「java案例源代码」Java开源代码
本篇文章给大家谈谈java案例源代码，以及Java开源代码对应的知识点，希望对各位有所帮助，不要忘了收藏本站喔。
本文目录一览：
求JAVA源代码
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class GradeStatistic {
public static void main(String[] args) {
GradeStatistic gs = new GradeStatistic();
ListMark list = new ArrayListMark();
float sum = 0;
while(true){
Scanner sc = new Scanner(System.in);
System.out.print("Please input student name: ");
String name = sc.nextLine();
if(name.equals("end")){
break;
}
System.out.print("Please input student score: ");
float score = sc.nextFloat();
sum += score;
list.add(gs.new Mark(name, score));
}
float max = list.get(0).getScore();
float min = list.get(0).getScore();
for(Mark mark: list){
if(max mark.getScore()){
max = mark.getScore();
}
if(min mark.getScore()){
min = mark.getScore();
}
}
float average = sum / list.size();
System.out.println("Average is: " + average);
System.out.println("Max is: " + max);
System.out.println("Min is: " + min);
}
private class Mark{
private String name;
private float score;
public Mark(String name, float score){
this.name = name;
this.score = score;
}
public String getName() {
return name;
}
public float getScore() {
return score;
}
}
}
----------------------
Please input student name: Zhang san
Please input student score: 100
Please input student name: Li Si
Please input student score: 91
Please input student name: Ec
Please input student score: 35
Please input student name: ma qi
Please input student score: 67
Please input student name: end
Average is: 73.25
Max is: 100.0
Min is: 35.0
帮忙给一个java菜单栏例子的源代码
给你个小例子，已经添加注释了。自己运行下看看效果，满意的话记得结贴子！
import java.awt.BorderLayout;
import java.awt.CheckboxMenuItem;
import java.awt.Frame;
import java.awt.Menu;
import java.awt.MenuBar;
import java.awt.MenuItem;
import java.awt.TextArea;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
public class TestMenu extends Frame implements ActionListener{
TextArea ta; //文本区
MenuBar mb; //MenuBar 类封装绑定到框架的菜单栏的
Menu mnFile,mnEdit,mnFormat,mnHelp; //从菜单栏部署的下拉式菜单组件
MenuItem miNew,miOpen,miSave,miSaveAs,miExit,miFont; //菜单中的所有项必须属于类 MenuItem 或其子类之一
CheckboxMenuItem miBinary; //一个可包括在菜单中的复选框
public TestMenu(){
super("记事本"); //调用父类构造方法
ta = new TextArea("",20,20); //新建文本区，第一个参数是默认文本，第二个参数是行数，第三个是列数
/*
* BorderLayout边框布局
* 添加文本区到Frame，BorderLayout.CENTER是居中位置
* */
add(ta,BorderLayout.CENTER);
mb = new MenuBar(); //创建菜单栏对象
/*
* 创建菜单，指定菜单名
* */
mnFile= new Menu("文件");
mnEdit= new Menu("编辑");
mnFormat= new Menu("格式");
mnHelp= new Menu("帮助");
/*
* 创建子菜单，并指定名称
* */
miNew= new MenuItem("新建");
miOpen= new MenuItem("打开");
miSave= new MenuItem("保存");
miSaveAs= new MenuItem("另存为");
miExit= new MenuItem("退出");
miExit.addActionListener(this); //为退出菜单添加监听
/*
* 添加上面创建的子菜单到文件菜单下
* */
mnFile.add(miNew);
mnFile.add(miOpen);
mnFile.add(miSave);
mnFile.add(miSaveAs);
mnFile.addSeparator(); //将一个分隔线或连字符添加到菜单的当前位置
mnFile.add(miExit);
miBinary= new CheckboxMenuItem("二进制"); //创建在复选框的子菜单
miFont= new MenuItem("字体"); //创建子菜单
/*
* 添加miBinary、miFont两个子菜单到mnFormat（格式）下
* */
mnFormat.add(miBinary);
mnFormat.add(miFont);
/*
* 将文件、编辑、格式、帮助添加到菜单栏
* */
mb.add(mnFile);
mb.add(mnEdit);
mb.add(mnFormat);
mb.add(mnHelp);
setMenuBar(mb); //添加菜单栏到Frame
/*
