1．按照封装模式，编写“电费管理类”Manager。包含：
1）2个私有属性：上月电表读数pre，本月电表读数cur。
2）2个构造方法：无参（初始化pre、cur均为0）；2个参数（初始化pre、cur的值）。
3）main方法
package java大二;
import java.util.Scanner;
class Manager{
private Double pre,cue;//pre 上月电表读数，cue本月电表读数
public Manager(){
Double pre,cue;
Scanner sc=new Scanner(System.in);
System.out.print("输入上月电表读数：");
this.pre=sc.nextDouble();
System.out.print("输入本月电表读数：");
this.cue=sc.nextDouble();
// System.out.println("上月电表读数："+this.pre);
// System.out.println("本月电表读数："+this.cue);
System.out.println("本月与上月的表数差:"+(this.cue-this.pre));
}
public Manager(double pre,double cue) {
System.out.println("上月电表读数："+pre);
System.out.println("本月电表读数："+cue);
System.out.println("本月与上月的表数差:"+(cue-pre));
}
}
public class Thefirsthomework {
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println("无参构造方法");
new Manager();
System.out.println("有参构造方法");
new Manager(50,100);
}
}
运行结果：
2. 编码实现如下图所示界面及功能：
package java大二;
import java.awt.*;
import javax.swing.*;
public class Login0window extends JFrame {
public Login0window() {
JFrame jf = new JFrame("登录窗口");//实例化一个JFrame对象
JPanel mban=new JPanel();//面板
JPanel mban1=new JPanel();//面板
JPanel mban2=new JPanel();//面板
JLabel j1 = new JLabel("用户名");
JLabel j2 = new JLabel("密 码");
JTextField jt1 = new JTextField("",20);//文本框
JTextField jt2 = new JTextField("",20);//文本框
JButton jb1 = new JButton("登入");//按钮
JButton jb2 = new JButton("重置");//按钮
JLabel j3= new JLabel(); // 上下行的距离调整
JLabel j4= new JLabel(); // 上下行的距离调整
j3=new JLabel(" ");
j4=new JLabel(" ");
jf.add(mban);
mban.add(j1);
mban.add(jt1);
mban.add(j3);
mban.add(j2);
mban.add(jt2);
mban.add(j4);
mban.add(jb1);
mban.add(jb2);
jf.setBounds(750, 400, 300, 200);
jf.setVisible(true);
}
public static void main(String[] args) {
new Login0window();
}
}
运行结果：
3．按以下要求编写程序：
1）编写Animal接口，接口中声明run( ) 方法
2）定义Bird类和Fish类实现Animal接口
3）编写Bird类和Fish类的测试程序，并调用其中的run( )方法
package java大二;
//1）编写Animal接口，接口中声明run( ) 方法
//2）定义Bird类和Fish类实现Animal接口
//3）编写Bird类和Fish类的测试程序，并调用其中的run( )方法
interface Anima{ //定义接口
public void run(); //定义方法
}
class Bird extends Interface implements Anima{//定义Bird类，该类继承Anima类，并实现run方法接口
public void run() {
System.out.println("这个是Bird实现了Anima接口的方法");
}
public void doanything(){
System.out.println("这是Bird覆盖父类的方法");
}
}
class Fish extends Interface implements Anima{//定义Fish类，该类继承Anima类，并实现run方法接口
public void run() {
System.out.println("这个是Fish实现了Anima接口的方法");
}
public void doanything(){
System.out.println("这是Fish覆盖父类的方法");
}
}
public class Interface{
public void doanything(){//父类中的方法
}
public static void main(String[] args) {
// TODO Auto-generated method stub
new Bird().run();
new Bird().doanything();
new Fish().run();
new Fish().doanything();
}
}
运行结果：
4. 计算器程序
package java大二;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
import javax.swing.text.JTextComponent;
public class calculator extends JFrame implements ActionListener{
private int count=0;
private int sum1=0,sum2=0,sum3=0,sum4=0,sum5=0;
private double dsum = 0.0,k=1;
private int i=1,j=0;;
final JTextField jt=new JTextField(""); //north文本框
//+ 20, - 30,*40,/50 ,. 666 数字判断是否执行了加减乘除和小数
private JButton jb0=new JButton("0"); private JButton jb1=new JButton("1");
private JButton jb2=new JButton("2"); private JButton jb3=new JButton("3");
private JButton jb4=new JButton("4"); private JButton jb5=new JButton("5");
private JButton jb6=new JButton("6"); private JButton jb7=new JButton("7");
private JButton jb8=new JButton("8"); private JButton jb9=new JButton("9");
private JButton jb10=new JButton("清空");private JButton jb11=new JButton("退格");
private JButton jb12=new JButton("."); private JButton jb13=new JButton("=");
private JButton jb14=new JButton("+"); private JButton jb15=new JButton("-");
private JButton jb16=new JButton("*");private JButton jb17=new JButton("/");
public calculator() {
