JAVA面试题大全

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12ETresetᫀ(1)publicstaticString[]splitStringByComma(Stringsource))if(source==nullllsource.trim().equals(,H'))returnnull;StringTokenizercommaToker=newStringTokenizer(source,",H);String[Jresult=newString[commaToker.countTokens()J;inti=0;while(commaToker.hasMoreTokens()){result[ij=commaToker.nextToken();i++W

13returnresult;)YZ[ᔊStringᦪ]Integer.parseInt(Strings)^ᡂint`]ᡂintᦪ]Arrays.sort(int[]a),aᦪ]ᓣBABab8c2d2.efgᣚijkᦪ5ḄefgᣚᡂlmnḄop᝞:#¥1011
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143ஹ()%᎛Ḅ᡻z{B|⚪}⌱=⚪|~ᡭᓺdNO?:᱄:packagetest;publicclassFatherClasspublicFatherClass()System.out.println(nFatherClassCreate");:

15packagetest;importtest.FatherClass;publicclassChildClassextendsFatherClasspublicChildClass()System.out.println(MChildClassCreate");publicstaticvoidmain(String[]args)FatherClassfc=newFatherClass();

16ChildClasscc=newChildClassQ;2dPQ:C:>javatest.ChildClassFatherClassCreateFatherClassCreateChildClassCreate4ஹᑁḄp?Mṹ᝞:

17packagetest;publicclassOuterClassprivateclassInterClasspublicInterClassQSystem.out.printlnC'InterClassCreate'*);))publicOuterClass()

18InterClassic=newInterClass();System.out.println("OuterClassCreate");)publicstaticvoidmain(String[Jargs)OuterClassoc=newOuterClassQ;))2dPQ:C:>javatest/OuterClass

19InterClassCreateOuterClassCreate⚪:publicclassOuterClass{privatedoubled1=1.0;//insertcodehere)Youneedtoinsertaninnerclassdeclarationatline3.Whichtwoinnerclassdeclarationsarevalid?(Choosetwo.)A.classInnerOne{

20publicstaticdoublemethoda(){returndl;}B.publicclassInnerOne{staticdoublemethoda(){returndl;}C.privateclassInnerOne{doublemethoda(){returndl;}D.staticclassInnerOne{protecteddoublemethoda(){returndl;}

21E.abstractclassInnerOne{publicabstractdoublemethoda();᝞:.☟᝱ᑁᨵ☟᝱ᡂᕒ☟᝱ᑁᑣ+ᨵ☟᝱ᡂᕒ஺ᦑAஹB┯.☟᝱ᑁḄ☟᝱ᡂᕒ|᜜Ḅ☟᝱^|᜜Ḅ☟᝱^;returnd1d┯஺ᦑD┯.☟᝱ᑁḄ☟᝱ᡂᕒ|᜜Ḅ☟᝱^஺ᦑC.ᫀRCஹE

225ஹJavaḄ¡-.-.⚪#ᡈ|ᵨJAVASOCKET-.¢£¤ᘤ¦5§ᑏᐭ©ᙢLM:Server«.B:packagetest;importjava.net.*;importjava.io.*;publicclassServerprivateServerSocketss;privateSocketsocket;privateBufferedReaderin;privatePrintWriterout;

23publicServer()ss=newServerSocket(1OOOO);while(true)socket=ss.accept();StringRemotelP=socket.getInetAddress().getHostAddress();StringRemotePort=":n+socket.getLocalPort();System.out.println(HAclientcomein!IP:n+RemoteIP+RemotePort);

24in=newBufferedReader(newInputStreamReader(socket.getInputStream()));Stringline=in.readLine();System.out.println(uCleintsendis+line);out=newPrintWriter(socket.getOutputStream(),true);out.println(nYourMessageReceived!'*);out.close();in.close();socket.close();

25}catch(lOExceptione)out.println("wrong");publicstaticvoidmain(String[]args)newServer();
Client«.B:

26packagetest;importjava.io.*;importjava.net.*;publicclassClientSocketsocket;BufferedReaderin;PrintWriterout;publicClientQ

27trySystem.oul.println(,'TrytoConnectto127.0.0.l:10000n);socket=newSocket(n127.0.0.1",10000);System.out.println("TheServerConnected!");System.out.println("PleaseentersomeCharacter:0);BufferedReaderline=newBufferedReader(newInputStreamReader(System.in));out=newPrintWriter(socket.getOutputStream(),true);out.println(line.readLine());

28in=newBufferedReader(newInputStreamReader(socket.getInputStream()));System.out.println(in.readLine());out.close();in.close();socket.close();}catch(IOExceptione)out.println(uWrong");publicstaticvoidmain(String[]args)

29newClient();
6ஹᵨJAVAᑭ᣸BJAVABᑡᓄḄ¯#°?᝞ᙠCOLLECTION᪾¶,±²⌕NO᪵Ḅ:ᵨ·ᐭ¯¸z᣸Bṹ᝞packagetest;importjava.util.*;classInsertSortArrayListal;

