Java小应用程序

Java小应用程序：

package applet;

import java.applet.AudioClip;

import java.awt.BorderLayout;

import java.awt.Graphics;

import java.awt.Image;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.ItemEvent;

import java.awt.event.ItemListener;

import javax.swing.JApplet;

import javax.swing.JButton;

import javax.swing.JComboBox;

import javax.swing.JLabel;

import javax.swing.JOptionPane;

import javax.swing.JPanel;

import javax.swing.JTextField;

public class AppletCalculator extends JApplet implements ItemListener,ActionListener{

//author：王晓勃

//学号：100102060122

//定义程序变量和对象

JLabel name,id,result;

JTextField text1,text2;

JTextField number1,number2,number3;

double nb1,nb2,nb3;

JComboBox jcstyle; //列表框对象

String[] style = new String[]{"+","-","*","/","%","1/x","sqrt"};

AudioClip au; //音乐文件对象

Image img;

JButton start = new JButton("播放");

JButton stop = new JButton("停止");

JButton jbloop = new JButton("循环");

JButton count = new JButton("计算");

JButton mc = new JButton("清空");

//初始化init（）

public void init(){

//初始化对象

img = getImage(getCodeBase(),"1.jpg");

JPanel jp1 = new JPanel(); //定义面板jp1

name = new JLabel("姓名：");

id = new JLabel("学号：");

text1 = new JTextField("王晓勃",10);

text1.setHorizontalAlignment(JTextField.CENTER); //设置文本对齐方式

text1.setEnabled(false); //设置文本框不可编辑

text2 = new JTextField("100102060122",10);

text2.setHorizontalAlignment(JTextField.CENTER);

text2.setEnabled(false);

//把组件加入面板

jp1.add(name);

jp1.add(text1);

jp1.add(id);

jp1.add(text2);

//定义面板jp2

JPanel jp2 = new JPanel();

number1 = new JTextField("",5);

number2 = new JTextField("",5);

number3 = new JTextField("",5);

number1.setHorizontalAlignment(JTextField.RIGHT);

number2.setHorizontalAlignment(JTextField.RIGHT);

number3.setHorizontalAlignment(JTextField.RIGHT);

result = new JLabel("=");

jcstyle = new JComboBox(style); //为列表框添加选项数组

//添加事件监听器

count.addActionListener(this);

mc.addActionListener(this);

jcstyle.addItemListener(this);

jp2.add(number1);

jp2.add(jcstyle);

jp2.add(number2);

jp2.add(result);

jp2.add(number3);

jp2.add(count);

jp2.add(mc);

//定义面板jp3

JPanel jp3 = new JPanel();

au = getAudioClip(getCodeBase(),"nan.wav");

//添加事件监听器

start.addActionListener(this);

stop.addActionListener(this);

jbloop.addActionListener(this);

jp3.add(start);

jp3.add(jbloop);

jp3.add(stop);

//设置布局管理器

setLayout(new BorderLayout());

add(BorderLayout.NORTH,jp1);

add(BorderLayout.CENTER,jp2);

add(BorderLayout.SOUTH,jp3);

setSize(500,200);

}

//JComboBox事件处理函数

public void itemStateChanged(ItemEvent e){

if(e.getItem()=="1/x"){

number2.setText("");

number2.setEditable(false);

}

if(e.getItem()=="sqrt"){

number2.setText("");

number2.setEditable(false);

}

if(e.getItem()=="+"){

number2.setEditable(true);

}

if(e.getItem()=="-"){

number2.setEditable(true);

}

if(e.getItem()=="*"){

number2.setEditable(true);

}

if(e.getItem()=="/"){

number2.setEditable(true);

}

if(e.getItem()=="%"){

number2.setEditable(true);

}

//其他事件处理函数

public void actionPerformed(ActionEvent e){

JButton b = (JButton)e.getSource();

if(b.equals(start))

{

au.play();

}

if(b.equals(jbloop)){

au.loop();

}

if(b.equals(stop)){

au.stop();

}

if(b.equals(mc)){

number1.setText("");

number2.setText("");

number3.setText("");

}

if(b.equals(count)){

try{

if(jcstyle.getSelectedItem()=="+"){