java鏁版嵁綾誨瀷鐨勮漿鎹竴鑸垎涓夌,鍒嗗埆鏄?
(1). 綆鍗曟暟鎹被鍨嬩箣闂寸殑杞崲
(2). 瀛楃涓蹭笌鍏跺畠鏁版嵁綾誨瀷鐨勮漿鎹?
(3). 鍏跺畠瀹炵敤鏁版嵁綾誨瀷杞崲
涓嬮潰鎴戜滑瀵硅繖涓夌綾誨瀷杞崲鍒嗗埆榪涜璁鴻堪銆?br />2 綆鍗曟暟鎹被鍨嬩箣闂寸殑杞崲
鍦↗ava涓暣鍨嬨佸疄鍨嬨佸瓧絎﹀瀷琚涓虹畝鍗曟暟鎹被鍨嬶紝榪欎簺綾誨瀷鐢變綆綰у埌楂樼駭鍒嗗埆涓?br />[center](byte錛宻hort錛宑har)--int--long--float--double[/center]
綆鍗曟暟鎹被鍨嬩箣闂寸殑杞崲鍙堝彲浠ュ垎涓猴細(xì)
●浣庣駭鍒伴珮綰х殑鑷姩綾誨瀷杞崲
●楂樼駭鍒頒綆綰х殑寮哄埗綾誨瀷杞崲
●鍖呰綾昏繃娓＄被鍨嬭兘澶熻漿鎹?br />2.1鑷姩綾誨瀷杞崲
浣庣駭鍙橀噺鍙互鐩存帴杞崲涓洪珮綰у彉閲忥紝絎旇呯О涔嬩負(fù)鑷姩綾誨瀷杞崲,渚嬪錛屼笅闈㈢殑璇彞鍙互鍦↗ava涓洿鎺ラ氳繃錛?
byte b;int i=b;long l=b;float f=b;double d=b;
濡傛灉浣庣駭綾誨瀷涓篶har鍨嬶紝鍚戦珮綰х被鍨嬶紙鏁村瀷錛夎漿鎹㈡椂錛屼細(xì)杞崲涓哄搴擜SCII鐮佸鹼紝渚嬪\r
char c='c'; int i=c; System.out.println("output:"+i);
杈撳嚭錛歰utput:99;
瀵逛簬byte,short,char涓夌綾誨瀷鑰岃█錛屼粬浠槸騫崇駭鐨勶紝鍥犳涓嶈兘鐩鎬簰鑷姩杞崲錛屽彲浠ヤ嬌鐢ㄤ笅榪扮殑寮哄埗綾誨瀷杞崲銆?/p>
short i=99;char c=(char)i;System.out.println("output:"+c);
杈撳嚭錛歰utput:c;
浣嗘牴鎹瑪鑰呯殑緇忛獙錛宐yte,short,int涓夌綾誨瀷閮芥槸鏁村瀷錛屽洜姝ゅ鏋滄搷浣滄暣鍨嬫暟鎹椂錛屾渶濂界粺涓浣跨敤int鍨嬨?br />2.2寮哄埗綾誨瀷杞崲
灝嗛珮綰у彉閲忚漿鎹負(fù)浣庣駭鍙橀噺鏃訛紝鎯呭喌浼?xì)澶嶆潅涓浜涳紝浣犲彲浠ヤ嬌鐢ㄥ己鍒剁被鍨嬭漿鎹€傚嵆浣犲繀欏婚噰鐢ㄤ笅闈㈣繖縐嶈鍙ユ牸寮忥細(xì)
int i=99;byte b=(byte)i;char c=(char)i;float f=(float)i;
鍙互鎯寵薄錛岃繖縐嶈漿鎹㈣偗瀹氬彲鑳戒細(xì)瀵艱嚧婧㈠嚭鎴栫簿搴︾殑涓嬮檷錛屽洜姝ょ瑪鑰呭茍涓嶆帹鑽愪嬌鐢ㄨ繖縐嶈漿鎹€?br /> 2.3鍖呰綾昏繃娓＄被鍨嬭漿鎹?br /> 鍦ㄦ垜浠璁哄叾瀹冨彉閲忕被鍨嬩箣闂寸殑鐩鎬簰杞崲鏃訛紝鎴戜滑闇瑕佷簡瑙ｄ竴涓婮ava鐨勫寘瑁呯被錛屾墍璋撳寘瑁呯被錛屽氨鏄彲浠ョ洿鎺ュ皢綆鍗曠被鍨嬬殑鍙橀噺琛ㄧず涓轟竴涓被錛屽湪鎵ц鍙橀噺綾誨瀷鐨勭浉浜掕漿鎹㈡椂錛屾垜浠細(xì)澶ч噺浣跨敤榪欎簺鍖呰綾匯侸ava鍏辨湁鍏釜鍖呰綾伙紝鍒嗗埆鏄疊oolean銆丆haracter銆両nteger銆丩ong銆丗loat鍜孌ouble錛屼粠瀛楅潰涓婃垜浠氨鍙互鐪嬪嚭瀹冧滑鍒嗗埆瀵瑰簲浜?boolean銆乧har銆乮nt銆乴ong銆乫loat鍜宒ouble銆傝孲tring鍜孌ate鏈韓灝辨槸綾匯傛墍浠ヤ篃灝變笉瀛樺湪浠涔堝寘瑁呯被鐨勬蹇典簡銆?br /> 鍦ㄨ繘琛岀畝鍗曟暟鎹被鍨嬩箣闂寸殑杞崲錛堣嚜鍔ㄨ漿鎹㈡垨寮哄埗杞崲錛夋椂錛屾垜浠繪槸鍙互鍒╃敤鍖呰綾昏繘琛屼腑闂磋繃娓°?br /> 涓鑸儏鍐典笅錛屾垜浠鍏堝０鏄庝竴涓彉閲忥紝鐒跺悗鐢熸垚涓涓搴旂殑鍖呰綾伙紝灝卞彲浠ュ埄鐢ㄥ寘瑁呯被鐨勫悇縐嶆柟娉曡繘琛岀被鍨嬭漿鎹簡銆備緥濡傦細(xì)