30publicInsertSort(intnum,inimod)al=newArrayList(num);Randomrand=newRandom();System.out.println(nTheArrayListSortBefore:'1);for(inti=0;i

31publicvoidSortlt()Integertemplnt;iniMaxSize=l;for(inti=l;i=((Integer)al.get(MaxSize-l)).intValue())al.add(MaxSize,templnt);MaxSize++;

32System.out.println(al.toStringO);}else{for(intj=O;j=tempInt.intValue())al.add(j,templnt);MaxSize++;System.out.println(al.toStringO);

33break;System.out.println(MTheArrayListSortAfter:");for(inti=O;i

34publicstaticvoidmain(String[]args)InsertSortis=newInsertSort(10,100);is.SortIt();JAVABᓄḄ¯java.io.SerializableCollection᪾¶±²⌕Comparable¹Comparator7ஹ-.-ᑏº»5§¼Ḅ½ᦪ2ᐭR5§¼¹5⁚ᦪ2dRᢥ5⁚º»Ḅ5§¼஺⌕¿ÀÁ5ºÃ᝞“ᡃABC”4,ÆǺR“ᡃAB”2ᐭ“ᡃABCÁDEF”6,ÆÇ2dR“ᡃABC”“ᡃABC+ÁḄÔ஺ṹ᝞:packagetest;

35classSplitStringStringSplitStr;intSplitByte;publicSplitString(Stringstr,intbytes)SplitStr=str;SplitByte=bytes;System.out.println(nTheStringis:',,+SplitStr+Hz;SplitBytes=n+SplitByte);

36publicvoidSplitlt()intloopCount;loopCount=(SplitStr.length()%SplitByte==0)?(SpIitStr.lenglh()/SplitByte):(SplitStr.length()/SplitByte+1);System.out.println("WillSplitinton+loopCount);for(inti=1;i<=loopCount;i++)if(i==loopCount){System.out.println(SplitStr.substring((i-l)icSplitByte,SplitStr.length()));}else{

37System.out.println(SplitStr.substring((i-l)*SplitByte,(i:1:SplitByte)));)))publicstaticvoidmain(String[Jargs)SplitStringss=newSplitStringC'testddᦻdsafᵱᜧ3443nl43lÌ0ewldfls=103H,4);ss.SplitIt();

388ஹJAVA&Í.-.஺ᵨJAVAᑏ&Í..B᝞ᑏÍ.Î1,Ï^Ð2d஺ÑÒᜧÓ⊡ÕÖÖ9,STRING
STRINGBUFFERḄ×Ø஺STRINGḄÙÚ^ḄSTRINGBUFFERḄÙÚ^Ḅ஺᝞Q~Ï5§¼ḄᑁÛÜݸzÞßᱯØᑁÛ⌕áᦋ%ãOäᵨStringBuffer,᝞Qᨬ;◤⌕String,ãOäᵨStringBufferḄtoString()¯Jsp☢1ஹjspᨵçèᑁéÏ?ßᵨᑖØNO?:JSPᐳᨵ9°ë©ᑁé]ì(
ASPḄ6°ᑁ]ìíÏÆ):requestᵨᡝ«ðñòðñᒹôᩭGET/POSTðñḄöᦪresponse÷⚓møᵨᡝ«ḄøÆpageContext÷⚓Ḅùឋᙠûüýᳮ

39session
ðñᨵᐵḄ
applicationservletᙠ᡻Ḅᑁoutᵨᩭ〈ḄconfigservletḄ᪀pageJSP⚓exception┐┯⚓ᣓᣍḄ"᜜2ஹjspᨵ&'()?)ᵨᑖ,-./01:JSPᐳᨵ45667()jsp:include8ᙠ⚓☢:;<Ḅ=᎛?ᐭ-BCᦻ஺jsp:useBean8FGᡈὅJ"ᓄBCJavaBean஺jsp:setProperty8LMJavaBeanḄOឋ஺

40jsp:getProperty8QCJavaBeanḄOឋ஺jsp:forward8R;ij-
klᡠnᦻcḄoᓄ〉ᔠᵨrᒹn(᝱⚓☢tuv4wxᦪ☟᝱INCLUDEᵨincludezṹJh|}
klᡠnᦻḄoᓄ〉ᵨrᒹn☟᝱⚓☢<%@includefile="included.htmu%>4ஹ~6Sᑖ,-./?ᨵ./g,?18ᨵ~6ᑖ,]:

