java经典代码(最全面).doc

Java实现ftp功能.ftp.*; .*; importjava.awt.*; importjava.awt.event.*; importjava.applet.*; importjava.io.*; publicclassFtpAppletextendsApplet FtpClientaftp; DataOutputStreamoutputs; TelnetInputStreamins; TelnetOutputStreamouts; TextArealsArea; LabelLblPrompt; ButtonBtnConn; ButtonBtnClose; TextFieldTxtUID; TextFieldTxtPWD; TextFieldTxtHost; intch; publicStringa=没有连接主机; Stringhostname=; publicvoidinit() setBackground(Color.white); setLayout(newGridBagLayout(); GridBagConstraintsGBC=newGridBagConstraints(); LblPrompt=newLabel(没有连接主机); LblPrompt.setAlignment(Label.LEFT); BtnConn=newButton(连接); BtnClose=newButton(断开); BtnClose.enable(false); TxtUID=newTextField(,15); TxtPWD=newTextField(,15); TxtPWD.setEchoCharacter(*); TxtHost=newTextField(,20); LabelLblUID=newLabel(UserID:); LabelLblPWD=newLabel(PWD:); LabelLblHost=newLabel(Host:); lsArea=newTextArea(30,80); lsArea.setEditable(false); GBC.gridwidth=GridBagConstraints.REMAINDER; GBC.fill=GridBagConstraints.HORIZONTAL; (GridBagLayout)getLayout().setConstraints(LblPrompt,GBC); add(LblPrompt); GBC.gridwidth=1; (GridBagLayout)getLayout().setConstraints(LblHost,GBC); add(LblHost); GBC.gridwidth=GridBagConstraints.REMAINDER; (GridBagLayout)getLayout().setConstraints(TxtHost,GBC); add(TxtHost); GBC.gridwidth=1; (GridBagLayout)getLayout().setConstraints(LblUID,GBC); add(LblUID); GBC.gridwidth=1; (GridBagLayout)getLayout().setConstraints(TxtUID,GBC); add(TxtUID); GBC.gridwidth=1; (GridBagLayout)getLayout().setConstraints(LblPWD,GBC); add(LblPWD); GBC.gridwidth=1; (GridBagLayout)getLayout().setConstraints(TxtPWD,GBC); add(TxtPWD); GBC.gridwidth=1; GBC.weightx=2; (GridBagLayout)getLayout().setConstraints(BtnConn,GBC); add(BtnConn); GBC.gridwidth=GridBagConstraints.REMAINDER; (GridBagLayout)getLayout().setConstraints(BtnClose,GBC); add(BtnClose); GBC.gridwidth=GridBagConstraints.REMAINDER; GBC.fill=GridBagConstraints.HORIZONTAL; (GridBagLayout)getLayout().setConstraints(lsArea,GBC); add(lsArea); publicbooleanconnect(Stringhostname,Stringuid,Stringpwd) this.hostname=hostname; LblPrompt.setText(正在连接，请等待.); try aftp=newFtpClient(hostname); aftp.login(uid,pwd); aftp.binary(); showFileContents(); catch(FtpLoginExceptione) a=无权限与主机:+hostname+连接!; LblPrompt.setText(a); returnfalse; catch(IOExceptione) a=连接主机:+hostname+失败!; LblPrompt.setText(a); returnfalse; catch(SecurityExceptione) a=无权限与主机:+hostname+连接!; LblPrompt.setText(a); returnfalse; LblPrompt.setText(连接主机:+hostname+成功!); returntrue; publicvoidstop() try aftp.closeServer(); catch(IOExceptione) publicvoidpaint(Graphicsg) publicbooleanaction(Eventevt,Objectobj) if(evt.target=BtnConn) LblPrompt.setText(正在连接，请等待.); if(connect(TxtHost.getText(),TxtUID.getText(),TxtPWD.getText() BtnConn.setEnabled(false); BtnClose.setEnabled(true); returntrue; if(evt.target=BtnClose) stop(); BtnConn.enable(true); BtnClose.enable(false); LblPrompt.setText(与主机+hostname+连接已断开!); returntrue; returnsuper.action(evt,obj); publicbooleansendFile(Stringfilepathname) booleanresult=true; if(aftp!