渚?錛屽綋甯屾湜鎶奻loat鍨嬭漿鎹負(fù)double鍨嬫椂錛?/p>
float f1=100.00f; Float F1=new float(f1); Double d1=F1.doubleValue();//F1.doubleValue()涓篎loat綾葷殑榪斿洖double鍊煎瀷鐨勬柟娉?/p>
褰撳笇鏈涙妸double鍨嬭漿鎹負(fù)int鍨嬫椂錛?/p>
double d1=100.00; Double D1=new Double(d1); int i1=D1.intValue();
褰撳笇鏈涙妸int鍨嬭漿鎹負(fù)double鍨嬫椂錛岃嚜鍔ㄨ漿鎹細(xì)
int i1=200; double d1=i1;
綆鍗曠被鍨嬬殑鍙橀噺杞崲涓虹浉搴旂殑鍖呰綾伙紝鍙互鍒╃敤鍖呰綾葷殑鏋勯犲嚱鏁般傚嵆錛?br />Boolean(boolean value)銆丆haracter(char value)銆両nteger(int value)銆丩ong(long value)銆丗loat(float value)銆丏ouble(double value)
鑰屽湪鍚勪釜鍖呰綾諱腑錛屾繪湁褰負(fù)××Value()鐨勬柟娉曪紝鏉ュ緱鍒板叾瀵瑰簲鐨勭畝鍗曠被鍨嬫暟鎹傚埄鐢ㄨ繖縐嶆柟娉曪紝涔熷彲浠ュ疄鐜頒笉鍚屾暟鍊煎瀷鍙橀噺闂寸殑杞崲錛屼緥濡傦紝瀵逛簬涓涓弻綺懼害瀹炲瀷綾伙紝intValue()鍙互寰楀埌鍏跺搴旂殑鏁村瀷鍙橀噺錛岃宒oubleValue()鍙互寰楀埌鍏跺搴旂殑鍙岀簿搴﹀疄鍨嬪彉閲忋?br /> 3 瀛楃涓插瀷涓庡叾瀹冩暟鎹被鍨嬬殑杞崲
閫氳繃鏌ラ槄綾誨簱涓悇涓被鎻愪緵鐨勬垚鍛樻柟娉曞彲浠ョ湅鍒幫紝鍑犱箮浠巎ava.lang.Object綾繪淳鐢熺殑鎵鏈夌被鎻愪緵浜唗oString()鏂規(guī)硶錛屽嵆灝嗚綾昏漿鎹負(fù)瀛楃涓層備緥濡傦細(xì)Characrer,Integer,Float,Double,Boolean,Short絳夌被鐨則oString()鏂規(guī)硶toString()鏂規(guī)硶鐢ㄤ簬灝嗗瓧絎︺佹暣鏁般佹誕鐐規(guī)暟銆佸弻綺懼害鏁般侀昏緫鏁般佺煭鏁村瀷絳夌被杞崲涓哄瓧絎︿覆銆傚涓嬫墍紺猴細(xì)
int i1=10;float f1=3.14f;double d1=3.1415926;Integer I1=new Integer(i1);//鐢熸垚Integer綾籠rFloat F1=new Float(f1); //鐢熸垚Float綾籠rDouble D1=new Double(d1); //鐢熸垚Double綾籠r//鍒嗗埆璋冪敤鍖呰綾葷殑toString()鏂規(guī)硶杞崲涓哄瓧絎︿覆String si1=I1.toString();String sf1=F1.toString();String sd1=D1.toString();Sysytem.out.println("si1"+si1);Sysytem.out.println("sf1"+sf1);Sysytem.out.println("sd1"+sd1);
浜斻佸皢瀛楃鍨嬬洿鎺ュ仛涓烘暟鍊艱漿鎹負(fù)鍏跺畠鏁版嵁綾誨瀷
