java常用函数.doc

Java代码1. /*2. *根据传入的格式获取日期3. *4. *paramformat5. *如:YYYYMMDD|MM/dd/yyyy,hh:mm:ss6. *return字符串的日期7. */8. publicStringgetSysDate(Stringformat)9. StringdateStr=;10. try11. Formatformatter;12. Datedate=newDate();13. formatter=newSimpleDateFormat(format);14. dateStr=formatter.format(date);15. catch(Exceptione)16. System.out.println(e);17. 18. returndateStr;19. 20. /*21. *根据传入的格式获取日期22. *23. *paramformat24. *如:YYYYMMDD|MM/dd/yyyy,hh:mm:ss25. *return字符串的日期26. */27. publicStringgetFormatDate(Datedate,Stringformat)28. StringdateStr=;29. try30. Formatformatter;31. formatter=newSimpleDateFormat(format);32. dateStr=formatter.format(date);33. catch(Exceptione)34. System.out.println(e);35. 36. returndateStr;37. 38. /*39. *获取分割后的字符串数组信息40. *41. *paramStr42. *paramSplit43. *return字符串数组44. */45. publicStringgetSplit(StringStr,StringSplit)46. returnStr.split(Split);47. 48. /*49. *把字符串转换成指定的日期格式50. *51. *paramstr52. *paramformat53. *return54. */55. publicDateConvert(Stringstr,Stringformat)56. java.text.SimpleDateFormatsdf=newjava.text.SimpleDateFormat(format);57. try58. java.util.Dated=sdf.parse(str);59. returnd;60. catch(Exceptionex)61. ex.printStackTrace();62. returnnull;63. 64. 65. /*66. *获取月的天数67. *68. *paramyear69. *parammonth70. *return71. */72. publicstaticintgetdays(Stringyear,Stringmonth)73. intyearInt=Integer.parseInt(year);74. intmonthInt=Integer.parseInt(month);75. intmonthdays=31;76. switch(monthInt)77. case1:78. case3:79. case5:80. case7:81. case8:82. case10:83. case12:84. monthdays=31;85. break;86. 87. case2:88. if(isLeapyear(yearInt)89. monthdays=29;90. else91. monthdays=28;92. 93. break;94. 95. case4:96. case6:97. case9:98. case11:99. monthdays=30;100. break;101. 102. 103. returnmonthdays;104. 105. 106. /*107. *判断闰年108. *109. *paramyear110. *return111. */112. publicstaticbooleanisLeapyear(intyear)113. if(year%4=0&year%100!=0)|(year%400=0)114. returntrue;115. else116. returnfalse;117. 118. 119. 120. /*121. *判断某天是星期几122. *123. *paramstrDate124. *return0表示是星期天125. */126. publicstaticintgetWeekByDate(StringstrDate)127. intdayOfWeek=0;128. try129. 130. SimpleDateFormatsdf=newSimpleDateFormat(yyyy-MM-dd);131. Calendarcalendar=Calendar.getInstance();132. Datedate=newDate();133. date=sdf.parse(strDate);134. calendar.setTime(date);135. dayOfWeek=calendar.get(Calendar.DAY_OF_WEEK);136. catch(Exceptione)137. e.printStackTrace();138. 139. returndayOfWeek-1;140. 141. /*142. *判断字符串是不是数字143. *144. *paramstr145. *return146. */147. publicstaticbooleanisNumeric(Stringstr)148. Patternpattern=Ppile(0-9*);149. MatcherisNum=pattern.matcher(str);150. if(!isNum.matches()151. returnfalse;152. 153. returntrue;154. 155. /*156. *获得距给定日期countday的字符串格式157. *158. *paramdate159. *paramcountday160. *paramflag161. *为true表示日期前，为false表示日期后162. *returnYYYY-MM-DD163. */164. publicStringgetDateString(Datedate,intcountday,booleanflag)165. Stringdatestr=;166. if(flag)167. datestr=getFormatDate(newDate(newDate().getTime()-countday168. *24*60*60*1000l),yyyy-MM-dd);169. else170. datestr=getFormatDate(newDate(newDate().getTime()+countday171. *24*60*60*1000l),yyyy-MM-dd);172. 173. returndatestr;174. 175. /*176. *根据两个时间判断时间差177. *throwsParseException178. *throwsParseException179. */180. publicLonggetDateDifference(Datedate1,Datedate2)throwsParseException181. /Datedate1=newSimpleDateFormat(yyyy-mm-dd).parse(2008-3-31);182. /Datedate2=newSimpleDateFormat(yyyy-mm-dd).parse(2008-3-30);183. /日期相减得到相差的日期184. longday=(date1.getTime()-date2.getTime()/(24*60*60*1000)0?