有一篇作業java基礎的（java課後作業）

本文目錄一覽：

• 1、java小白，自學中，我做了一道基礎的java練習題，不知道正確與否，視頻教學中並沒有給出解答，求大神檢查
• 2、JAVA作業
• 3、誰能幫一下我，java選修課的作業，一題兩題都可以，先謝謝了！！
• 4、Java作業求幫助 題一: 編寫一個Java程序，在程序中定義一個PersonA類，定義
• 5、請幫我做一道JAVA的作業題，很簡單的，我是初學者
• 6、一個java的作業！~

java小白，自學中，我做了一道基礎的java練習題，不知道正確與否，視頻教學中並沒有給出解答，求大神檢查

看來你沒有運行過啊！！！

main方法寫錯了，參數丟了

scanner沒有實例化，就是沒有new

scanner方法錯了，in.nextInt（）；

if判斷‘=’是賦值，‘==’才是判斷是否相等，另外不能連等

a==b b==c 應該這樣；

邏輯到是沒錯的，這樣可以實現；如果嵌套的話，可能是讓你將判斷是否大於1000 寫在

else{

if（sum1000）{

}else{

}

}裡面

JAVA作業

4 final

5 方法名稱、返回值、參數簽名

6 public class C extends B implements C

7 class

8 false，true，false

9 private

10 Object

11 編譯時類型與運行時類型不一致，重寫，重載

12 import

13 抽象方法，final修飾或者private修飾

14 aceg

判斷：

1 不一定 protect修飾的 父類與子類在不同包里不能繼承

2 錯

3 錯

4 對

5 錯

6 對

更多JAVA問題，請去ITMUCH，IT木蟲

誰能幫一下我，java選修課的作業，一題兩題都可以，先謝謝了！！

2、類的方法與異常處理：

在一個類的main方法中定義一個長度為8的int型數組，用for循環對數組中的元素1到8的值。隨機產生兩個整數，將這兩個整數作為數組的下標來引用數組中的元素，求出這兩個元素的積，並在屏幕上輸出這兩個元素的值和積。要求在出現數組下標越界時，採用try-catch的方法捕獲異常。

import java.util.Random;

public class SecondTest {

public static void main(String[] args) {

//定義一個長度為8的int型數組

int[] ary = {35, 42, 13, 46, 59, 37, 125, 99};

//用for循環對數組中的元素1到8的值

for(int i= 1; i ary.length;i++){

System.out.print(ary[i] + “\t”);

}

System.out.println();

try{

Random rand = new Random();

//隨機產生兩個整數

int first = rand.nextInt();

int second = rand.nextInt();

//這兩個整數作為數組的下標來引用數組中的元素，求出這兩個元素的積

long mul = ary[first] * ary[second];

//屏幕上輸出這兩個元素的值和積

System.out.println(“積為” + mul);

}catch(ArrayIndexOutOfBoundsException exp){

//出現數組下標越界時，採用try-catch的方法捕獲異常

System.out.println(“數組下標越界! Error!”);

}

}

}

、類與對象的基礎題：

1）編程實現：設計一個類Simple，有三個成員變量，分別為int型、double型和String型，這三個成員變量分別含有各自的get方法和set方法，可以用toString方法顯示這三個成員變量。，

2）聲明測試類：在測試類的main 方法中創建Simple類的對象aSimple,此對象調用set方法分別對對象的各個屬性設置具體的值，然後調用get方法將aSimple的具體的值輸出在屏幕上。

public class TestSimple {//測試類的

public static void main(String[] args) {

//創建Simple類的對象aSimple

Simple aSimple = new Simple();

//set方法分別對對象的各個屬性設置具體的值

aSimple.setIntValue(5);

aSimple.setDoubleValue(123.45D);

aSimple.setStrValue(“string value for simple”);

//get方法將aSimple的具體的值輸出在屏幕上

System.out.println(“int value for simple is: ” + aSimple.getIntValue());

System.out.println(“double value for simple is: ” + aSimple.getDoubleValue());

System.out.println(“String value for simple is: ” + aSimple.getStrValue());

}

}

class Simple{//類Simple

private int intValue;//int型成員變量

private double doubleValue;//double型成員變量

private String strValue;//String型成員變量

//用toString方法顯示這三個成員變量

public String toString(){

return intValue + “, ” + doubleValue + “, ” + strValue;