41ὅ⚓☢}
SᔣincludeᡠᢣḄ⚓☢-⚓Ḅ⚓☢-ᩭḄ⚓☢஺᡻
ᩭrᦪᵨ஺tuv4wxᦪ.ὅᐰSᔣU⚓☢}
ᩭ஺rgoto஺Servlet☢1BServletḄ_ᕜ?1:servletᨵḄ_Ḅ|ᒹ¡¢£J"ᓄஹ¤¥ᓄஹᜐᳮ;<4¨©ª«஺¬C_ᵫjavax.servlet.Servlet®¯Ḅinit,service£destroy°⊤²஺2ஹServlet᱐´µ¶·¸Ḅ-&~C᱐·¹Ḅ}º?»¼ᜧ¾⊡ÀÁÁ3ஹJAVASERVLETAPIcforward஺eredirect஺ḄgÂlj?1:ὅÃ-ᘤcÄᑴᩗḄSᔣᙠÇᡝÉXYᘤᙢᙬÌc}
SᔣḄᙢᙬÍὅᑣ-ᐰḄSXYᘤÏ
ÐᑮSḄᙢᙬtÑUÒ〈;<Ó®஺¬᪵ÕXYᘤḄᙢᙬÌcv4ÖᑮSḄÓ®ᙢᙬ஺ᡠ4ὅסØᦔᙠὅv4ÚÛ◤⌕=Þßàᵨforward஺°tu¬᪵áᨵâr◚äJ▭ḄÓ®஺ᙠᨵ'æç5è᝞◤⌕SᑮBCᐸi©ªᘤÀḄëìᑣíîàᵨsendRedirect஺°஺

424ஹServletḄ7᪀publicclassServIetNameextendsHttpServlet{publicvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse)throwsServletException,lOException{)publicvoiddoGet(HttpServletRequestrequest,HttpServletResponseresponse)throwsServletException,lOException{))JdbcஹJdo☢

431ஹvï
ðñᑏBóJdbcôOracleḄõötJhᦪWl÷.1:õö᝞5:packagehello.ant;importjava.sql.*;publicclassjdbcStringdbUrl=Mjdbc:oracle:thin:@127.0.0.1:1521:orcln;StringtheUser=uadminn;StringthePw=nmanagern;Connectionc=null;Statementconn;

44ResultSetrs=null;publicjdbc()try{Class.forName("oracle.jdbc.driver.OracleDrivern).newInstance();c=DriverManager.getConnection(dbUrl,theUser,thePw);conn=c.createStatement();}catch(Exceptione){e.printStackTraceQ;

45publicbooleanexecuteUpdate(Stringsql)conn.executeUpdate(sql);returntrue;catch(SQLExceptione)e.printStackTrace();returnfalse;

46publicResultSetexecuteQuery(Stringsql)rs=null;tryrs=conn.executeQuery(sql);catch(SQLExceptione)

47e.printStackTraceQ;returnrs;publicvoidclose()tryconn.close();c.close();

48catch(Exceptione)e.printStackTrace();publicstaticvoidmain(String[]args)ResultSetrs;jdbcconn=newjdbc();rs=conn.executeQuery(nselect*fromtest");try(

49while(rs.next())System.out.println(rs.getString(,'id,'));System.out.println(rs.getString(^^name'^));}catch(Exceptione)e.printStackTrace();

502ஹClass.forNameḄ)ᵨ0]./⌕ᵨ018ᵨø¸ùBC4úûüᢣ|[ýḄ[Ḅþ.3ஹJdo-./?1:JDO-JavaþᢝᓄḄḄjavadataobjectḄᵨᦪḄḄ᪗ᓄAPI஺JDO!"Ḅ#$%&'(ᕒᩭ+#ᦪ,ᐰ.◤⌕1᜜Ḅ3ṹ5᝞JDBCAPIḄ7ᵨ8஺9:;ᳲḄ=>?@ABCDᑮJDOFGᖪIJ7&'(ᕒKῃMᩭNOPQRSTUᙠWXYZJ஺[᜜JDO\ᮣ^$_`aᙠbcᦪdeJf>.JDBCi☢ᔣᐵmᦪ5RDBMS
JDOnoᵨᑮbcᦪdeḄ#pqr᝞ᐵmᦪஹᦻuஹXMLavᦪODBMS
ww7xyᵨ`Dzឋn|஺4ஹᙠORACLEᜧᦪ~Ḅᑖ⚓K஺•ᵨIDᨵeᝅ஺ᑖ⚓<%inti=l;intnumPages=14;

51Stringpages=request.getParameter("page");intcurrentPage=1;currentPage=(pages==null)?(1):{Integer.parselnt(pages)}sql="selectcount(*)fromtables'1;ResultSetrs=DBLink.executeQuery(sql);while(rs.next())i=rs.getlnt(1);intintPageCount=l;intPageCount=(i%numPages==0)?(i/numPages):(i/numPages+l);intnextPage;intupPage;nextPage=currentPage+1;

52if(nextPage>=intPageCount)nextPage=intPageCount;upPage=currentPage-1;if(upPage<=l)upPage=l;rs.close();sql=uselect*fromtables";rs=DBLink.executeQuery(sql);i=0;while((i஻Mᑁ஻M⚓

