扫二维码与项目经理沟通
我们在微信上24小时期待你的声音
解答本文疑问/技术咨询/运营咨询/技术建议/互联网交流
表1. CheckerDrag.java
成都创新互联是网站建设专家,致力于互联网品牌建设与网络营销,专业领域包括网站设计制作、成都网站设计、电商网站制作开发、成都微信小程序、微信营销、系统平台开发,与其他网站设计及系统开发公司不同,我们的整合解决方案结合了恒基网络品牌建设经验和互联网整合营销的理念,并将策略和执行紧密结合,且不断评估并优化我们的方案,为客户提供全方位的互联网品牌整合方案!
// CheckerDrag.javaimport java.awt.*;import java.awt.event.*;public class CheckerDrag extends java.applet.Applet{ // Dimension of checkerboard square. // 棋盘上每个小方格的尺寸 final static int SQUAREDIM = 40; // Dimension of checkerboard -- includes black outline. // 棋盘的尺寸 – 包括黑色的轮廓线 final static int BOARDDIM = 8 * SQUAREDIM + 2; // Dimension of checker -- 3/4 the dimension of a square. // 棋子的尺寸 – 方格尺寸的3/4 final static int CHECKERDIM = 3 * SQUAREDIM / 4; // Square colors are dark green or white. // 方格的颜色为深绿色或者白色 final static Color darkGreen = new Color (0, 128, 0); // Dragging flag -- set to true when user presses mouse button over checker // and cleared to false when user releases mouse button. // 拖动标记 --当用户在棋子上按下鼠标按键时设为true, // 释放鼠标按键时设为false boolean inDrag = false; // Left coordinate of checkerboard's upper-left corner. // 棋盘左上角的左方向坐标 int boardx; // Top coordinate of checkerboard's upper-left corner. //棋盘左上角的上方向坐标 int boardy; // Left coordinate of checker rectangle origin (upper-left corner). // 棋子矩形原点(左上角)的左方向坐标 int ox; // Top coordinate of checker rectangle origin (upper-left corner). // 棋子矩形原点(左上角)的上方向坐标 int oy; // Left displacement between mouse coordinates at time of press and checker // rectangle origin. // 在按键时的鼠标坐标与棋子矩形原点之间的左方向位移 int relx; // Top displacement between mouse coordinates at time of press and checker // rectangle origin. // 在按键时的鼠标坐标与棋子矩形原点之间的上方向位移 int rely; // Width of applet drawing area. // applet绘图区域的宽度 int width; // Height of applet drawing area. // applet绘图区域的高度 int height; // Image buffer. // 图像缓冲 Image imBuffer; // Graphics context associated with image buffer. // 图像缓冲相关联的图形背景 Graphics imG; public void init () { // Obtain the size of the applet's drawing area. // 获取applet绘图区域的尺寸 width = getSize ().width; height = getSize ().height; // Create image buffer. // 创建图像缓冲 imBuffer = createImage (width, height); // Retrieve graphics context associated with image buffer. // 取出图像缓冲相关联的图形背景 imG = imBuffer.getGraphics (); // Initialize checkerboard's origin, so that board is centered. // 初始化棋盘的原点,使棋盘在屏幕上居中 boardx = (width - BOARDDIM) / 2 + 1; boardy = (height - BOARDDIM) / 2 + 1; // Initialize checker's rectangle's starting origin so that checker is // centered in the square located in the top row and second column from // the left. // 初始化棋子矩形的起始原点,使得棋子在第一行左数第二列的方格里居中 ox = boardx + SQUAREDIM + (SQUAREDIM - CHECKERDIM) / 2 + 1; oy = boardy + (SQUAREDIM - CHECKERDIM) / 2 + 1; // Attach a mouse listener to the applet. That listener listens for // mouse-button press and mouse-button release events. // 向applet添加一个用来监听鼠标按键的按下和释放事件的鼠标监听器 addMouseListener (new MouseAdapter () { public void mousePressed (MouseEvent e) { // Obtain mouse coordinates at time of press. // 获取按键时的鼠标坐标 int x = e.getX (); int y = e.getY (); // If mouse is over draggable checker at time // of press (i.e., contains (x, y) returns // true), save