java经典案例

请定义一个交通工具(Vehicle)的类，其中有:
属性：速度(speed)，体积(size)等等
方法：移动(move())，设置速度(setSpeed(int speed))，加速speedUp(),减速speedDown()等等.
最后在测试类Vehicle中的main()中实例化一个交通工具对象，并通过方法给它初始化speed,size的值，并且通过打印出来。另外，调用加速，减速的方法对速度进行改变。






public class Vehicle
{
private String name;
private String brand;
private String color;
private int number;

public Vehicle(String name;String brand;String color;String number)
{
https://www.360docs.net/doc/d311429669.html,=name;
this.brand=brand;
this.color=color;
this.number=number;
}

public String getName()
{
return name;
}

public String getBrand()
{
return brand;
}

public String getColor()
{
return color;
}

public String getNumber()
{
return number;
}

public void setName(String name)
{
https://www.360docs.net/doc/d311429669.html,=name;
}

public void setBrand(String brand)
{
this.brand=brand;
}

public void setcColor(String color)
{
this.color=color;
}

public void setNumber(String number)
{
this.number=number;
}

public void jiasu()
{
System.out.println("加速！");
}
public void jiansu()
{
System.out.println("减速！");
}
public void move()
{
System.out.println("移动！");
}
public void stop()
{
System.out.println("停止！");
}

public void toString(){
System.out.println("名字"+getName()+"品牌"+getBrand()+"颜色"+getColor+"车牌号"+getNumber());
}

}


class Truck extends Vehicle
{
private int speed;

public Vehicle(String name;String brand;String color;String number,int speed)
{
super(name;brand;color;number);
this.speed=speed;
}

public int getSpeed()
{
return speed;
}

public void setSpeed(int speed)
{
this.speed=speed;
}

public void move()
{
System.out.println("移动！");
}
public void stop()
{
System.out.println("停止！");
}

public void toString(){
System.out.println("名字"+getName()+"品牌"+getBrand()+"颜色"+getColor+"车牌号"+getNumber()+"车速"+getSpeed());
}

public static void main(String args[])
{
Vehicle v = new Vehicle("名字","品牌","颜色","车牌号");
Truck t = new Truck("名字","品牌","颜色","车牌号",60);
v.toString();
t.toString();
}
}

















编写Java程序，模拟简单的计算器。
定义名为Number的类，其中有两个整型数据成员n1和n2，应声明为私有。编写构造方法，赋予n1和n2初始值，再为该类定义加（addition）、减（subtration）、乘（multiplication）、除（division）等公有成员方法，分别对两个成员变量执行加、减、乘、除的运算。
在main方法中创建Number类的对象，调用各个方法，并显示计算结果。
















J

ava计算器 源代码：

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

/**********************Java计算器 主类*********************/
public class SunnyCalculator implements ActionListener {
JFrame f;
JMenu mEdit;
JMenu mView;
JMenu mHelp;
JMenuItem mCopy;
JMenuItem mPaste;
JTextField tResult;
JButton bNumber;
JButton bOperator;
JButton bOther;
JButton bM;
boolean isDouble=false;//是否为实数
int opFlag=-1;
static double t1=0,t2=0,t3=0,result=0;
static int opflag1=-1,opflag2=-1,flag=0,resflag=1;
int preOp,currentOp=0;//标准位
double op1=0,op2=0;//操作数
double n3;
StringBuffer buf=new StringBuffer(20);
StringBuffer copyBoard=new StringBuffer(20);//剪贴板
StringBuffer memory=new StringBuffer(20);//M系列
StringBuffer str=new StringBuffer();
//Java计算器 构造器
public SunnyCalculator()
{
f = new JFrame("Sunny计算器_杨梅树的盔甲");
Container contentPane = f.getContentPane();
/**************************Java计算器 菜单的创建*****************************/
JMenuBar mBar = new JMenuBar();
mBar.setOpaque(true);
mEdit = new JMenu("编辑(E)");
mEdit.setMnemonic(KeyEvent.VK_E);
mCopy = new JMenuItem("复制(C)");
mEdit.add(mCopy);
mPaste = new JMenuItem("粘贴(P)");
mEdit.add(mPaste);
mView = new JMenu("查看(V)");
mView.setMnemonic(KeyEvent.VK_V);
mView.add(new JMenuItem("标准型"));
mView.add(new JMenuItem("科学型"));
mView.addSeparator();
mView.add(new JMenuItem("查看分组"));
mHelp = new JMenu("帮助(H)");
mHelp.setMnemonic(KeyEvent.VK_H);
mHelp.add(new JMenuItem("帮助主题"));
mHelp.addSeparator();
mHelp.add(new JMenuItem("关于计算器"));
mBar.add(mEdit);
mBar.add(mView);
mBar.add(mHelp);
f.setJMenuBar(mBar);
contentPane.setLayout(new BorderLayout());
JPanel pTop = new JPanel();
tResult = new JTextField("0.",26);
tResult.setHorizontalAlignment(JTextField.RIGHT);
tResult.setEditable(false);
pTop.add(tResult);
contentPane.add(pTop,BorderLayout.NORTH);
JPanel pBottom = new JPanel();
pBottom.setLayout(new BorderLayout());
JPanel pLeft = new JPanel();
pLeft.setLayout(new GridLayout(5,1,3,3));
bM = new JButton(" ");
bM.setEnabled(false);
pLeft.add(bM);