* 关闭窗口时，关闭运行成语
* */
addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(0);
}
});
}
public static void main(String args[]){
TestMenu tm=new TestMenu();
tm.setSize(300,200); //设置窗体的宽、高
tm.setLocation(300,100); //将组件移到新位置Component类方法
tm.setVisible(true); //设置显示窗体，true为显示，false为隐藏
}
/**
* 监听事件，实现ActionListener接口的actionPerformed方法
*/
public void actionPerformed(ActionEvent e){
String s = e.getActionCommand(); //获取选中菜单的名称
System.out.println(s);
if(s.equals("退出")){
System.exit(0); //停止运行程序
}
}
}
用java编写的有输入输出流源代码
/**
* 读写指定文件或者读写指定某一个文件夹下的全部文件(不包括文件夹)
* @throws Exception
*/
public static void moveFile() throws Exception {
Scanner scan = new Scanner(System.in);
System.out.println("请输入源路径：");//输入源文件地址，可以是文件夹，可以是具体某个文件
String uDisk = scan.nextLine();
File file = new File(uDisk);//获得读取文件
if ((file.exists())) {//当文件存在
System.out.println("请输入目标路径：");//文件复制目标路径
String targetFolder = scan.nextLine();
File target = new File(targetFolder);//获得写入文件
if (!target.exists()) {
if (!target.mkdir()) {
throw new Exception("创建目标目录失败");
}
} else if (!target.isDirectory()) {
throw new Exception("与目标目录同名的文件已经存在");
}
File[] temp = null;
if(file.listFiles()==null || file.listFiles().length=0){
temp=new File[]{file};//输入的源路径指定文件，将文件添加到文件数组中
}else{
temp = file.listFiles();//如果输入的源路径是文件夹，则获取文件夹下文件的个数
}
if ((temp != null) (temp.length 0)) {//文件数组temp有值
int i = 0;
for (int length = temp.length; i length; i++) {//循环文件数组
if (!temp[i].isDirectory()) {
String fileName = temp[i].getName();
File t = new File(targetFolder + File.separator
+ fileName);//创建输出文件
if (!t.createNewFile()) {
throw new Exception("创建输出文件失败");
}
FileOutputStream out = new FileOutputStream(t);//创建文件输出流
FileInputStream in = new FileInputStream(temp[i]);//创建文件输入流
byte[] buffer = new byte[256];
while (in.read(buffer) 0) {//循环输入流，直到输入流无数据
out.write(buffer);//写入文件
}
}
}
}
}
}
调用例子：
public static void main(String[] args) throws Exception {
moveFile();
}
什么是java源代码 怎么查看
你说的java源代码是指编译成的class文件前的java文件。
当我们运行.java文件时，它会被系统编译成.class文件，例如Test.java编译之后就是Test.class，
源文件就是指Test.java文件，
一般部署项目时，有.class文件就可以发布运行了，但是如果想修改这个系统，.class是不能修改的，要有.java文件才能修改
也可以上网去下反编译软件，就是能把.class文件大部分还原成.java文件的工具，但不是100%还原，而且如果不是正版的，小心有毒啊，什么的。
求编写一个超级简单的Java的程序源代码
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
class ConstructFrame extends JFrame
{
private static final long serialVersionUID = 1L;
String value1="",result,value2="";
int flag=0,fix=0,sum=1;
Boolean happy;
JTextField text=new JTextField(30);
int flagsum=0;
Container c=getContentPane();
JButton buttonx;
ConstructFrame()
{ super("计算器");
c.setLayout(null);
c.setBackground(Color.blue);
this.setSize(400, 400);
c.add(text);
text.setHorizontalAlignment(JTextField.RIGHT);
final JButton buttonx=new JButton("BackSpace");
c.add(buttonx);
buttonx.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
int count=0;
String temp;
if(flag==0)
{
count=value1.length();
if(count!=1)
temp=value1.substring(0, count-1);
else
temp="0";
value1=temp;
}
else
{
count=value2.length();
if(count!=1)
temp=value2.substring(0, count-1);
else
temp="0";
value2=temp;
}
text.setText(temp);
}
});
final JButton buttony=new JButton("CE");
c.add(buttony);
buttony.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