=null) LblPrompt.setText(正在粘贴文件,请耐心等待.); Stringcontentperline; try a=粘贴成功!; Stringfg=newString(); intindex=filepathname.lastIndexOf(fg); Stringfilename=filepathname.substring(index+1); FilelocalFile; localFile=newFile(filepathname); RandomAccessFilesendFile=newRandomAccessFile(filepathname,r); / sendFile.seek(0); outs=aftp.put(filename); outputs=newDataOutputStream(outs); while(sendFile.getFilePointer()=0) buf.append(char)ch); lsArea.appendText(buf.toString(); ins.close(); catch(IOExceptione) publicstaticvoidmain(Stringargs) Framef=newFrame(FTPClient); f.addWindowListener(newWindowAdapter() publicvoidwindowClosing(WindowEvente) System.exit(0); ); FtpAppletftp=newFtpApplet(); ftp.init(); ftp.start(); f.add(ftp); f.pack(); f.setVisible(true); Java URL编程importjava.io.*; .*; / / /GetHost.java / / publicclassGetHost publicstaticvoidmain(Stringarg) if(arg.length=1) InetAddressInet; inti=1; try for(i=1;i=arg.length;i+) Inet=InetAddress.getAllByName(argi-1); for(intj=1;j=Inet.length;j+) System.out.print(Inetj-1.toString(); System.out.print(n); catch(UnknownHostExceptione) System.out.print(UnknownHostName!+argi-1); else System.out.print(Usagejava/jviewGetIp); Example2 downloadnow /GetHTML.java /* *Thisisaprogramwhichcanreadinformationfromawebserver. *version1.02000/01/01 *authorjdeveloper */ .*; importjava.io.*; publicclassGetHTML publicstaticvoidmain(Stringargs) if(args.length1) System.out.println(USAGE:javaGetHTMLhttpaddress); System.exit(1); StringsURLAddress=newString(args0); URLurl=null; try url=newURL(sURLAddress); catch(MalformedURLExceptione) System.err.println(e.toString(); System.exit(1); try InputStreamins=url.openStream(); BufferedReaderbreader=newBufferedReader(newInputStreamReader(ins); Stringinfo=breader.readLine(); while(info!=null) System.out.println(info); info=breader.readLine(); catch(IOExceptione) System.err.println(e.toString(); System.exit(1); Java RMI编程Step1:ImplementstheinterfaceofRemoteServerasSimpleCounterServer.java publicinterfaceSimpleCounterServerextendsjava.rmi.Remote publicintgetCount()throwsjava.rmi.RemoteException; CompileitwithjavacSimpleCounterServer.java Step2:ProducetheimplementfileSimpleCounterServerImpl.javaas importjava.rmi.*; importjava.rmi.server.UnicastRemoteObject; / / /SimpleCounterServerImpl / / publicclassSimpleCounterServerImpl extendsUnicastRemoteObject implementsSimpleCounterServer privateintiCount; publicSimpleCounterServerImpl()throwsjava.rmi.RemoteException iCount=0; publicintgetCount()throwsRemoteException return+iCount; publicstaticvoidmain(Stringargs) System.setSecurityManager(newRMISecurityManager(); try SimpleCounterServerImplserver=newSimpleCounterServerImpl(); System.out.println(SimpleCounterServercreated); Naming.rebind(SimpleCounterServer,server); System.out.println(SimpleCounterServerregistered); catch(RemoteExceptionx) x.printStackTrace(); catch(Exceptionx) x.printStackTrace(); ComplileitwithjavacSimpleCounterServerImpl.java Step3:ProduceskeletonandstubfilewithrmicSimpleCounterServerImpl Youwillgettwoclassfiles: 1.SimpleCounterServerImpl_Stub.class 2.SimpleCounterServerImpl_Skel.class Step4:startrmiregistry Step5:javaSimpleCounterServerImpl Step6:ImplementstheClientApplettoinvoketheRemotemethod File:SimpleCounterApplet.javaas importjava.applet.Applet; importjava.rmi.*; importjava.awt.