灝嗗瓧絎﹀瀷鍙橀噺杞崲涓烘暟鍊煎瀷鍙橀噺瀹為檯涓婃湁涓ょ瀵瑰簲鍏崇郴錛屽湪鎴戜滑鍦ㄧ涓閮ㄥ垎鎵璇寸殑閭ｇ杞崲涓紝瀹為檯涓婃槸灝嗗叾杞崲鎴愬搴旂殑ASCII鐮侊紝浣嗘槸鎴戜滑鏈夋椂榪橀渶瑕佸彟涓縐嶈漿鎹㈠叧緋伙紝渚嬪錛?1'灝辨槸鎸囩殑鏁板?錛岃屼笉鏄叾ASCII鐮侊紝瀵逛簬榪欑杞崲錛屾垜浠彲浠ヤ嬌鐢–haracter鐨刧etNumericValue(char ch)鏂規(guī)硶銆?br />鍏丏ate綾諱笌鍏跺畠鏁版嵁綾誨瀷鐨勭浉浜掕漿鎹?br /> 鏁村瀷鍜孌ate綾諱箣闂村茍涓嶅瓨鍦ㄧ洿鎺ョ殑瀵瑰簲鍏崇郴錛屽彧鏄綘鍙互浣跨敤int鍨嬩負(fù)鍒嗗埆琛ㄧず騫淬佹湀銆佹棩銆佹椂銆佸垎銆佺錛岃繖鏍峰氨鍦ㄤ袱鑰呬箣闂村緩绔嬩簡涓涓搴斿叧緋伙紝鍦ㄤ綔榪欑杞崲鏃訛紝浣犲彲浠ヤ嬌鐢―ate綾繪瀯閫犲嚱鏁扮殑涓夌褰㈠紡錛?br />Date(int year, int month, int date)錛氫互int鍨嬭〃紺哄勾銆佹湀銆佹棩
Date(int year, int month, int date, int hrs, int min)錛氫互int鍨嬭〃紺哄勾銆佹湀銆佹棩銆佹椂銆佸垎
Date(int year, int month, int date, int hrs, int min, int sec)錛氫互int鍨嬭〃紺哄勾銆佹湀銆佹棩銆佹椂銆佸垎銆佺\r
鍦ㄩ暱鏁村瀷鍜孌ate綾諱箣闂存湁涓涓緢鏈夎叮鐨勫搴斿叧緋伙紝灝辨槸灝嗕竴涓椂闂磋〃紺轟負(fù)璺濈鏍兼灄灝兼不鏍囧噯鏃墮棿1970騫?鏈?鏃?鏃?鍒?縐掔殑姣鏁般傚浜庤繖縐嶅搴斿叧緋伙紝Date綾諱篃鏈夊叾鐩稿簲鐨勬瀯閫犲嚱鏁幫細(xì)Date(long date)
鑾峰彇Date綾諱腑鐨勫勾銆佹湀銆佹棩銆佹椂銆佸垎銆佺浠ュ強鏄熸湡浣犲彲浠ヤ嬌鐢―ate綾葷殑getYear()銆乬etMonth()銆乬etDate()銆乬etHours()銆乬etMinutes()銆乬etSeconds()銆乬etDay()鏂規(guī)硶錛屼綘涔熷彲浠ュ皢鍏剁悊瑙ｄ負(fù)灝咲ate綾昏漿鎹㈡垚int銆?br />鑰孌ate綾葷殑getTime()鏂規(guī)硶鍙互寰楀埌鎴戜滑鍓嶉潰鎵璇寸殑涓涓椂闂村搴旂殑闀挎暣鍨嬫暟錛屼笌鍖呰綾諱竴鏍鳳紝Date綾諱篃鏈変竴涓猼oString()鏂規(guī)硶鍙互灝嗗叾杞崲涓篠tring綾匯?br />鏈夋椂鎴戜滑甯屾湜寰楀埌Date鐨勭壒瀹氭牸寮忥紝渚嬪20020324錛屾垜浠彲浠ヤ嬌鐢ㄤ互涓嬫柟娉曪紝棣栧厛鍦ㄦ枃浠跺紑濮嬪紩鍏ワ紝
import java.text.SimpleDateFormat;import java.util.*;java.util.Date date = new java.util.Date();//濡傛灉甯屾湜寰楀埌YYYYMMDD鐨勬牸寮廠impleDateFormat sy1=new SimpleDateFormat("yyyyMMDD");String dateFormat=sy1.format(date);//濡傛灉甯屾湜鍒嗗紑寰楀埌騫達(dá)紝鏈堬紝鏃impleDateFormat sy=new SimpleDateFormat("yyyy");SimpleDateFormat sm=new SimpleDateFormat("MM");SimpleDateFormat sd=new SimpleDateFormat("dd");String syear=sy.format(date);String smon=sm.format(date);String sday=sd.format(date);
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