(date1185. .getTime()-date2.getTime()186. /(24*60*60*1000)187. :(date2.getTime()-date1.getTime()/(24*60*60*1000);188. returnday;189. 190. 191. /*192. *根据两个时间来判断时间的差值193. *paramdays194. *return195. */196. publicLonggetDateDifference1(Datedate1,Datedate2)throwsParseException197. /日期相减得到相差的日期198. longday=(date1.getTime()-date2.getTime()/(24*60*60*1000);199. returnday;200. 201. /*202. *返回当前时间的一个时间差时间203. *paramdays204. *return205. */206. publicstaticStringDs(intdays)207. SimpleDateFormatform=newSimpleDateFormat(yyyy-MM-dd);208. Calendarcalendar=Calendar.getInstance();209. intday=calendar.get(Calendar.DAY_OF_YEAR);210. calendar.set(Calendar.DAY_OF_YEAR,day-days);211. Datecc=calendar.getTime();212. returnform.format(cc);213. 214. /*215. *获取系统当前时间216. */217. publicstaticDategetSystemDate()218. SimpleDateFormatsf=newSimpleDateFormat(yyyy-MM-dd);219. Datedate=newDate();220. try221. returnnewSimpleDateFormat(yyyy-mm-dd).parse(sf.format(date);222. catch(ParseExceptione)223. 224. returnnull;225. 226. /*227. *判断是否为整数228. *229. *paramstr传入的字符串230. *return是整数返回true,否则返回false231. */232. publicstaticbooleanisInteger(Stringstr)233. Patternpattern=Ppile(-+?d*$);234. returnpattern.matcher(str).matches();235. 236. /*237. *判断是否为浮点数，包括double和float238. *239. *paramstr传入的字符串240. *return是浮点数返回true,否则返回false241. */242. publicstaticbooleanisDouble(Stringstr)243. Patternpattern=Ppile(-+?.d*$);244. returnpattern.matcher(str).matches();245. 246. /*247. *判断输入的字符串是否符合Email样式.248. *249. *paramstr传入的字符串250. *return是Email样式返回true,否则返回false251. */252. publicstaticbooleanisEmail(Stringstr)253. Patternpattern=Ppile(w+(-+.w+)*w+(-.w+)*.w+(-.w+)*$);254. returnpattern.matcher(str).matches();255. 256. /*257. *判断输入的字符串是否为纯汉字258. *259. *paramstr传入的字符窜260. *return如果是纯汉字返回true,否则返回false261. */262. publicstaticbooleanisChinese(Stringstr)263. Patternpattern=Ppile(u0391-uFFE5+$);264. returnpattern.matcher(str).matches();265. 266. 267. /*268. *是否为空白,包括null和269. *270. *paramstr271. *return272. */273. publicstaticbooleanisBlank(Stringstr)274. returnstr=null|str.trim().length()=0;275. 276. /*277. *判断是否为质数278. *279. *paramx280. *return281. */282. publicstaticbooleanisPrime(intx)283. if(x=7)284. if(x=2|x=3|x=5|x=7)285. returntrue;286. 287. intc=7;288. if(x%2=0)289. returnfalse;290. if(x%3=0)291. returnfalse;292. if(x%5=0)293. returnfalse;294. intend=(int)Math.sqrt(x);295. while(c=end)296. if(x%c=0)297. returnfalse;298. 299. c+=4;300. if(x%c=0)301. returnfalse;302. 303. c+=2;304. if(x%c=0)305. returnfalse;306. 307. c+=4;308. if(x%c=0)309. returnfalse;310. 311. c+=2;312. if(x%c=0)313. returnfalse;314. 315. c+=4;316. if(x%c=0)317. returnfalse;318. 319. c+=6;320. if(x%c=0)321. returnfalse;322. 323. c+=2;324. if(x%c=0)325. returnfalse;326. 327. c+=6;328. 329. returntrue;330. 331. /*332. *人民币转成大写333. *334. *paramvalue335. *returnString336. */337. publicstaticStringhangeToBig(doublevalue)338. 339. charhunit=拾,佰,仟;/段内位置表示340. charvunit=万,亿;/段名表示341. chardigit=零,壹,贰,叁,肆,伍,陆,柒,捌,玖;/数字表示342. longmidVal=(long)(value*100);/转化成整形343. StringvalStr=String.valueOf(midVal);/转化成字符串344. 345. Stringhead=valStr.substring(0,valStr.length()-2);/取整数部分346. Stringrail=valStr.substring(valStr.length()-2);/取小数部分347. 348. Stringprefix=;/整数部分转化的结果349. Stringsuffix=;/小数部分转化的结果350. /处理小数点后面的数351. if(rail.equals(00)352. /如果小数部分为0353. suffix=整;354. 355. else356. 357. suffix=digitrail.charAt(0)-0+角+digitrail.charAt(1)-0+分;/否则把角分转化出来358. 