/*************************Java计算器 功能键定义***************************/
bOther = new JButton("MC");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
bOther.setMargin(new Insets(3,2,3,2));
pLeft.add(bOther);

bOther = new JButton("MR");
bOther.addA

ctionListener(this);
bOther.setForeground(Color.red);
bOther.setMargin(new Insets(3,2,3,2));
pLeft.add(bOther);

bOther = new JButton("MS");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
bOther.setMargin(new Insets(3,2,3,2));
pLeft.add(bOther);

bOther = new JButton("M+");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
bOther.setMargin(new Insets(3,2,3,2));
pLeft.add(bOther);

pBottom.add(pLeft,BorderLayout.WEST);
JPanel pRight = new JPanel();
pRight.setLayout(new BorderLayout());
JPanel pUp = new JPanel();
pUp.setLayout(new GridLayout(1,3,3,0));

bOther = new JButton("BackSpace");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
bOther.setMargin(new Insets(3,0,3,5));
pUp.add(bOther);

bOther = new JButton("CE");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
pUp.add(bOther);

bOther = new JButton("C");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
pUp.add(bOther);

/***************************Java计算器 数字键盘区定义**************************/
JPanel pDown = new JPanel();
pDown.setLayout(new GridLayout(4,5,3,2));
bNumber = new JButton("7");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(new Insets(3,3,3,3));
pDown.add(bNumber);
bNumber = new JButton("8");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(new Insets(3,3,3,3));
pDown.add(bNumber);
bNumber = new JButton("9");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(new Insets(3,3,3,3));
pDown.add(bNumber);
bOperator = new JButton("/");
bOperator.setForeground(Color.red);
bOperator.addActionListener(this);
bOperator.setMargin(new Insets(3,0,3,0));
pDown.add(bOperator);
bOperator = new JButton("sqrt");
bOperator.addActionListener(this);
bOperator.setForeground(Color.red);
bOperator.setMargin(new Insets(3,0,3,0));
pDown.add(bOperator);
bNumber = new JButton("4");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(new Insets(3,3,3,3));
bNumber.setHorizontalTextPosition(JButton.LEFT);
pDown.add(bNumber);
bNumber = new JButton("5");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(new Insets(3,3,3,3));
pDown.add(bNumber);
bNumber = new JButton("6");
bNumber.setForeground(Co

