Week five study record

Job 1: Displays all files under the specified directory in the list box (JList) component.
The code is as follows:
Import java.awt. ;
Import java.awt.event.;
Import javax.swing. ;
Import javax.swing.event.;
Import javax.swing.border.*;

Import java.util.List;
Import java.util.ArrayList;

Import java.io.*;

 Public classWjextendsJFrameImplementsChangeListener, actionlistener{Private Static FinalString Version = "Version 1.0";Private Static FinalString wenj_dir = "File";PrivateJList fileList;PrivateSoundengine player; Public Static voidMain (string[] args) {WJ GUI=NewWJ ();} PublicWJ () {Super("File"); Player=NewSoundengine (); String[] FileNames= FindFiles (Wenj_dir,NULL); Makeframe (FileNames);}Private voidquit () {System.exit (0);}Private voidshowabout () {Joptionpane.showmessagedialog ( This,                 "File \ n" +VERSION,"About File", joptionpane.information_message);}Privatestring[] FindFiles (string dirName, string suffix) {File dir=NewFile (dirName); if(Dir.isdirectory ()) {string[] allfiles=dir.list (); if(Suffix = =NULL) {            returnAllfiles; }        Else{List<String> selected =NewArraylist<string>();  for(String filename:allfiles) {if(filename.endswith (suffix)) {selected.add (filename); }            }            returnSelected.toarray (Newstring[selected.size ()]); }    }    Else{System.out.println ("Error:" + dirName + "must be a directory"); return NULL; }} Public voidstatechanged (ChangeEvent evt) {}//Add Listener Public voidactionperformed (ActionEvent evt) {JComboBox CB=(JComboBox) Evt.getsource (); String format=(String) Cb.getselecteditem (); if(Format.equals ("All") ) {format=NULL; } filelist.setlistdata (FindFiles (wenj_dir, format));}Private voidmakeframe (string[] Files) {setdefaultcloseoperation (exit_on_close); JPanel ContentPane=(JPanel) Getcontentpane (); Contentpane.setborder (NewEmptyborder (6, 10, 10, 10));        Makemenubar (); Contentpane.setlayout (NewBorderLayout (8, 8)); JPanel Leftpane=NewJPanel (); {Leftpane.setlayout (NewBorderLayout (8, 8)); string[] Formats= {"All", ". Doc", ". png", ". mp3" }; JComboBox formatlist=NewJComboBox (formats); Formatlist.addactionlistener ( This);           Leftpane.add (Formatlist, Borderlayout.north); FileList=NewJList (Files); Filelist.setforeground (NewColor (140,171,226)); Filelist.setbackground (NewColor (0,0,0)); Filelist.setselectionbackground (NewColor (87,49,134)); Filelist.setselectionforeground (NewColor (140,171,226)); JScrollPane ScrollPane=NewJScrollPane (fileList); Scrollpane.setcolumnheaderview (NewJLabel ("Wenj Files"));    Leftpane.add (ScrollPane, Borderlayout.center);     } contentpane.add (Leftpane, Borderlayout.center);       Pack (); Dimension D=Toolkit.getdefaulttoolkit (). Getscreensize (); setlocation (D.width/2-getwidth ()/2, D.HEIGHT/2-getheight ()/2); SetVisible (true);}//setting Menu ItemsPrivate voidMakemenubar () {Final intShortcut_mask =Toolkit.getdefaulttoolkit (). Getmenushortcutkeymask (); JMenuBar MenuBar=NewJMenuBar ();        Setjmenubar (menubar);    JMenu menu;           JMenuItem item; Menu=NewJMenu ("File");        Menubar.add (menu); Item=NewJMenuItem ("Quit");        Item.setaccelerator (Keystroke.getkeystroke (Keyevent.vk_q, shortcut_mask)); Item.addactionlistener (NewActionListener () { Public voidactionperformed (ActionEvent e) {quit ();}    });    Menu.add (item); Menu=NewJMenu ("Help");        Menubar.add (menu); Item=NewJMenuItem ("About ..."); Item.addactionlistener (NewActionListener () { Public voidactionperformed (ActionEvent e) {showabout ();}    }); Menu.add (item);}}

Interface diagram:

Job 2: Output the highest recorded player information in the game.
Method: This can use the Seek () method to jump the pointer and the Getfilepointer () method to get the current pointer position implementation.
The code is as follows:
Import Java.io.File;
Import java.io.IOException;
Import Java.io.RandomAccessFile;

 Public classtestrandomaccessfile{Privatefile file; Public Static voidMain (string[] args) {testrandomaccessfile Traf=Newtestrandomaccessfile (); Traf.init (); Traf.record ("Adom", 80); Traf.listallrecords ();} Public voidRecord (String Record_breaker,intTimes ) {    Try{Randomaccessfile RAF=NewRandomaccessfile (file, "RW"); BooleanFlag =false;  while(Raf.getfilepointer () <raf.length ()) {String name=Raf.readutf (); LongPrior =Raf.getfilepointer (); if(record_breaker.equalsignorecase (name)) {flag=true; //Compare the number of passes in and the size of the previous number                                 if(Raf.readint () <Times ) {                                    //use the Seek () method to jump to the location of the priorRaf.seek (Prior);                                     Raf.writeint (times);  Break; }                             } Else{raf.skipbytes (4); }                             }        if(!flag)            {Raf.writeutf (Record_breaker);            Raf.writeint (times);                    } raf.close (); }Catch(Exception e) {e.printstacktrace (); }} Public voidinit () {if(File = =NULL) {file=NewFile ("Record.txt"); Try{file.createnewfile (); }Catch(IOException e) {e.printstacktrace (); }       }   } Public voidlistallrecords () {Try{Randomaccessfile RAF=NewRandomaccessfile (file, "R");  while(Raf.getfilepointer () <raf.length ()) {String name=Raf.readutf (); intTimes =Raf.readint (); System.out.println ("Name:" + name + "\trecord:" +Times );                    } raf.close (); }Catch(Exception e) {e.printstacktrace (); }       }}

Interface diagram:

Week five study record