53n"v|:<%=currentPage%>/<%=intPageCount%xahref=nList.jsp?page=l',>^-^^n>_h⚓<%for(intj=l;j<=intPageCount;j++){if(currentPage!=j){%>">[<%=j%>]<%}else{out.printing);

54%>">⚓">ᨬ⚓Xml☢1ஹxmlᨵ:K᪆ᢈ?¡¢£¤:ᨵDOM,SAX,STAXwDOM:ᜐᳮᜧ¨ᦻuQᐸឋqªḄ«¬ᔍ®஺9¯⚪ᵫDOMḄ᪛³᪀ᡠ⌼ᡂḄ9³᪀ᓰᵨḄᑁ¹ºO»DOM¼½ᙠK᪆ᦻu¾¿À᦮ᦻ᫏Ãᐭᑁ〉ᔠXMLḄÇÈɯSAX:.ÊDOM,SAXËuÌͨḄXMLK᪆Î஺_ÏÐÑXMLᦻu.◤⌕—ÓᐰÔÃÕ᦮ᦻu஺Ö⍗ᑮØᦻu&ᜮᦻ᫏³Úᡈὅ᪗Ý&ᜮÞ᪗ݳÚQ_ßà'ËuᵨᡝoâᙠᐸãäËuᑏᐭᜐᳮ3ṹᩭᜐᳮXMLᦻu〉ᔠXMLḄÏÐɯ

55STAX:StreamingAPIforXML(StAX)2ஹæᙠ⚗èᵨᑮxmlᢈḄ:☢?᝞céÊḄ?:ᵨᑮᦪêëìíîï☢஺ᙠðᦪñᣚóôQõ.qᦪöḄᦪ÷ÃᡂXMLᦻuᯠõXMLᦻuùúᡭᒹýþoâÿ
〈ᦈὅᦈXMLᦻᐵᜐᳮ஺ᙠ!"#ᑭᵨXML&'()*ḄḄᔜ-!".ᦪ012ᙠXMLᦻ஺3ஹᵨjdom᪆xmlᦻ#᝞67ᦻ8⚪?᝞6᪆?;:=᝞>?ṹ,ᵨBṹ)CD'7packagetest;importjava.io.*;publicclassDOMTestprivateStringinFile="c:\people.xml”;privateStringoutFile="c:\peop1e.xml”;

56publicstaticvoidmain(Stringargs[])newDOMTest();)publicDOMTest()tryjavax.xml.parsers.DocumentBuilderbuilder=javax.xml.parsers.DocumentBuilderFactory.newInstance().newDocumentBuilder();org.w3c.dom.Documentdoc=builder.newDocument();

57org.w3c.dom.Elementroot=doc.createElement("ὁH");org.w3c.dom.Elementwang=doc.crealeEIement(“L”);org.w3c.dom.Elementliu=doc.createElement("ᦻN);wang.appendChild(doc.createTextNode("ᡃPLὁH”));root.appendChild(wang);doc.appendChild(root);javax.xml.transform.Transformertransformer=javax.xml.transform.TransformerFactory.newInstance().newTransformer();transformer.setOutputProperty(javax.xml.transform.OutputKeys.ENCODING,"gb2312”);transformer.setOutputProperty(javax.xml.transform.OutputKeys.INDENT,^yes11);

58transformer.transform(newjavax.xml.transform.dom.DOMSource(doc),newjavax.xml.transform.stream.StreamResult(outFile));catch(Exceptione)System.out.println(e.getMessage());

594ஹBQᵨJAVA᪆XMLḄ)C.;:ᵨSAX)C᪆XML,XMLᦻ᝞>:LTVv/name>(collegeுX▾6258113vnotesᵱ,1955[\,]^95[_ᐭaᓭᜧX/notesde_fSAXHandler.java

60importjava.io.*;importjava.util.Hashtable;importorg.xml.sax.*;publicclassSAXHandlerextendsHandlerBaseprivateHashtabletable=newHashtable();privateStringcurrentElement=null;privateStringcurrentValue=null;publicvoidsetTable(Hashtabletable)this.table=table;

61publicHashtablegetTable()returntable;publicvoidstartElement(Stringtag,AttributeListattrs)throwsSAXExceptioncurrentElement=tag;publicvoidcharacters(char[]ch,intstart,intlength)

62throwsSAXExceptioncurrentValue=newString(ch,start,length);)publicvoidendElement(Stringname)throwsSAXExceptionif(currentElement.equals(name))table.put(currentElement,currentValue);JSPᑁhijkṹ,SaxXml.jsp:

63<%@pageerrorPage="ErrPage.jsp"contentType="text/html;charset=GB2312n%><%@pageimport="java.io.*"%><%@pageimport=',java.utiLHashtablen%><%@pageimport=norg.w3c.dom.*n%><%@pageimport=Morg.xml.sax.*M%>