distance between current mouse // coordinates and draggable checker origin // (which will always be positive) and set drag // flag to true (to indicate drag in progress). // 在按键时如果鼠标位于可拖动的棋子上方 // (也就是contains (x, y)返回true),则保存当前 // 鼠标坐标与棋子的原点之间的距离(始终为正值)并且 // 将拖动标志设为true(用来表明正处在拖动过程中) if (contains (x, y)) { relx = x - ox; rely = y - oy; inDrag = true; } } boolean contains (int x, int y) { // Calculate center of draggable checker. // 计算棋子的中心位置 int cox = ox + CHECKERDIM / 2; int coy = oy + CHECKERDIM / 2; // Return true if (x, y) locates with bounds // of draggable checker. CHECKERDIM / 2 is the // radius. // 如果(x, y)仍处于棋子范围内则返回true // CHECKERDIM / 2为半径 return (cox - x) * (cox - x) + (coy - y) * (coy - y) CHECKERDIM / 2 * CHECKERDIM / 2; } public void mouseReleased (MouseEvent e) { // When mouse is released, clear inDrag (to // indicate no drag in progress) if inDrag is // already set. // 当鼠标按键被释放时,如果inDrag已经为true, // 则将其置为false(用来表明不在拖动过程中) if (inDrag) inDrag = false; } }); // Attach a mouse motion listener to the applet. That listener listens // for mouse drag events. //向applet添加一个用来监听鼠标拖动事件的鼠标运动监听器 addMouseMotionListener (new MouseMotionAdapter () { public void mouseDragged (MouseEvent e) { if (inDrag) { // Calculate draggable checker's new // origin (the upper-left corner of // the checker rectangle). // 计算棋子新的原点(棋子矩形的左上角) int tmpox = e.getX () - relx; int tmpoy = e.getY () - rely; // If the checker is not being moved // (at least partly) off board, // assign the previously calculated // origin (tmpox, tmpoy) as the // permanent origin (ox, oy), and // redraw the display area (with the // draggable checker at the new // coordinates). // 如果棋子(至少是棋子的一部分)没有被 // 移出棋盘,则将之前计算的原点 // (tmpox, tmpoy)赋值给永久性的原点(ox, oy), // 并且刷新显示区域(此时的棋子已经位于新坐标上) if (tmpox boardx tmpoy boardy tmpox + CHECKERDIM boardx + BOARDDIM tmpoy + CHECKERDIM boardy + BOARDDIM) { ox = tmpox; oy = tmpoy; repaint (); } } } }); } public void paint (Graphics g) { // Paint the checkerboard over which the checker will be dragged. // 在棋子将要被拖动的位置上绘制棋盘 paintCheckerBoard (imG, boardx, boardy); // Paint the checker that will be dragged. // 绘制即将被拖动的棋子 paintChecker (imG, ox, oy); // Draw contents of image buffer. // 绘制图像缓冲的内容 g.drawImage (imBuffer, 0, 0, this); } void paintChecker (Graphics g, int x, int y) { // Set checker shadow color. // 设置棋子阴影的颜色 g.setColor (Color.black); // Paint checker shadow. // 绘制棋子的阴影 g.fillOval (x, y, CHECKERDIM, CHECKERDIM); // Set checker color. // 设置棋子颜色 g.setColor (Color.red); // Paint checker. // 绘制棋子 g.fillOval (x, y, CHECKERDIM - CHECKERDIM / 13, CHECKERDIM - CHECKERDIM / 13); } void paintCheckerBoard (Graphics g, int x, int y) { // Paint checkerboard outline. // 绘制棋盘轮廓线 g.setColor (Color.black); g.drawRect (x, y, 8 * SQUAREDIM + 1, 8 * SQUAREDIM + 1); // Paint checkerboard. // 绘制棋盘 for (int row = 0; row 8; row++) { g.setColor (((row 1) != 0) ? darkGreen : Color.white); for (int col = 0; col 8; col++) { g.fillRect (x + 1 + col * SQUAREDIM, y + 1 + row * SQUAREDIM, SQUAREDIM, SQUAREDIM); g.setColor ((g.getColor () == darkGreen) ? Color.white : darkGreen); } } } // The AWT invokes