Java Implementation simple Calculator function

Children's shoes, is not the use of calculators, but also to enter the run, Input calc, too troublesome, and sometimes even forget how to spell the word, hehe
programmers write their own code implementation, and simple, and convenient AH

The following is the code (you might want to build an executable tool for reference:http://www.cnblogs.com/holdon521/p/4483966.html)

 Packagecom;Importjava.awt.BorderLayout;ImportJava.awt.EventQueue;ImportJava.awt.Font;Importjava.awt.GridLayout;Importjava.awt.event.ActionEvent;ImportJava.awt.event.ActionListener;ImportJavax.swing.JButton;ImportJavax.swing.JFrame;ImportJavax.swing.JPanel;ImportJavax.swing.JTextField;Importjavax.swing.SwingConstants;ImportJavax.swing.UIManager;ImportJavax.swing.border.EmptyBorder; Public classTestextendsjframe{/*** Humphrey*/  Private Static Final LongSerialversionuid = -9075562467166618473l; PrivateJPanel ContentPane; PrivateJTextField display; PrivateActionListener Insert =Newinsertaction (); PrivateActionListener Command =Newcommandaction (); Private Doubleresult = 0; PrivateString Lastcommand = "="; Private BooleanStart =true; /*** Launch the application. */   Public Static voidMain (string[] args) {Try{Uimanager.setlookandfeel ("Com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel"); } Catch(Throwable e) {e.printstacktrace (); } eventqueue.invokelater (NewRunnable () { Public voidrun () {Try{Test frame=NewTest (); Frame.setvisible (true); } Catch(Exception e) {e.printstacktrace ();  }          }      }); }    /*** Create the frame. */   PublicTest () {Settitle ("\u8ba1\u7b97\u5668");      Setdefaultcloseoperation (Jframe.exit_on_close); Setlocationbyplatform (true); ContentPane=NewJPanel (); Contentpane.setborder (NewEmptyborder (5, 5, 5, 5)); Contentpane.setlayout (NewBorderLayout (0, 0));            Setcontentpane (ContentPane); JPanel DisplayPanel=NewJPanel ();            Contentpane.add (DisplayPanel, Borderlayout.north); Display=NewJTextField (); Display.settext ("0");      Display.sethorizontalalignment (Swingconstants.right); Display.seteditable (false); Display.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));      Displaypanel.add (display); Display.setcolumns (13); JPanel Buttonpanel=NewJPanel ();      Contentpane.add (Buttonpanel, Borderlayout.center); Buttonpanel.setlayout (NewGridLayout (4, 4, 5, 5)); JButton Number7button=NewJButton ("7");      Number7button.addactionlistener (insert); Number7button.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Number7button); JButton Number8button=NewJButton ("8");      Number8button.addactionlistener (insert); Number8button.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Number8button); JButton Number9button=NewJButton ("9");      Number9button.addactionlistener (insert); Number9button.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Number9button); JButton Dividebutton=NewJButton ("/");      Dividebutton.addactionlistener (command); Dividebutton.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Dividebutton); JButton Number4button=NewJButton ("4");      Number4button.addactionlistener (insert); Number4button.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Number4button); JButton Number5button=NewJButton ("5");      Number5button.addactionlistener (insert); Number5button.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Number5button); JButton Number6button=NewJButton ("6");      Number6button.addactionlistener (insert); Number6button.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Number6button); JButton Multiplybutton=NewJButton ("*");      Multiplybutton.addactionlistener (command); Multiplybutton.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Multiplybutton); JButton Number3button=NewJButton ("1");      Number3button.addactionlistener (insert); Number3button.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Number3button); JButton Number2button=NewJButton ("2");      Number2button.addactionlistener (insert); Number2button.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Number2button); JButton Number1button=NewJButton ("3");      Number1button.addactionlistener (insert); Number1button.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Number1button); JButton Subtractbutton=NewJButton ("-");      Subtractbutton.addactionlistener (command); Subtractbutton.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Subtractbutton); JButton Number0button=NewJButton ("0");      Number0button.addactionlistener (insert); Number0button.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Number0button); JButton Dotbutton=NewJButton ("."); Dotbutton.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Dotbutton); JButton Equalbutton=NewJButton ("=");      Equalbutton.addactionlistener (command); Equalbutton.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));            Buttonpanel.add (Equalbutton); JButton AddButton=NewJButton ("+");      Addbutton.addactionlistener (command); Addbutton.setfont (NewFont ("Microsoft Jas Black", Font.plain, 15));      Buttonpanel.add (AddButton);  Pack (); }    Private classInsertactionImplementsActionListener { Public voidactionperformed (ActionEvent e) {String input=E.getactioncommand (); String text=Display.gettext (); if(start) {Display.settext (""); Start=false; }          if(Text.startswith (".") {Display.settext ("0" + display.gettext () +input); } Else if(Text.startswith (" -0.") | | Text.startswith ("0.")) {Display.settext (Display.gettext () )+input); } Else if(Text.startswith ("-0")) {Display.settext ("-" +input); } Else if(Text.startswith ("0") {display.settext (input); } Else{Display.settext (Display.gettext ()+input); }      }  }    Private classCommandactionImplementsActionListener { Public voidactionperformed (ActionEvent e) {String command=E.getactioncommand (); if(start) {if(Command.equals ("-") {display.settext (command); Start=false; } Else{Lastcommand=command; }          } Else{Calculate (double.parsedouble (Display.gettext ())); Lastcommand=command; Start=true; }      }  }     Public voidCalculateDoublex) {Charoperator = Lastcommand.charat (0); Switch(operator) { Case+: Result+=x;  Break;  Case‘-‘: Result-=x;  Break;  Case‘*‘: Result*=x;  Break;  Case‘/‘: Result/=x;  Break;  Case=: Result=x;  Break; } display.settext ("" +result); }}

Java Implementation simple Calculator function