*; / / /SimpleCounterApplet / / publicclassSimpleCounterAppletextendsApplet Stringmessage=; Stringmessage1=; publicvoidinit() setBackground(Color.white); try SimpleCounterServersever=(SimpleCounterServer) Naming.lookup(/+getCodeBase().getHost()+/SimpleCounterServer); message1=/+getCodeBase().getHost()+/SimpleCounterServer; message=String.valueOf(sever.getCount(); catch(Exceptionx) x.printStackTrace(); message=x.toString(); publicvoidpaint(Graphicsg) g.drawString(Numberis+message,10,10); g.drawString(Numberis+message1,10,30); step7createanHtmlFilermi.htm: Java CORBA入门BelowisasimpleexampleofaCORBAprogram downloadthesourcefile 1.produceaidlfilelikethis hello.idl moduleHelloApp interfaceHello stringsayHello(); ; ; 2.producestubandskeletonfilesthroughidltojava.exe idltojavahello.idl idltojavaisnownamedasidlj.exeandisincludedintheJDK. 3.writeaserverprogramlikethis /HelloServer.java importHelloApp.*; importorg.omg.CosNaming.*; importorg.omg.CosNaming.NamingContextPackage.*; importorg.omg.CORBA.*; importjava.io.*; classHelloServantextends_HelloImplBase publicStringsayHello() returnnHelloworld!n; publicclassHelloServer publicstaticvoidmain(Stringargs) try /createandinitializetheORB ORBorb=ORB.init(args,null); /createservantandregisteritwiththeORB HelloServanthelloRef=newHelloServant(); orb.connect(helloRef); /gettherootnamingcontext org.omg.CORBA.ObjectobjRef= orb.resolve_initial_references(NameService); NamingContextncRef=NamingContextHelper.narrow(objRef); /bindtheObjectReferenceinNaming NameComponentnc=newNameComponent(Hello,); NameComponentpath=nc; ncRef.rebind(path,helloRef); /waitforinvocationsfromclients java.lang.Objectsync=newjava.lang.Object(); synchronized(sync) sync.wait(); catch(Exceptione) System.err.println(ERROR:+e); e.printStackTrace(System.out); 4.writeaclientprogramlikethis /HelloClient.java importHelloApp.*; importorg.omg.CosNaming.*; importorg.omg.CORBA.*; publicclassHelloClient publicstaticvoidmain(Stringargs) try /createandinitializetheORB ORBorb=ORB.init(args,null); /gettherootnamingcontext org.omg.CORBA.ObjectobjRef= orb.resolve_initial_references(NameService); NamingContextncRef=NamingContextHelper.narrow(objRef); /test System.out.println(OK.); /resolvetheObjectReferenceinNaming NameComponentnc=newNameComponent(Hello,); NameComponentpath=nc; HellohelloRef=HelloHelper.narrow(ncRef.resolve(path); /calltheHelloserverobjectandprintresults /Stringoldhello=helloRef.lastMessage(); /System.out.println(oldhello); StringHello=helloRef.sayHello(); System.out.println(Hello); catch(Exceptione) System.out.println(ERROR:+e); e.printStackTrace(System.out); 5.compliethesefiles javac*.javaHelloApp/*.java 6.runtheapplication a.firstyouvetoruntheNameServicepriortotheotherslikethis c:tnameserv b.runserver c:javaHelloServer c.runclient c:javaHelloClient利用RamdonAccessFile来实现文件的追加RamdonAccessFile是个很好用的类，功能十分强大，可以利用它的 length()和seek()方法来轻松实现文件的追加，相信我下面这个例子是 很容易看懂的，先写入十行，用length()读出长度（以byte为单位）， 在用seek()移动到文件末尾，继续添加，最后显示记录。 importjava.io.*; publicclassIOStreamDemo publicstaticvoidmain(Stringargs) try RandomAccessFilerf1=newRandomAccessFile(d:jeru.txt,rw); for(inti=0;i<10;i+) rf1.writeBytes(xixi,thisisline+i+n); rf1.close(); inti=0; Stringrecord=newString(); RandomAccessFilerf2=newRandomAccessFile(d:jeru.txt,rw); rf2.seek(rf2.length(); rf2.writeBytes(lala,appendline+n); rf2.close(); RandomAccessFilerf3=newRandomAccessFile(d:jeru.txt,r); while(record=rf3.readLine()!