lor.blue);
bNumber.addActionListener(this);
bNumber.setMargin(new Insets(3,3,3,3));
pDown.add(bNumber);
bOperator = new JButton("*");
bOperator.setForeground(Color.red);
bOperator.addActionListener(this);
bOperator.setMargin(new Insets(3,3,3,3));
pDown.add(bOperator);
bOperator = new JButton("%");
bOperator.setForeground(Color.blue);
bOperator.addActionListener(this);
bOperator.setMargin(new Insets(3,3,3,3));
pDown.add(bOperator);
bNumber = new JButton("1");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(new Insets(3,3,3,3));
pDown.add(bNumber);
bNumber = new JButton("2");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(new Insets(3,3,3,3));
pDown.add(bNumber);
bNumber = new JButton("3");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(new Insets(3,3,3,3));
pDown.add(bNumber);
bOperator = new JButton("-");
bOperator.setForeground(Color.red);
bOperator.addActionListener(this);
bOperator.setMargin(new Insets(3,3,3,3));
pDown.add(bOperator);
bOperator = new JButton("1/x");
bOperator.setForeground(Color.blue);
bOperator.addActionListener(this);
pDown.add(bOperator);
bNumber = new JButton("0");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(new Insets(3,3,3,3));
pDown.add(bNumber);
bOperator = new JButton("+/-");
bOperator.setForeground(Color.blue);
bOperator.addActionListener(this);
bOperator.setMargin(new Insets(3,3,3,3));
pDown.add(bOperator);
bOperator = new JButton(".");
bOperator.setForeground(Color.blue);
bOperator.addActionListener(this);
bOperator.setMargin(new Insets(3,3,3,3));
pDown.add(bOperator);
bOperator = new JButton("+");
bOperator.setForeground(Color.blue);
bOperator.addActionListener(this);
bOperator.setMargin(new Insets(3,3,3,3));
pDown.add(bOperator);
bOperator = new JButton("=");
bOperator.setForeground(Color.blue);
bOperator.addActionListener(this);
bOperator.setMargin(new Insets(3,3,3,3));
pDown.add(bOperator);
pRight.add(pUp,BorderLayout.NORTH);
pRight.add(pDown,BorderLayout.SOUTH);
pBottom.add(pRight,BorderLayout.EAST);
contentPane.add(pBottom,BorderLayout.SOUTH);
f.setSize(new Dimension(320,256));
f.setResizable(false);
f.setVisible(true);
f.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)

{
System.exit(0);
}
}
);
}
/************************Java计算器 计算方法区***************************/
public void actionPerformed(ActionEvent e)
{
String s = e.getActionCommand();
if(s.equals("复制(C)"))
{
String temp = tResult.getText().trim();
copyBoard.replace(0, copyBoard.length(), temp);
mPaste.setEnabled(true);
}
else if(s.equals("粘贴(p)"))
{
tResult.setText(copyBoard.toString());
}
else if(s.equals("CE"))
{
//如果是CE则清除文本框
tResult.setText("0.");
}
else if(s.equals("BackSpace"))
{
if(!tResult.getText().trim().equals("0."))
{
//如果文本框中有内容
if(str.length()!=1 && str.length()!=0)
{
tResult.setText(str.delete(str.length()-1,str.length()).toString());
}
else
{
tResult.setText("0.");
str.setLength(0);
}
}
op2 = Double.parseDouble(tResult.getText().trim());
}
else if(s.equals("C"))
{
//如果是C删除当前计算
tResult.setText("0.");
op1 = op2 = 0;
str.replace(0, str.length(), " ");
preOp = currentOp = 0;
}
else if(s.equals("MC"))
{
//如果是MC则清除缓冲区
String temp = "";
memory.replace(0, memory.length(), temp);
bM.setText(" ");
}
else if(s.equals("MR"))
{
//如果按键为MR则恢复缓冲区的数到文本框
tResult.setText(memory.toString());
}
else if(s.equals("MS"))
{
//如果按键为MS则将文本框的数存入缓冲区
String s1 = tResult.getText().trim();
memory.replace(0, memory.length(), s1);
bM.setText("M");
}
else if(s.equals("M+"))
{
//如果按键为MS则将文本框值与缓冲区的数相加但不显示结果
String temp1 = tResult.getText().trim();
double dtemp = Double.parseDouble(temp1);
String temp2 = memory.toString();
dtemp += Double.parseDouble(temp2);
temp1 = String.valueOf(dtemp);
memory.replace(0, memory.length(), temp1);
}
else if(s.equals("1/x"))
{
//如果按键为1/x则将文本框中的数据为它的倒数
String temp = tResult.getText().trim();
double dtemp = Double.parseDouble(temp);
tResult.setText(""+1/dtemp);
}
else if(s.equals("sqrt"))
{
//

