Java做的一个小程序,随机点名器

Java做的一个小程序，随机点名器1.importjava.io.*;2.importjava.awt.*;3.importjava.awt.event.*;4.importjava.util.List;5.importjava.util.ArrayList;6.7.publicclassDianNameextendsFrame{8.9.privateStringfileName=a.txt;10.privateFilef;11.privateFileReaderfr;12.privateBufferedReaderbr;13.privateListStringnames=newArrayListString();14.privateStringstrName;15.16.privateLabellabelName;17.privateButtonbtOK;18.19.publicstaticvoidmain(String[]args){20.DianNamedn=newDianName();21.dn.newFrame();22.dn.read();23.}24.25.publicvoidnewFrame(){26.labelName=newLabel(显示姓名);27.btOK=newButton(开始);28.29.this.setLocation(300,300);30.this.setResizable(false);31.this.setSize(500,400);32.this.add(labelName,BorderLayout.NORTH);33.this.add(btOK,BorderLayout.SOUTH);34.this.pack();35.this.setVisible(true);36.this.addWindowListener(newWindowAdapter(){37.publicvoidwindowClosing(WindowEvente){38.System.exit(0);39.}40.});41.btOK.addActionListener(newButtonAction());42.}43.44.publicvoidread(){45.try{46.f=newFile(fileName);47.if(!f.exists()){48.f.createNewFile();49.}50.fr=newFileReader(f);51.br=newBufferedReader(fr);52.Stringstr=br.readLine();53.while(str!=null){54.names.add(str);55.str=br.readLine();56.}57.}catch(Exceptione){58.e.printStackTrace();59.}60.61.}62.63.publicvoidwrite(){64.try{65.intindex=(int)(Math.random()*names.size());66.strName=names.get(index);67.}catch(Exceptione){68.e.printStackTrace();69.}70.71.}72.73.privateclassButtonActionimplementsActionListener{74.publicvoidactionPerformed(ActionEvente){75.write();76.labelName.setText(strName);77.}78.}79.}