the update() method in response to the repaint() method // calls that are made as a checker is dragged. The default implementation // of this method, which is inherited from the Container class, clears the // applet's drawing area to the background color prior to calling paint(). // This clearing followed by drawing causes flicker. CheckerDrag overrides // update() to prevent the background from being cleared, which eliminates // the flicker. // AWT调用了update()方法来响应拖动棋子时所调用的repaint()方法。该方法从 // Container类继承的默认实现会在调用paint()之前,将applet的绘图区域清除 // 为背景色,这种绘制之后的清除就导致了闪烁。CheckerDrag重写了update()来 // 防止背景被清除,从而消除了闪烁。 public void update (Graphics g) { paint (g); }}
import java.awt.BorderLayout;
import java.awt.FileDialog;
import java.awt.Font;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.StringSelection;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.border.TitledBorder;
/*因为根据个人的电脑路径可能有所偏差,没有源路径的情况下,设置默认保存路径为D盘根目录下
* 若要选择保存其他地方,可以选择 另存为*/
public class TestDemo extends JFrame {
private static final long serialVersionUID = -5355432125621015300L;
private String url = null;//文件路径
private String str=null;//复制或剪切 的字符串
private StringSelection stringSelection=null;
private Clipboard clipboard=new Clipboard(str);
private Transferable transferable=null;
private DataFlavor flavor=null;
public TestDemo() {
init();
}
private void init() {
setTitle("我的记事本");
setSize(500, 600);
setContentPane(createContentPane());//添加主面板
}
/*创建主面板*/
private JPanel createContentPane() {
JPanel pane = new JPanel(new BorderLayout());
pane.add(BorderLayout.NORTH, createChocePane());//添加菜单栏
pane.add(createAreaPane());//添加文本编辑区域
return pane;
}
/*创建菜单栏,以及实现功能*/
private JPanel createChocePane() {
JPanel pane = new JPanel();
JMenuBar menuBar1 = new JMenuBar();
JMenu menu = new JMenu("文件");
menuBar1.add(menu);
JMenuItem menuIt1 = new JMenuItem("新建");
JMenuItem menuIt2 = new JMenuItem("打开");
JMenuItem menuIt3 = new JMenuItem("保存");
JMenuItem menuIt4 = new JMenuItem("另存为");
menu.add(menuIt1);
menu.add(menuIt2);
menu.add(menuIt3);
menu.add(menuIt4);
JMenuBar menuBar2 = new JMenuBar();
JMenu menu2 = new JMenu("编辑");
menuBar2.add(menu2);
JMenuItem menuIt5 = new JMenuItem("复制");
JMenuItem menuIt6 = new JMenuItem("剪切");
JMenuItem menuIt7 = new JMenuItem("粘帖");
menu2.add(menuIt5);
menu2.add(menuIt6);
menu2.add(menuIt7);
JMenuBar menuBar3 = new JMenuBar();
JMenu menu3 = new JMenu("帮助");
menuBar3.add(menu3);
JMenuItem menuIt8 = new JMenuItem("关于记事本");
menu3.add(menuIt8);
pane.add(menuBar1);
pane.add(menuBar2);
pane.add(menuBar3);
menuIt1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
testArea.setText(null);
}
});
menuIt2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
final FileDialog fd = new FileDialog(new JFrame(), "查找文件",
FileDialog.LOAD);
fd.setVisible(true);
if (fd.getDirectory() != null fd.getFile() != null) {
testArea.setText(null);
url = fd.getDirectory() + fd.getFile();
try {
BufferedReader in = new BufferedReader(new FileReader(
url));
for (int i = 0;; i++) {
testArea.append(in.readLine());
if (in.read() == -1) {
break;
} else
continue;
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
});