64<%@pageimport=njavax.xml.parsers.SAXParserFactoryn%><%@pageimport=Hjavax.xml.parsers.SAXParser"%><%@pageimport=HSAXHandler"%><%Filefile=newFile(,'c:\people.xmr,);FileReaderreader=newFileReader(file);Parserparser;SAXParserFactoryspf=SAXParserFactory.newInstance();SAXParsersp=spf.newSAXParser();SAXHandlerhandler=newSAXHandler();sp.parse(newInputSource(reader),handler);

65HashtablehashTable=handler.getTable();out.println(HᦟH⊤");out.println("vTR>op"+'"+(String)hashTable.get(newString(Hname"))+"H);out.println("vTD>X▾"+H"+(String)hashTable.get(newString(',college"))+,,H);out.println("vTRxTD>ᵯr"+,,n+(String)hashTable.get(newStringC^elephone"))+nn);out.println("vTR>vTD>ᜓt"+"M+(String)hashTable.get(newString("notes"))+n");out.println(uH);

66%>EJB)☢1ஹEJB2.0ᨵyzᑁh?ᑖ|ᵨᙠ}~ᔠEJB2.0EJB1.1Ḅ|?;ᑁhᒹBeanὅᵨQ!ὅEJBhᘤEJB!"ᐹEJBὅᳮᕒ஺☢EJBhᘤPEJBᡠ'Ḅ᪶஺EJBhᘤᳮḼEJBḄ¡¢£¤¥¦§¦ᦪ¨©Ḅª««¬⌕Ḅ᪶®஺JSP,Servlet,EJB,JNDI,JDBC,JMS..…2ஹEJBJAVABEANḄ|;:JavaBeanP&¯ᵨḄ°±JavaBean²³ᨵ´µḄᳮ¶·¸¹6º»Javaf0&'Pº»Bean஺¼½¾¿À>ᵫÂJavaBeanPÃhᘤᡠ¡¢Ä᝞Tomcat
Ḅᡠ'JavaBeanᐹᨵº»Å.Ḅ᪀⌼ᘤÈ᜜½¾JavaBean⌕ÊËSerializableÌᵨÂÊËBeanḄᢝÎឋ஺JavaBeanÊ▭·ÑÂÒCOMÓÔḄÕᙢQᑁCOM°×PØÃÙQÚ8Ḅ஺EnterpriseJavaBeanÑÂDCOM,ᓽᑖÜC°஺×PÝÂJavaḄÞQ)ß_ᵨÄRMDᢈáḄᡠ'EJB&'ÃÞQÚ8ÄÙQஹÙâãäå஺¼EJBæçÃÜèᙠé᝞Webspere^WebLogic᪵ḄhᘤEJBëᡝíØîÚ8ïðḄEJB°ñP½òᐸhᘤÚ8஺EJBhᘤPEJB°Ḅ?ᳮEJB°ᵫhᘤᡠ¡¢ᳮ஺ëᡝ½òhᘤᩭÚ8ïðḄEJB°஺3ஹEJBḄÝÕõ᪀

67;:º»EJBᒹö»÷ᑖ:RemoteInterfaceÌḄ?ṹpackageBeans;importjavax.ejb.EJBObject;importjava.rmi.RemoteException;publicinterfaceAddextendsEJBObject//somemethoddeclareHomeInterfaceÌḄ?ṹpackageBeans;

68importjava.rmi.RemoteException;importjaax.ejb.CreateException;importjavax.ejb.EJBHome;publicinterfaceAddHomeextendsEJBHome//somemethoddeclareEJBfḄ?ṹpackageBeans;importjava.rmi.RemoteException;importjavax.ejb.SessionBean;

69importjavx.ejb.SessionContext;publicclassAddBeanImplementsSessionBean//somemethoddeclare)J2EE,MVC)☢1ஹMVCḄᔜ»÷ᑖ0ᨵøzᢈáᩭÊË?᝞6ÊË?;:MVCPModel-View-ControllerḄùᑏ஺"Model"?⊤ḄPᵨḄûüýĽòJavaBean,EJB°ÊËå"View"PᵨḄ⊤j☢ÄᵫJSP⚓☢ÿ
"Controller"ᵨḄᜐᳮᑴServlet
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70:;ᜧ=⊡?@@3ஹJ2EEAB8C:Je22SunEFGḄHI(multi-diered),ᑖJK(distributed),LM$%(component-base)ḄNOPᵨ(enterprieseapplicationmodel).ᙠ᪵Ḅ•ᵨTUV*ᢥ᯿YZᑜᑖ\"#Ḅ$%)$%]*ᙠ"#^_?`aᜐMbḄIc(tier)V஺ᡠeIcᒹghᡝI(clietntier)$%,webI$%,BusinessI$%,NOklTU(EIS)I஺4ஹWEBSERVICEmnop஺JSWDLqrᒹḄst஺JAXPஹJAXMḄop஺SOAP,UDDI,WSDLop஺CuWebServicevwxyWSDLSOAPᓽ{ᓫ}~(SimpleObjectAccessProtocol),ᵨM.ᣚXMLṹklḄP஺UDDIḄḄ\ᵯᖪ3᪗UDDI-ᝅLMWebḄஹᑖJKḄஹ\WebServiceḄஹklVḄ&'᪗#ᒹ$NOZḄWebService+7ḄNOZr'ḄḄ&'᪗஺5ஹBS5CSḄὶT567஺:;ᜧ=⊡ᓃ@@