=null) i+; System.out.println(Value+i+:+record); rf3.close(); catch(Exceptione) 把JavaMail包装成简单的Sendmailpackagesteeven; /* Calss:Sendmail Author: QQ:7461522 Date:11/13/2001 Notes: Findsamplesinmain(); Ifyousendmailonlyfrom/tointranet,changedomainasuneed. Setup: 1.changehost,mailFooter */ importjava.util.*; importjava.sql.*; importjavax.mail.*; ernet.*; importjavax.activation.*; publicclassSendmailextendsCommon publicStringhost=smtpServer;/smtpserver staticStringmailFooter=nnn此邮件由WebMail发送http:/www/mail.jspnn; Stringdomain=company; booleansessionDebug; Messagemsg; Multipartmultipart; publicSendmail()throwsException Propertiesprops=System.getProperties(); props.put(mail.host,host); props.put(tocol,smtp); Sessionsession=Session.getDefaultInstance(props,null); /SetdebugontheSessionsowecanseewhatisgoingon /Passingfalsewillnotechodebuginfo,andpassingtrue /will. session.setDebug(sessionDebug); /InstantiateanewMimeMessageandfillitwiththe /requiredinformation. msg=newMimeMessage(session); msg.setSentDate(newjava.util.Date(); multipart=newMimeMultipart(); msg.setContent(multipart); publicSendmail(Stringto,Stringfrom,Stringsubject,Stringbody)throwsException this(); this.setSendTo(to); this.setFrom(from); this.setSubject(subject); this.setBody(body); publicSendmail(Stringto,Stringfrom,Stringsubject,Stringbody)throwsException this(); this.setSendTo(to); this.setFrom(from); this.setSubject(subject); this.setBody(body); publicvoidsetHost(Stringhost)throwsException this.host=host; voidsetFrom(Stringfrom)throwsException msg.setFrom(newInternetAddress(from+domain); voidsetSendTo(Stringto)throwsException for(inti=0;i<to.length;i+) setSendTo(toi); voidsetSendTo(Stringto)throwsException /System.out.println(sendingmailto:+toi); InternetAddressaddress=newInternetAddress(to+domain); msg.setRecipients(Message.RecipientType.TO,address); voidsetCopyTo(Stringto)throwsException for(inti=0;to!=null&i<to.length;i+) setCopyTo(toi); voidsetCopyTo(Stringto)throwsException /System.out.println(Copyingmailto:+toi); InternetAddressaddress=newInternetAddress(to+domain); msg.setRecipients(Message.RecipientType.CC,address); voidsetSubject(Stringsubject)throwsException sun.misc.BASE64Encoderenc=newsun.misc.BASE64Encoder(); msg.setSubject(=?GB2312?B?+enc.encode(subject.getBytes()+?=); voidsetBody(Stringbody)throwsException MimeBodyPartmessageBodyPart=newMimeBodyPart(); messageBodyPart.setText(body+mailFooter); multipart.addBodyPart(messageBodyPart); voidsetAttachFile(StringfileName)throwsException setAttachFile(fileName,fileName); voidsetAttachFile(StringfileName,Stringname)throwsException MimeBodyPartmessageBodyPart=newMimeBodyPart(); DataSourcesource=newFileDataSource(fileName); messageBodyPart.setDataHandler(newDataHandler(source); messageBodyPart.setFileName(name); multipart.addBodyPart(messageBodyPart); voidsetAttachFile(StringfileName)throwsException for(inti=0;i<fileName.length;i+) setAttachFile(fileNamei0,fileNamei1); publicvoidsend()throwsException Transport.send(msg); publicstaticvoidmain(Stringargs)throwsExcept