value1="";
value2="";
flag=0;
text.setText("0");
}
});
final JButton button1=new JButton("1");
c.add(button1);
button1.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
String temp;
if(flag==0)
{
value1=value1+1;
temp=value1;
}
else
{
value2=value2+1;
temp=value2;
}
text.setText(temp);
}
});
final JButton button2=new JButton(" 2 ");
c.add(button2);
button2.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
String temp;
if(flag==0)
{
value1=value1+2;
temp=value1;
}
else
{
value2=value2+2;
temp=value2;
}
text.setText(temp);
}
});
final JButton button3=new JButton("3");
c.add(button3);
button3.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
String temp;
if(flag==0)
{
value1=value1+3;
temp=value1;
}
else
{
value2=value2+3;
temp=value2;
}
text.setText(temp);
}
});
final JButton button4=new JButton("4");
c.add(button4);
button4.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
String temp;
if(flag==0)
{
value1=value1+4;
temp=value1;
}
else
{
value2=value2+4;
temp=value2;
}
text.setText(temp);
}
});
final JButton button5=new JButton("5");
c.add(button5);
button5.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
String temp;
if(flag==0)
{
value1=value1+5;
temp=value1;
}
else
{
value2=value2+5;
temp=value2;
}
text.setText(temp);
}
});
final JButton button6=new JButton("6");
c.add(button6);
button6.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
String temp;
if(flag==0)
{
value1=value1+6;
temp=value1;
}
else
{
value2=value2+6;
temp=value2;
}
text.setText(temp);
}
});
final JButton button7=new JButton("7");
c.add(button7);
button7.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
String temp;
if(flag==0)
{
value1=value1+7;
temp=value1;
}
else
{
value2=value2+7;
temp=value2;
}
text.setText(temp);
}
});
final JButton button8=new JButton("8");
c.add(button8);
button8.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
String temp;
if(flag==0)
{
value1=value1+8;
temp=value1;
}
else
{
value2=value2+8;
temp=value2;
}
text.setText(temp);
}
});
final JButton button9=new JButton("9");
c.add(button9);
button9.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
String temp;
if(flag==0)
{
value1=value1+9;
temp=value1;
}
else
{
value2=value2+9;
temp=value2;
}
text.setText(temp);
}
});
final JButton button0=new JButton("0");
c.add(button0);
button0.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
String temp;
if(flag==0)
{
value1=value1+0;
temp=value1;
}
else
{
value2=value2+0;
temp=value2;
}
text.setText(temp);
}
});
final JButton buttonadd=new JButton(" + ");
c.add(buttonadd);
buttonadd.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
flag=1;
fix=1;
flagsum=0;
}
});
final JButton buttonsubtract=new JButton(" - ");
c.add(buttonsubtract);
buttonsubtract.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
flag=1;
fix=2;
flagsum=0;
}
});
final JButton buttoncheng=new JButton(" * ");
c.add(buttoncheng);
buttoncheng.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
flag=1;
fix=3;
flagsum=0;
}
});
final JButton buttonchu=new JButton(" / ");
c.add(buttonchu);
buttonchu.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
flag=1;
flagsum=0;
fix=4;
}
});