716ஹSTRUTSḄᵨ᝞STRUTS¤᪀
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72ᔠäë
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73else{document.form1,all(i).value=parseFloat(str);}CORBAÈ☢1ஹCORBAAB?ᵨ⌶AB8CuCORBA᪗Eᐳ}~±²öᳮ÷᪀(CommonObjectRequestBrokerArchitecture),ᵫ}~øᳮ$ù(ObjectManagementGroup,úᑏ\OMG)᪗ᓄ஺Ḅ$ᡂüýþÿ
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745LINUX67Ḅ89:;᪶=>?@#Ḅ"BCB"/DE0BF/6GCBF᪶=>?@#0H/IḄJᳮᙠ᪶᜜MᦪO$67஺GDI1PQᜓST1O஺JAVAU☢V⚪JAVA+☢1☢ᔣCYḄᱯ[ᨵ]^+☢2String9ᨬ:`Ḅᦪa1Eᔩ?3intIntegerᨵdefg4StringStringBufferḄfg5%&hijkBBlijᨵminij⊤p%&q$rst7Ḅuvjw᝱0%&hij⊤pyz{Ḅ|j$rs⍗ᑮḄij09j%&┯஺javaᘤ⌕+trs*Ḅu%&hij09⌕tᣓḄ%&hij஺

756tB^jᵨḄ10ᒹ,ST0ᔜ5F7tArrayList,Vector,LinkedListḄឋsᱯឋAn-ayListVector9ᵨᦪ+ᦪa0ᦪᐗ¢ᦪᜧ;6▭Ḅᦪa¥¦§¨©ᐭᐗ¢0«¬ᐕSᢥ¯°±ᐗ¢09©ᐭᐗ¢⌕²³ᦪᐗ¢´µ¶ᑁ0ᡠ¥°±ᦪa¹H©ᐭᦪa᠒0Vectorᵫ;ᵨ¼synchronized+½/¾ᐰÀ0|jឋsÁÂArrayListÃ0HLinkedListᵨÄᔣÅ⊤670ᢥ¯°±ᦪa◤⌕#&ÇᔣᡈÉᔣÊᔊ09©ᐭᦪahÌ◤⌕ÍÎ`⚗ḄÇÉ⚗ᓽr0ᡠ¥©ᐭÑÒ¹஺84F/0ᐸ$ÓF/ÔÕCj§¨1,Ö᜜ÓF/CjÔÕ×ØI஺ᑏt஺¥.ᵨᑁÙ167/0Cj§×Ḅh᎛Ûᨵὃ⇋Þß⚪஺publicclassThreadTestl{privateintj;publicstaticvoidmain(Stringargs[]){ThreadTest1tt=newThreadTestl();Incinc=tt.newInc();

76Decdec=tt.newDec();for(inti=0;i<2;i++){Threadt=newThread(inc);t.start();t=newThread(dec);t.start();privatesynchronizedvoidinc(){j++;System.out.println(Thread.cun-entThread().getName()+,,-inc:u+j);

77privatesynchronizedvoiddec(){System.out.println(Thread.currentThread().getName()4-u-dec:n+j);classIncimplementsRunnable{publicvoidrun(){for(inti=0;i<100;i++){inc();)

78classDecimplementsRunnable)publicvoidrun(){for(inti=0;i<100;i++){dec();)9.JSPḄᑁàCY³+஺

79requestrequest⊤pHttpServletRequestCY஺«ᒹá¼ᨵᐵãäᘤḄåæ0çèé¼êFᵨ;ëcookie,header,sessionᦪaḄᨵᵨḄ+஺responseresponse⊤pHttpServletResponseCY0èé¼ìFᵨ;à〈îãäᘤḄïḄ+(᝞cookies,ᜮåæ¶)outoutCY9javax.jsp.JspWriterḄBF6ó0èé¼êF+ôsᵨ;ᔣãäᘤî〈õtö÷஺pageContextpageContext⊤p——Fjavax.servlet.jsp.PageContextCY஺«9ᵨ;+¦ëᔜúḄûüýஹservletþᐵḄCYḄAPI,çᒹÿ
ᵨḄservletᐵḄ஺sessionsession⊤Ḅjavax.servlel.hllp.HttpSession஺SessionᵨᡝḄ᝱applicationapplicaton⊤•javax.servle.ServletContext஺ᨵ!"#ᨵᐵservlet$%&servlet'᛻Ḅconfigconfig⊤javax.servlet.ServletConhg஺)ᵨ!*servlet+,Ḅ-.ᓄ0ᦪ஺pagepage⊤2)⚓☢56Ḅservlet+,10.ᵨsocket
7ᑏ9:ᡝ;&<=ᘤ;Ḅ
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7,M஺11N9ServletḄ6OᕜQ,SN9Servlet&CGIḄTU஺ServletV<=ᘤ+,ᓄD?WᘤXYᐸinit?ᑮ\]XYᐸservice?service^_`⍧XY0bḄdoXXX(doGet,doPost)d?e<=ᘤfgh+,├jḄ]᎛lᵨᐸdestroy஺