}

public double getDoubleValue() {

return doubleValue;

}

public void setDoubleValue(double doubleValue) {

this.doubleValue = doubleValue;

}

public int getIntValue() {

return intValue;

}

public void setIntValue(int intValue) {

this.intValue = intValue;

}

public String getStrValue() {

return strValue;

}

public void setStrValue(String strValue) {

this.strValue = strValue;

}

}

Java作業求幫助 題一: 編寫一個Java程序，在程序中定義一個PersonA類，定義

代碼1：extends PersonA

代碼2：s1.setName(“張三”);

代碼3：s1.setDepartment(“計算機系”);

代碼4：System.out.println(s1.getName());

代碼5：System.out.println(s1.getDepartment());

注意，後四句最後的分號別落下了

請幫我做一道JAVA的作業題，很簡單的，我是初學者

package jisuanqi;

import java.awt.BorderLayout;

import java.awt.Dimension;

import javax.swing.JFrame;

import javax.swing.JPanel;

import javax.swing.JButton;

import javax.swing.BorderFactory;

import java.awt.Rectangle;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import javax.swing.JTextField;

import javax.swing.*;

/**

* pTitle: /p

*

* pDescription: /p

*

* pCopyright: Copyright (c) 2007/p

*

* pCompany: /p

*

* @author not attributable

* @version 1.0

*/

public class Jisuan extends JFrame {

JPanel contentPane;

JButton btnmultiply = new JButton();

JButton btn3 = new JButton();

JButton btndivide = new JButton();

JButton btn2 = new JButton();

JButton btn5 = new JButton();

JButton btn0 = new JButton();

JButton btnclear = new JButton();

JButton btnequal = new JButton();

JButton btn1 = new JButton();

JButton btn6 = new JButton();

JButton bntplus = new JButton();

JButton btnminus = new JButton();

JButton btn4 = new JButton();

JButton btn9 = new JButton();

JButton btn8 = new JButton();

JButton btn7 = new JButton();

JPanel jPanel1 = new JPanel();

JTextField txt = new JTextField();

boolean flag=false;

String operand1;

String operand2;

double result;

String action;

public Jisuan() {

try {

setDefaultCloseOperation(EXIT_ON_CLOSE);

jbInit();

} catch (Exception exception) {

exception.printStackTrace();

}

}

/**

* Component initialization.

*

* @throws java.lang.Exception

*/

private void jbInit() throws Exception {

contentPane = (JPanel) getContentPane();

contentPane.setLayout(null);

setSize(new Dimension(300, 400));

setTitle(“Frame Title”);

btnmultiply.setBounds(new Rectangle(227, 322, 42, 35));

btnmultiply.setText(“+”);

btnmultiply.addActionListener(new Jisuan_jButton1_actionAdapter(this));

contentPane.setBorder(BorderFactory.createEtchedBorder());

contentPane.setToolTipText(“”);

btn3.setBounds(new Rectangle(160, 263, 42, 35));

btn3.setText(“3”);

btn3.addActionListener(new Jisuan_btn3_actionAdapter(this));

btndivide.setBounds(new Rectangle(227, 263, 42, 35));

btndivide.setText(“-“);

btndivide.addActionListener(new Jisuan_jButton3_actionAdapter(this));

btn2.setBounds(new Rectangle(93, 263, 42, 35));

btn2.setText(“2”);

btn2.addActionListener(new Jisuan_btn2_actionAdapter(this));

btn5.setBounds(new Rectangle(93, 201, 42, 35));

btn5.setText(“5”);

btn5.addActionListener(new Jisuan_btn5_actionAdapter(this));

btn0.setBounds(new Rectangle(25, 322, 42, 35));

btn0.setText(“0”);

btn0.addActionListener(new Jisuan_btn0_actionAdapter(this));

btnclear.setBounds(new Rectangle(93, 322, 42, 35));

btnclear.setText(“c”);

btnclear.addActionListener(new Jisuan_jButton7_actionAdapter(this));

btnequal.setBounds(new Rectangle(160, 322, 42, 35));

btnequal.setText(“=”);

btnequal.addActionListener(new Jisuan_btnequal_actionAdapter(this));

btn1.setBounds(new Rectangle(25, 263, 42, 35));

btn1.setText(“1”);

btn1.addActionListener(new Jisuan_btn1_actionAdapter(this));