359. /处理小数点前面的数360. charchDig=head.toCharArray();/把整数部分转化成字符数组361. charzero=0;/标志0表示出现过0362. bytezeroSerNum=0;/连续出现0的次数363. for(inti=0;i0&zeroSerNum0)389. prefix+=hunitidx-1;390. if(idx=0&vidx0)391. 392. prefix+=vunitvidx-1;/段结束位置应该加上段名如万,亿393. 394. 395. 396. if(prefix.length()0)397. prefix+=圆;/如果整数部分存在,则有圆的字样398. returnprefix+suffix;/返回正确表示399. 400. /*401. *全角字符转半角字符402. *403. *paramQJStr404. *returnString405. */406. publicstaticfinalStringQJToBJChange(StringQJStr)407. 408. charchr=QJStr.toCharArray();409. Stringstr=;410. for(inti=0;ichr.length;i+)411. 412. chri=(char)(int)chri-65248);413. str+=chri;414. 415. returnstr;416. 417. /*418. *去掉字符串中重复的子字符串419. *420. *paramstr421. *returnString422. */423. privatestaticStringremoveSameString(Stringstr)424. 425. SetmLinkedSet=newLinkedHashSet();426. StringstrArray=str.split();427. StringBuffersb=newStringBuffer();428. 429. for(inti=0;istrArray.length;i+)430. 431. if(!mLinkedSet.contains(strArrayi)432. 433. mLinkedSet.add(strArrayi);434. sb.append(strArrayi+);435. 436. 437. System.out.println(mLinkedSet);438. returnsb.toString().substring(0,sb.toString().length()-1);439. 440. /*441. *根据指定方法的参数去构造一个新的对象的拷贝并将他返回442. *paramobj原始对象443. *return新对象444. *throwsNoSuchMethodException445. *throwsInvocationTargetException446. *throwsIllegalAccessException447. *throwsInstantiationException448. *throwsSecurityException449. *throwsIllegalArgumentException450. */451. SuppressWarnings(unchecked)452. publicstaticObjectcopy(Objectobj)throwsIllegalArgumentException,SecurityException,InstantiationException,IllegalAccessException,453. InvocationTargetException,NoSuchMethodException454. 455. /获得对象的类型456. ClassclassType=obj.getClass();457. 458. /通过默认构造方法去创建一个新的对象，getConstructor的视其参数决定调用哪个构造方法459. ObjectobjectCopy=classType.getConstructor(newClass).newInstance(newObject);460. 461. /获得对象的所有属性462. Fieldfields=classType.getDeclaredFields();463. 464. for(inti=0;ifields.length;i+)465. 466. /获取数组中对应的属性467. Fieldfield=fieldsi;468. 469. StringfieldName=field.getName();470. StringstringLetter=fieldName.substring(0,1).toUpperCase();471. 472. /获得相应属性的getXXX和setXXX方法名称473. StringgetName=get+stringLetter+fieldName.substring(1);474. StringsetName=set+stringLetter+fieldName.substring(1);475. 476. /获取相应的方法477. MethodgetMethod=classType.getMethod(getName,newClass);478. MethodsetMethod=classType.getMethod(setName,newClassfield.getType();479. 480. /调用源对象的getXXX（）方法481. Objectvalue=getMethod.invoke(obj,newObject);482. 483. /调用拷贝对象的setXXX（）方法484. setMethod.invoke(objectCopy,newObjectvalue);485. 486. 487. returnobjectCopy;488. 489. 490. /过滤特殊字符491. publicstaticStringencoding(Stringsrc)492. if(src=null)493. return;494. StringBuilderresult=newStringBuilder();495. if(src!=null)496. src=src.trim();497. for(intpos=0;possrc.length();pos+)498. switch(src.charAt(pos)499. case:result.append(");break;500. case:result.append(>);break;502. case:result.append(');break;503. case&:result.append(&);break;504. case%:result.append(&pc;);break;505. case_:result.append(&ul;);break;506. case#:result.append(&shap;);break;507. case?:result.append(&ques;);break;508. default:result.append(src.charAt(pos);break;509. 510. 511. 512. returnresult.toString();513. 514. /反过滤特殊字符515. publicstaticStringdecoding(Stringsrc)516. if(src=null)517. return;518. Stringresult=src;519. result=result.replace(",).replace(',);520. result=result.replace(<,);521. result=result.replace(&,&);522. result=re