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107JavaAdvancedImagingAPIᒹEᙠJavaMediaAPI:FᐕHᙠJava8ᵨ:᡻5JᩖḄLឋ2Ḅ<=ᜐᳮ.JAIAPIPQ,>?<=Ḅ2R.JAIAPIᢝ-S.<=ᦻBTU:BMP,JEPGPNGPNM,TIFF.V☢XY,;<=>?ᑮBMPᦻBḄ•[\ṹOutputStreamos=newFileOutputStream(fileToWriteTo);BMPEncodeParamparam=newBMPEncodeParam();ImageEncoderenc=ImageCodec.createImageEncoder("BMP",os,param);enc.encode(img);os.close();ᨵᐵ>?<=ᦻBḄ_`ᢣᓭcdὃ-Vf⚓http://java.sun.com/products/java-media/jai/forDevelopers/jai-guide/25ஹ:᝞ᵨJavahiᔣklmᑏᦪpCfont>SunḄJavaCommunicationAPI2.0qᵨrmᑏkl/ᢝRS232klIEEE1284slPQ,"tuvwᐵḄk/slyz{ᑴ.postedon2006-07-1810:32}~▅m(1626)(2)_ᦈᡠᑖFeedBack:#re:ᦈḄJAVA☢⚪ᜧᐰ2006-07-1810:331}http://community.csdn.net/Expert/topic/4295/4295702.xml?temp=.5789759ᜧ#⚪)H-☢ᨵ1.☢ᔣḄᱯᨵ#&☢C¡¢ឋ£᝱ឋ¥¦ឋ

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1097.Þáint±Ḅ᦮ᦪâãä$3&åæÌ5çᣚC᝞a=10b=5èᣚa=5b=10&é"ஹa=a+b;b=a-b;a=a-b;&éêஹa=a+b«16;//bëᑮ,aḄL16ìb=(a&0XFFFF0000)»16஻Öaëᑮ,aḄL16ìa=a&OxOOOOffff;&é%ஹaA=b;bA=a;aA=b;8.᣸┯⚪1.publicBaseVOgetAll(Stringid)ᵫrowsSQLException{PreparedStatementps=null;BaseVbvo=null;ResultSetrs=null;Listlist=null;Stringsql="select*frombase_infowhereid="+id1';ps=dbConnection.prepareStatement(sql);try(rs=ps.executeQuery();if(rs.next()){vo=fillVO(rs);))catch(SQLExceptione){throwe;)finally{closeDBObject(ps,rs);returnvo;))2.publicbooleancompare(Stringstr,Listlist){

110list=newArrayList();intlen=list.size();booleanb=false;fbr(inti=0;iendtrueyyyy-mm-ddhh:ss
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111Stringstr="ᡃJAVA:)”for(inti=O;iv=str.length();i++){஻ᡭᓺSystem.out.println(cutString(str,i))))publicstaticStringcutString(Strings,intlen){byte[]sb=s.getBytes();booleanb=true;for(inti=0;i127)n-)returnstr.substring(O,n);vz{,᝞abcdd,ᡠᨵḄzᔠ(᝞abacadddd.......)!publicclassGenCombination(charnumfl;publicGenCombination(inti,char[]ia){num=newchar[i];for(intj=O;j

112publicintgetCombination(intn,intm){if(n=SecondParam");return0;)System.out.println("get"+m+ucharfrom"+n+"char:u);intnumOfResult=0;charresult[][]=newcharf100][];inta;a=newint[m+l];intij;for(i=l;i<=m;i++)a[i]=i;for(;;)(result[numOfResult]=newchar[m];inth=0;for(i=li<=m;i++){result[numOfResult][h]=num[a[i]-l];h++;)for(intp=0;p=l;j-)if(a[j]