如果按键为sqrt则将文本框中的内容求平方根
String temp = tResult.getText().trim();
double dtemp = Double.parseDouble(temp);
tResult.setText(""+Math.sqrt(dtemp));
}
else if(s.equals("+"))
{
str.setLength(0);
if(currentOp==0)
{
preOp = currentOp = 1;
op2 = 0;
tResult.setText(""+op1);
}
else
{
currentOp = preOp;
preOp = 1;
switch(currentOp){
case 1:
op1 += op2;
tResult.setText(""+op1);
break;
case 2:
op1 -= op2;
tResult.setText(""+op1);
break;
case 3:
op1 *= op2;
tResult.setText(""+op1);
break;
case 4:
op1 /= op2;
tResult.setText(""+op1);
break;
}
}
}
else if(s.equals("-")){
str.setLength(0);
if(currentOp==0)
{
preOp=currentOp=2;//op1=op2;op2=0;
tResult.setText(""+op1);
}
else
{
currentOp =preOp;
preOp =2;
switch(currentOp){
case 1:op1=op1+op2;tResult.setText(""+op1);break;
case 2:op1=op1-op2;tResult.setText(""+op1);break;
case 3:op1=op1*op2;tResult.setText(""+op1);break;
case 4:op1=op1/op2;tResult.setText(""+op1);break;
}
}
}
else if(s.equals("*"))//*
{
str.setLength(0);
if(currentOp==0)
{
preOp=currentOp=3;//op1=op2;op2=1;
tResult.setText(""+op1);//op1=op2;
}
else
{
currentOp =preOp;
preOp =3;
switch(currentOp){
case 1:op1=op1+op2;tResult.setText(""+op1);break;
case 2:op1=op1-op2;tResult.setText(""+op1);break;
case 3:op1=op1*op2;tResult.setText(""+op1);break;
case 4:op1=op1/op2;tResult.setText(""+op1);break;
}
}
}
else if(s.equals("/"))// /
{
str.setLength(0);
if(currentOp==0)
{
preOp=currentOp=4;//op2=1;
tResult.setText(""+op1);//op1=op2;
}
else
{
currentOp =preOp;
preOp =4;
switch(currentOp){
case 1:op1=op1+op2;tResult.setText(""+op1);break;
case 2:op1=op1-op2;tResult.setText(""+op1);break;
case 3:op1=op1*op2;tResult.setText(""+op1);break;
case 4:op1=op1/op2;tResult.setT

ext(""+op1);break;
}
}
}
else if(s.equals("="))// =
{
if(currentOp==0)
{
str.setLength(0);
tResult.setText(""+op2);
}
else
{
str.setLength(0);
currentOp =preOp;
switch(currentOp){
case 1:op1=op1+op2;tResult.setText(""+op1);break;
case 2:op1=op1-op2;tResult.setText(""+op1);break;
case 3:op1=op1*op2;tResult.setText(""+op1);break;
case 4:op1=op1/op2;tResult.setText(""+op1);break;
}
currentOp=0;
op2=0;
}
}
else if(s.equals("."))
{
isDouble=true;
if(tResult.getText().trim().indexOf('.')!=-1);
else {
if(tResult.getText().trim().equals("0")) {
str.setLength(0);
tResult.setText((str.append("0"+s)).toString());
}
//else if(tResult.getText().trim().equals("")){}//如果初时显示为空则不做任何操作
else {
tResult.setText((str.append(s)).toString());
}
}
}
else if(s.equals("0"))//如果选择的是"0"这个数字键
{
if(tResult.getText().trim().equals("0.")){}
else{
tResult.setText(str.append(s).toString());
op2=Double.parseDouble(tResult.getText().trim());
}
}
else{
tResult.setText(str.append(s).toString());
op2=Double.parseDouble(tResult.getText().trim());
if(currentOp==0)
op1=op2;
}
}//end actionPerformed
public static void main(String[] args) {
new SunnyCalculator();
}
}