btn6.setBounds(new Rectangle(160, 201, 42, 35));

btn6.setText(“6”);

btn6.addActionListener(new Jisuan_btn6_actionAdapter(this));

bntplus.setBounds(new Rectangle(227, 201, 42, 35));

bntplus.setText(“*”);

bntplus.addActionListener(new Jisuan_btnminus_actionAdapter(this));

btnminus.setBounds(new Rectangle(227, 137, 42, 35));

btnminus.setText(“/”);

btnminus.addActionListener(new Jisuan_bntplus_actionAdapter(this));

btn4.setBounds(new Rectangle(25, 201, 42, 35));

btn4.setText(“4”);

btn4.addActionListener(new Jisuan_btn4_actionAdapter(this));

btn9.setBounds(new Rectangle(160, 137, 42, 35));

btn9.setText(“9”);

btn9.addActionListener(new Jisuan_btn9_actionAdapter(this));

btn8.setBounds(new Rectangle(93, 137, 42, 35));

btn8.setText(“8”);

btn8.addActionListener(new Jisuan_btn8_actionAdapter(this));

btn7.setBounds(new Rectangle(25, 137, 42, 35));

btn7.setText(“7”);

btn7.addActionListener(new Jisuan_btn7_actionAdapter(this));

jPanel1.setBorder(BorderFactory.createEtchedBorder());

jPanel1.setBounds(new Rectangle(13, 128, 270, 244));

txt.setHorizontalAlignment(SwingConstants.RIGHT);

txt.setBounds(new Rectangle(13, 61, 270, 46));

contentPane.add(btndivide);

contentPane.add(btn3);

contentPane.add(btn2);

contentPane.add(btnclear);

contentPane.add(btnmultiply, null);

contentPane.add(btnequal);

contentPane.add(btn1);

contentPane.add(btn0);

contentPane.add(btn5);

contentPane.add(btn6);

contentPane.add(bntplus);

contentPane.add(btn4);

contentPane.add(btn7);

contentPane.add(btn8);

contentPane.add(btn9);

contentPane.add(btnminus);

contentPane.add(jPanel1);

contentPane.add(txt);

}

public void jButton1_actionPerformed(ActionEvent e) {

action=”plus”;

operand1=txt.getText();

txt.setText(“”);

flag=true;

}

public void jButton3_actionPerformed(ActionEvent e) {

action=”minus”;

operand1=txt.getText();

txt.setText(“”);

flag=true;

}

public void btn1_actionPerformed(ActionEvent e) {

if(flag){

txt.setText(btn1.getActionCommand());

flag=false;

}

else{

txt.setText(txt.getText()+btn1.getActionCommand());

}

}

public void btn6_actionPerformed(ActionEvent e) {

if(flag){

txt.setText(btn6.getActionCommand());

flag=false;

}

else{

txt.setText(txt.getText()+btn6.getActionCommand());

}

}

public void btn2_actionPerformed(ActionEvent e) {

if(flag){

txt.setText(btn2.getActionCommand());

flag=false;

}

else{

txt.setText(txt.getText()+btn2.getActionCommand());

}

}

public void btn3_actionPerformed(ActionEvent e) {

if(flag){

txt.setText(btn3.getActionCommand());

flag=false;

}

else{

txt.setText(txt.getText()+btn3.getActionCommand());

}

}

public void btn4_actionPerformed(ActionEvent e) {

if(flag){

txt.setText(btn4.getActionCommand());

flag=false;

}

else{

txt.setText(txt.getText()+btn4.getActionCommand());

}

}

public void btn5_actionPerformed(ActionEvent e) {

if(flag){

txt.setText(btn5.getActionCommand());

flag=false;

}

else{

txt.setText(txt.getText()+btn5.getActionCommand());

}

}

public void btn7_actionPerformed(ActionEvent e) {

if(flag){

txt.setText(btn7.getActionCommand());

flag=false;

}

else{

txt.setText(txt.getText()+btn7.getActionCommand());

}

}

public void btn8_actionPerformed(ActionEvent e) {

if(flag){

txt.setText(btn8.getActionCommand());

flag=false;

}

else{

txt.setText(txt.getText()+btn8.getActionCommand());

}

}

public void btn9_actionPerformed(ActionEvent e) {

if(flag){

txt.setText(btn9.getActionCommand());

flag=false;