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116returnnumOfResult;)publicstaticvoidmain(Stringargs[])(Strings="abcddn;charca[]=s.toCharArray();GenCombinationgc=newGenCombination(s.length(),ca);for(inti=l;i<=s.length();i++)gc.getCombination(s.length(),i);1HashMapHashTableᨵ¡¢2ᦪ%&Zᨵ4ᦪ%ID(pri)(Auto)namepass1aaa1112bbb2223ccc333ᵨvᩩSQL£¤UᨵḄ¥ᩩ¦§¨ᑴv,ªᑮ4Ḅᦔ
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117namevarcharbirthDayDateᵨjavaᑏvw|ᦪ,ᡠᨵ{ᔠᩩno=inta&name=str$birthdavy=dateḄÀ
Âᔠ5jspServletḄ¡¢ὶÄ6ÅÆvwᩗ▲ÉᳮÊË,ᑖa&bÌaḄvÍᵨᡝLryaḄtable,aZḄÉᳮᕒ4ÏaḄtableÐÑCRUDÒ᪵,bḄvÍᵨᡝLrybḄtable,bZḄÉᳮᕒ4ÏbḄtableÐÑCRUDÓÔÉᳮᕒ4Ïa&bḄlableÐÑCRUDᑏÕᑖÖṹ¨×ØÙ=#re:ᦈÛḄJAVA☢Ü⚪ᜧᐰ2006-07-3113:391àáâãäåhttp://www.blogjava.net/axyh/archive/2006/07/31/60946.html1.WhydoyoupreferJava?Answer:writeonce,runanywhere.2.Namesomeoftheclasseswhichprovidethefunctionalityofcollation?Answer:collator,rulebasedcollator,collationkey,collationelementiterator.3.Awtstandsfor?andwhatisit?Answer:AWTstandsforAbstractwindowtoolkit.Itisaisapackagethatprovidesanintegratedsetofclassestomanageuserinterfacecomponents.4.whyajavaprogramcannotdirectlycommunicatewithanODBCdriver?Answer:SinceODBCAPIiswritteninClanguageandmakesuseofpointerswhichJavacannotsupport.5.Areservletsplatformindependent?IfsoWhy?Alsowhatisthemostcommonapplicationofservlets?AnsweæYes,BecausetheyarewritteninJava.ThemostcommonapplicationofservletistoaccessdatabaseanddynamicallyconstructHTTPresponse6.WhatisaServlet?Answer:ServletsaremodulesofJavacodethatruninaserverapplication(hencethename"Servlets",similarto"Applets"ontheclientside)toanswerclientrequests.7.WhatadvantagesdoesCMOShaveoverTTL(transitortransitorlogic)?(ALCATEL)Answer:lowpowerdissipationpullsuptoraileasytointerface8.HowisJavaunlikeC++?(AskedbySun)SomelanguagefeaturesofC++havebeenremoved.StringmanipulationsinJavadonotallowforbufferoverflowsandothertypicalattacks.OS-specificcallsarenotadvised,butyoucanstillcallnativemethods.EverythingisaclassinJava.EverythingiscompiledtoJavabytecode,not

118executable(althoughthatispossiblewithcompilertools).9.WhatisHTML(HypertextMarkupLanguage)?HTML(HyperTextMarkupLanguage)isthesetof"markup"symbolsortagsinsertedinafileintendedfordisplayonaWorldWideWebbrowser.ThemarkuptellstheWebbrowserhowtodisplayaWebpage'swordsandimagesfortheuser.lO.Defineclass.Answer:Aclassdescribesasetofproperties(primitivesandobjects)andbehaviors(methods).1l.InJava,whatisthedifferencebetweenanInterfaceandanAbstractclass?A:AnAbstractclassdeclareshaveatleastoneinstancemethodthatisdeclaredabstractwhichwillbeimplementedbythesubclasses.Anabstractclasscanhaveinstancemethodsthatimplementadefaultbehavior.AnInterfacecanonlydeclareconstantsandinstancemethods,butcannotimplementdefaultbehavior.12.CanyouhavevirtualfunctionsinJava?YesorNo.Ifyes,thenwhatarevirtualfunctions?A:Yes,Javaclassfunctionsarevirtualbydefault.Virtualfunctionsarefunctionsofsubclassesthatcanbeinvokedfromareferencetotheirsuperclass.Inotherwords,thefunctionsoftheactualobjectarecalledwhenafunctionisinvokedonthereferencetothatobject.13.WriteafunctiontoreversealinkedlistpinC++?A:Link*reverse_list(Link*p)(if(p==NULL)returnNULL;Link*h=p;p=p->next;h->next=NULL;while(p!=null)(Link*t=p->next;p->next=h;h=p;p=t;)returnh;)14.1nC++,whatistheusefulnessofVirtualdestructors?A:Virtualdestructorsareneccessarytoreclaimmemorythatwereallocatedforobjectsintheclasshierarchy.Ifapointertoabaseclassobjectisdeleted,thenthecompilerguaranteesthevarioussubclassdestructorsarecalledinreverseorderoftheobjectconstructionchain.15.Whataremutexandsemaphore?Whatisthedifferencebetweenthem?A:Amutexisasynchronizationobjectthatallowsonlyoneprocessorthreadtoaccessacriticalcodeblock.Asemaphoreontheotherhandallowsoneormoreprocessesorthreadstoaccessacritialcodeblock.Asemaphoreisamultiplemutex.