编写Java程序，用于显示人的姓名和年龄。
定义一个人类（Person），该类中应该有两个私有属性，姓名（name）和年龄（age）。定义构造方法，用来初始化数据成员。再定义显示（display）方法，将姓名和年龄打印出来。
在main方法中创建人类的实例，然后将信息显示。


public class Person() {
String name;
int age;
String sex; //或者用int表示:如0表示男 1表示女
List msg = new ArrayList();

person(String name,int age,String sex){
https://www.360docs.net/doc/d311429669.html, = name;
this.age = age;
this.sex = sex;
}

public void add(Person p) {
msg.add(p);
}
public static void main(String[] args) {

}
}






为“无名的粉”写一个类：class WuMingFen 要求：
1.有三个属性：面码:String theMa 粉的分量(两)：int quantity
是否带汤：boolean likeSoup
2.写一个构造方法，以便于简化初始化过程，如：
WuMingFen f1 = new WuMingFen("牛肉

",3,true);
3.重载构造方法，使得初始化过程可以多样化：
WuMingFen f2 = new WuMingFen("牛肉",2);
4.如何使得下列语句构造出来的粉对象是酸辣面码、2两、带汤的？
WuMingFen f3 = new WuMingFen();


public class WuMingFen {
private String theMa;// 面码
private int quantity;// 粉的分量(两)
private boolean likeSoup;// 是否带汤

// 构造出来的粉对象是酸辣面码、2两、带汤的
public WuMingFen() {
this.theMa = "酸辣";
this.quantity = 2;
this.likeSoup = true;
}

public WuMingFen(String theMa, int quantity) {
this.theMa = theMa;
this.quantity = quantity;
this.likeSoup = true;// 给个默认
}

public WuMingFen(String theMa, int quantity, boolean likeSoup) {
this.theMa = theMa;
this.quantity = quantity;
this.likeSoup = likeSoup;
}

public void check() {
System.out.println("面码:" + this.theMa + "\n分量:" + this.quantity
+ "(两)\n带汤:" + this.likeSoup);
}

public static void main(String[] args) {
WuMingFen f1 = new WuMingFen("牛肉", 3, true);
WuMingFen f2 = new WuMingFen("牛肉", 2);
WuMingFen f3 = new WuMingFen();
f1.check();
f2.check();
f3.check();
}
}





定义一个名为Vehicles（交通工具）的基类，该类中应包含String类型的成员属性brand（商标）和color（颜色），还应包含成员方法run（行驶，在控制台显示“我已经开动了”）和showInfo（显示信息，在控制台显示商标和颜色），并编写构造方法初始化其成员属性。
编写Car（小汽车）类继承于Vehicles类，增加int型成员属性seats（座位），还应增加成员方法showCar（在控制台显示小汽车的信息），并编写构造方法。
编写Truck（卡车）类继承于Vehicles类，增加float型成员属性load（载重），还应增加成员方法showTruck（在控制台显示卡车的信息），并编写构造方法。
在main方法中测试以上各类。


public class Vehicles {
private String brand;
private String color;

//构造方法
public Vehicles(String brand, String color) {

this.brand = brand;
this.color = color;
}

public void run() {
System.out.println("我已经开动了");
}

public void showinfo() {
System.out.println("商标： " + brand);
System.out.println("颜色： " + color);
}
}

保存为Vehicles.java


/////////////////////////////////////////////////////////////
public class Car extends Vehicles {

private int seats;
//构造方法
public Car(String brand, String color, int seats) {
super(brand, color);
this.seats = seats;
}

public void showCar() {
super.showinfo();
System.out.println("座位： " + seats + " 个");
}
}

保存为 Car.java
//////////////////////////////////////////////////////////////////////////////
public class Truck extends Vehicles {

private float load;

public Truck(String brand, String color, float load) {

super(brand, color);
this.load = load;
}

public void showTruck() {

super.showinfo();
System.out.println("载重 ：" + load + "吨");
}
}

保存为Truck.java

//////////////////////////////////////////////////////////////////////////////
public class Test {
public static void main(String[] args) {

Vehicles vehicle = new Vehicles("奥迪", "黑色");
vehicle.showinfo();

Car car = new Car("桑塔纳", "红色", 5);
car.showCar();

Truck truck = new Truck("解放", "蓝色", 10);
truck.showTruck();
}
}

保存为 Test.java

把这个四个文件放在一个目录下，
在cmd中输入
javac Test.java
java Test赞同1| 评论