}

else{

txt.setText(txt.getText()+btn9.getActionCommand());

}

}

public void btn0_actionPerformed(ActionEvent e) {

if(flag){

txt.setText(btn0.getActionCommand());

flag=false;

}

else{

txt.setText(txt.getText()+btn0.getActionCommand());

}

}

public void jButton7_actionPerformed(ActionEvent e) {

txt.setText(“”);

}

public void bntplus_actionPerformed(ActionEvent e) {

/*

operand1=Integer.parseInt(txt.getText());

action=”plus”;

flag=true;

*/

action=”divide”;

operand1=txt.getText();

txt.setText(“”);

flag=true;

}

public void btnminus_actionPerformed(ActionEvent e) {

action=”multiply”;

operand1=txt.getText();

txt.setText(“”);

flag=true;

}

public void btnequal_actionPerformed(ActionEvent e) {

double digit1;

double digit2;

operand2=txt.getText();

if(flag==false){

if(action.equals(“divide”)){

digit1=Integer.parseInt(operand1);

digit2=Integer.parseInt(operand2);

result=digit1 / digit2;

txt.setText(new Double(result).toString());

flag=true;

}else if(action.equals(“plus”)){

digit1=Integer.parseInt(operand1);

digit2=Integer.parseInt(operand2);

result=digit1 + digit2;

txt.setText(“”+(int)result);

flag=true;

}else if(action.equals(“multiply”)){

digit1=Integer.parseInt(operand1);

digit2=Integer.parseInt(operand2);

result=digit1 * digit2;

txt.setText(“”+(int)result);

flag=true;

}else if(action.equals(“minus”)){

digit1=Integer.parseInt(operand1);

digit2=Integer.parseInt(operand2);

result=digit1-digit2;

txt.setText(“”+(int)result);

flag=true;

}

}

}

}

class Jisuan_btnminus_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_btnminus_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.btnminus_actionPerformed(e);

}

}

class Jisuan_bntplus_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_bntplus_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.bntplus_actionPerformed(e);

}

}

class Jisuan_jButton7_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_jButton7_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.jButton7_actionPerformed(e);

}

}

class Jisuan_btn0_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_btn0_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.btn0_actionPerformed(e);

}

}

class Jisuan_btn9_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_btn9_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.btn9_actionPerformed(e);

}

}

class Jisuan_btn8_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_btn8_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.btn8_actionPerformed(e);

}

}

class Jisuan_btn7_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_btn7_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.btn7_actionPerformed(e);

}

}

class Jisuan_btn6_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_btn6_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.btn6_actionPerformed(e);

}

}

class Jisuan_btn5_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_btn5_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.btn5_actionPerformed(e);

}

}

class Jisuan_btn4_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_btn4_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.btn4_actionPerformed(e);

}

}

class Jisuan_btn3_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_btn3_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.btn3_actionPerformed(e);

}

}

class Jisuan_btn2_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_btn2_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.btn2_actionPerformed(e);

}

}

class Jisuan_btn1_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_btn1_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.btn1_actionPerformed(e);

}

}

class Jisuan_jButton3_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_jButton3_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.jButton3_actionPerformed(e);

}

}

class Jisuan_jButton1_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_jButton1_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.jButton1_actionPerformed(e);

}

}

class Jisuan_btnequal_actionAdapter implements ActionListener {

private Jisuan adaptee;

Jisuan_btnequal_actionAdapter(Jisuan adaptee) {

this.adaptee = adaptee;

}

public void actionPerformed(ActionEvent e) {

adaptee.btnequal_actionPerformed(e);

}

}

這個是實現的方法，按鈕的名字不一定一樣，最主要是這個要一樣 action=”minus”;

一點都不簡單 很長啊

一個java的作業！~

import java.lang.Math;

//a+bx+cx^2=y

public class func(double a1,double b1,double c1,double x1){

double a=a1;idouble b=b1;double c=c1;double x=x1;idouble y=0;

public void function(double a,double b,double x)

{

if((b^2-4*a*c)0.0)

printf(“沒有實根”);

double x1=-(b/2a)+Math.sqrt(b^2-4*a*c)/2a;

double x2=-(b/2a)-Math.sqrt(b^2-4*a*c)/2a;

printf(“根為x1=%d,x2=%d”,x1,x2);

}