final JButton buttonequal=new JButton(" = ");
c.add(buttonequal);
buttonequal.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
double temp1,temp2;
double temp=0;
flagsum=0;
temp1=Double.parseDouble(value1);
temp2=Double.parseDouble(value2);
flag=0;
switch(fix)
{
case 1: temp=temp1+temp2;break;
case 2: temp=temp1-temp2;break;
case 3: temp=temp1*temp2;break;
case 4: temp=temp1/temp2;break;
}
result=Double.valueOf(temp).toString();
value1=result;
value2="";
flag=1;
text.setText(result);
}
});
final JButton buttonpoint=new JButton(".");
c.add(buttonpoint);
buttonpoint.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{ if(flagsum==0)
{
String temp;
if(flag==0 )
{
value1=value1+".";
temp=value1;
}
else
{
value2=value2+".";
temp=value2;
}
flagsum=1;
text.setText(temp);
}
}
});
JButton buttonz=new JButton("Start");
c.add(buttonz);
buttonz.addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{ if(sum%2==1)
{
happy=true;
text.setText("0.");
flag=0;
}
else
{
happy=false;
value1="";
value2="";
text.setText("");
}
text.setEnabled(happy);
button1.setEnabled(happy);
button2.setEnabled(happy);
button3.setEnabled(happy);
button4.setEnabled(happy);
button5.setEnabled(happy);
button6.setEnabled(happy);
button7.setEnabled(happy);
button8.setEnabled(happy);
button9.setEnabled(happy);
button0.setEnabled(happy);
buttonx.setEnabled(happy);
buttony.setEnabled(happy);
buttonadd.setEnabled(happy);
buttonsubtract.setEnabled(happy);
buttonpoint.setEnabled(happy);
buttonequal.setEnabled(happy);
buttoncheng.setEnabled(happy);
buttonchu.setEnabled(happy);
sum++;
}
});
button1.setEnabled(false);
button2.setEnabled(false);
button3.setEnabled(false);
button4.setEnabled(false);
button5.setEnabled(false);
button6.setEnabled(false);
button7.setEnabled(false);
button8.setEnabled(false);
button9.setEnabled(false);
button0.setEnabled(false);
buttonx.setEnabled(false);
buttony.setEnabled(false);
buttonadd.setEnabled(false);
buttonsubtract.setEnabled(false);
buttonpoint.setEnabled(false);
buttonequal.setEnabled(false);
buttoncheng.setEnabled(false);
buttonchu.setEnabled(false);
text.setEnabled(false);
text.setBounds(20, 20, 200, 40);
buttonx.setBounds(20, 60,100, 40);
buttony.setBounds(140, 60,100, 40);
buttonz.setBounds(260, 60,80, 40);
button1.setBounds(20, 120,60, 40);
button2.setBounds(100, 120,60, 40);
button3.setBounds(180, 120,60, 40);
buttonadd.setBounds(260, 120,60, 40);
button4.setBounds(20, 180,60, 40);
button5.setBounds(100, 180,60, 40);
button6.setBounds(180, 180,60, 40);
buttonsubtract.setBounds(260, 180,60, 40);
button7.setBounds(20, 240,60, 40);
button8.setBounds(100, 240,60, 40);
button9.setBounds(180, 240,60, 40);
buttoncheng.setBounds(260,240,60,40);
button0.setBounds(20, 300,60, 40);
buttonpoint.setBounds(100, 300, 60, 40);
buttonequal.setBounds(180,300,60, 40);
buttonchu.setBounds(260, 300,60, 40);
setVisible(true);
}
class MYMouseEvent extends MouseAdapter
{
public void mousePressed(MouseEvent e)
{
value1=e.toString();
text.setText(value1);
}
}
}
class Calutator
{
public static void main(String[] args)
{
new ConstructFrame();
}
}
你自己慢慢的看吧！
关于java案例源代码和Java开源代码的介绍到此就结束了，不知道你从中找到你需要的信息了吗 ？如果你还想了解更多这方面的信息，记得收藏关注本站。
发布于：2022-11-27，除非注明，否则均为原创文章，转载请注明出处。