪鍫嗕腑瀛樺偍鐨勫湴鍧鏄惁鐩稿悓錛屽嵆鏍堜腑鐨勫唴瀹規槸鍚︾浉鍚屻? equals鎿嶄綔琛ㄧず鐨勪袱涓彉閲忔槸鍚︽槸瀵瑰悓涓涓璞＄殑寮曠敤錛屽嵆鍫嗕腑鐨勫唴瀹規槸鍚︾浉鍚屻? ==姣旇緝鐨勬槸2涓璞＄殑鍦板潃錛岃宔quals姣旇緝鐨勬槸2涓璞＄殑鍐呭銆? 鏄劇劧錛屽綋equals涓簍rue鏃訛紝==涓嶄竴瀹氫負true錛?
]]>
杈撳嚭涓夎褰?br />
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List鏄湁搴忛泦鍚堬紝閲岃竟鐨勫璞℃湁鍏堝悗欏哄簭錛屽茍涓斿彲浠ラ噸澶嶏紙閲嶅鏄寚錛屽綋鍙栧緱鎸囧畾鐨勫璞℃椂錛屽悓涓涓被鐨勫璞″茍涓攅quals鏂規硶鐨勮繑鍥炲肩浉鍚屽嵆涓洪噸澶嶏級
Map涓瓨鏀劇殑閿煎璞＄殑寮曠敤錛屼絾鏄敭涓嶈兘閲嶅錛堥敭闆嗗嵆鏃犲簭闆嗗悎Set銆愬叿鏈塖et閲嶅鐨勭壒鎬с戯級
Set List 緇ф壙浜咰ollection鎺ュ彛錛屽彲浠ヤ嬌鐢–ollection瀹炵幇澶氭侊紝鑰孧ap娌℃湁銆?br />
]]>
public TestClass() {
System.out.println("wll");
}
public static void main(String[] args) {
TestClass tc=new TestClass();
}
}
緇ф壙鎺掑簭]]>
round 鍒欐槸4鑸?鍏ョ殑璁＄畻錛宺ound鏂規硶錛屽畠琛ㄧず“鍥涜垗浜斿叆”錛岀畻娉曚負Math.floor(x+0.5)錛屽嵆灝嗗師鏉ョ殑鏁板瓧鍔犱笂0.5鍚庡啀鍚戜笅鍙栨暣錛屾墍浠ワ紝Math.round(11.5)鐨勭粨鏋滀負12錛孧ath.round(-11.5)鐨勭粨鏋滀負-11銆?
Math.floor(1.4)=1.0
Math.round(1.4)=1
Math.ceil(1.4)=2.0
Math.floor(1.5)=1.0
Math.round(1.5)=2
Math.ceil(1.5)=2.0
Math.floor(1.6)=1.0
Math.round(1.6)=2
Math.ceil(1.6)=2.0
Math.floor(-1.4)=-2.0
Math.round(-1.4)=-1
Math.ceil(-1.4)=-1.0
Math.floor(-1.5)=-2.0
Math.round(-1.5)=-1
Math.ceil(-1.5)=-1.0
Math.floor(-1.6)=-2.0
Math.round(-1.6)=-2
Math.ceil(-1.6)=-1.0
]]>
String strss=null;
String [] str={"hello","world","janaury","february","thirsday","monday"};
for(int i=0;i<str.length;i++){
strss=str[i]+"/";
}
//String strs="nihao a he llo worl d dsa a d f a d";
String [] sr=strss.split("/");
for(int i=0;i<str.length;i++){
System.out.println(str[i]);
String strs="nihao a he llo worl d dsa a d f a d";
String [] str=strs.split("");
for(int i=0;i<str.length;i++){
System.out.println(str[i]);
}
String [] str=strs.split("");
for(int i=0;i<str.length;i++){
System.out.println(str[i]);
}
]]>
]]>