JFrame jf=new JFrame("计算器");//窗口题目
//三个面板，控制按键的位置，分别为北(north),西(west),东(east),l里面放入组件
jt.addActionListener(this);
setLayout(new BorderLayout());//设置为边界布局
Container c=getContentPane();//定义一个容器
JPanel jp1=new JPanel(new GridLayout(1,1));
JPanel jp2=new JPanel(new GridLayout(5,3,1,1));//五行三列
JPanel jp3=new JPanel(new GridLayout(4,1,1,1));//四行一列
//将按钮添加到面板
jp2.add(jb1); jp2.add(jb2); jp2.add(jb3); jp2.add(jb4); jp2.add(jb5);
jp2.add(jb6); jp2.add(jb7); jp2.add(jb8); jp2.add(jb9); jp2.add(jb10);
jp2.add(jb0);jp2.add(jb11); jp2.add(jb12); jp2.add(jb13);jp3.add(jb14);
jp3.add(jb15);jp3.add(jb16);jp3.add(jb17);
jp1.add(jt);
jt.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent arg0) {
jt.setText("事件处理");
}
});
jb0.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
sum1=sum1*10+0;
jt.setText(""+sum1);
}
});
jb1.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
sum1=sum1*10+1;
jt.setText(""+sum1);
}
});
jb2.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
sum1=sum1*10+2;
jt.setText(""+sum1);
}
});
jb3.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
sum1=sum1*10+3;
jt.setText(""+sum1);
}
});
jb4.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
sum1=sum1*10+4;
jt.setText(""+sum1);
}
});
jb5.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
sum1=sum1*10+5;
jt.setText(""+sum1);
}
});
jb6.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
sum1=sum1*10+6;
jt.setText(""+sum1);
}
});
jb7.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
sum1=sum1*10+7;
jt.setText(""+sum1);
}
});
jb8.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
sum1=sum1*10+8;
jt.setText(""+sum1);
}
});
jb9.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
sum1=sum1*10+9;
jt.setText(""+sum1);
}
});
jb10.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
jt.setText("");
count=0;//重新为数组赋值
sum1=0;
sum2=0;
sum3=0;
sum4=0;
jt.requestFocus();
}
});
jb11.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
jt.setText("");
sum1=sum1/10;
jt.requestFocus();
}
});
jb12.addActionListener(new ActionListener(){//未完成小数点
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
sum5=666;
if(sum1==0) {
sum1=0;
jt.setText(sum1+".");
}
else jt.setText(sum1+".");
j=1;
}
});
jb13.addActionListener(new ActionListener(){//=
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
//在此地方添加数组的计算；
if(sum3==20) {//+
sum4=sum1+sum2;
sum2=0;
sum1=sum4;
jt.setText(""+sum4);
}
else if(sum3==30) {//-
sum4=sum2-sum1;
sum2=0;
sum1=sum4;
jt.setText(""+sum4);
}
else if(sum3==40) {//*
sum4=sum1*sum2;
sum2=0;
sum1=sum4;
jt.setText(""+sum4);
}
else if(sum3==50) {///
sum4=sum2/sum1;
sum2=0;
sum1=sum4;
jt.setText(""+sum4);
}
}
});
jb14.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
jt.setText("+");
sum2+=sum1;
sum1=0;
sum3=20;
jt.requestFocus();
}
});
jb15.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
jt.setText("-");
sum2=sum1;
sum1=0;
sum3=30;
}
});
jb16.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
jt.setText("*");
sum2=sum1;
sum1=0;
sum3=40;
}
});
jb17.addActionListener(new ActionListener(){
public void actionPerforme(ActionEvent arg0) {
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
jt.setText("/");
sum2=sum1;
sum1=0;
sum3=50;
}
});
c.add(BorderLayout.NORTH,jp1);
c.add(BorderLayout.WEST,jp2);
c.add(BorderLayout.EAST,jp3);
jf.add(c);
jf.setBounds(750, 300, 242, 280);
jf.setVisible(true);
}
public static void main(String[] args) {
new calculator();
}
public void actionPerformed(ActionEvent e) {
}
}
5. 谈谈你学习了一学期的Java课程后的收获、体会和感想！以及新学期对老师的期待！
在学习了一学期的java课程之后，收获的不仅仅是知识，更是一种在追求知识的一种渴望，没有知识的凝固对于老师提出的问题和作业自己都无法能够准确的回答，所以在之后的学习和工作中，学习是寄于吃饭睡觉之后的一件片刻也不能停息的事情，没有任何一件事情能够赛的过学习。并且在java课程的第一节课所布置的作业中，充分的认识到查询资料熟悉各个知识是非常的重要，否则无法将所学的知识灵活的运用作业与工作当中 。并且在此次的学习中发现了知识的新大陆，但这也许并不是最后一个大陆，但相信崭新的大陆在之后的学习中会展现在我们面前。在新学期里期望新的老师能够在java的课程中带来不一样的学习方法和学习体验，能够在java的道路上越走越远。另外在过了一半的9102年里，大家也要努力加油呀。