menuIt3.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (url==null) {
url="D:\\新建 文本文档.txt";
}
File f = new File(url);
BufferedWriter out = null;
try {
out = new BufferedWriter(new FileWriter(url));
f.createNewFile();
out.append(testArea.getText());
out.flush();
} catch (IOException e1) {
e1.printStackTrace();
} finally {
try {
out.close();
} catch (IOException e1) {
e1.printStackTrace();
}
}
}
});
menuIt4.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
FileDialog fd = new FileDialog(new JFrame(), "保存文本",
FileDialog.SAVE);
fd.setVisible(true);
if (url!=null) {
File f = new File(url);
BufferedWriter out = null;
try {
f.createNewFile();
out = new BufferedWriter(new FileWriter(url));
out.append(testArea.getText());
out.flush();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
out.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
});
menuIt5.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
str=testArea.getSelectedText();
stringSelection=new StringSelection(str);
clipboard.setContents(stringSelection, null);
}
});
menuIt6.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
str=testArea.getSelectedText();
stringSelection=new StringSelection(str);
clipboard.setContents(stringSelection, null);
int start=testArea.getSelectionStart();
int end=testArea.getSelectionEnd();
testArea.replaceRange( null,start,end);
}
});
menuIt7.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
transferable=clipboard.getContents(this);
flavor=DataFlavor.stringFlavor;
if (transferable.isDataFlavorSupported(flavor)) {
int start=testArea.getSelectionStart();
int end=testArea.getSelectionEnd();
testArea.replaceRange( null,start,end);
int pos=testArea.getCaretPosition();
try {
str=(String)transferable.getTransferData(flavor);
testArea.insert(str, pos);
} catch (UnsupportedFlavorException e1) {
e1.printStackTrace();
} catch (IOException e1) {
e1.printStackTrace();
}
}
}
});
menuIt8.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(null,"功能简单,绝对原创 ");
}
});
return pane;
}
JTextArea testArea;
private JScrollPane createAreaPane() {
JScrollPane pane = new JScrollPane();
pane.setBorder(new TitledBorder("编辑区域"));
testArea = new JTextArea();
testArea.setFont(new Font("宋体", Font.BOLD, 13));
testArea.setLineWrap(true);
pane.getViewport().add(testArea);
return pane;
}
public static void main(String[] args) {
TestDemo td = new TestDemo();
td.setVisible(true);
}
}
1、第一个Swing程序——JFrame窗体
需要注意的是 JFrame窗体在初始设置的时候存在几个问题:
1 窗体默认不可见,需要设置成为可见
2 窗体默认没有大小,需要设置其大小
3 窗体默认不能关闭,需要设置关闭方式
2、JFrame中添加面板、布局方式与控件
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。
import java.util.Scanner;
public class test {
public static void main(String[] args) {
int j = 0;// 从0米开始跑
Scanner in = new Scanner(System.in);
while(true) {
System.out.println("你跑了多少米?");
j = in.nextInt();
System.out.println("口渴吗?请输入(yes or no)");
String thirst = in.next();
if (j 400) {
if (!thirst.equals("yes")) {
System.out.println("好吧,那你继续跑吧!");
continue; // 不喝水,继续跑
} else {
System.out.println("过来喝水吧");
}
break;
}
else{
continue;
}
}
}
}
谢谢采纳
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
我们在微信上24小时期待你的声音
解答本文疑问/技术咨询/运营咨询/技术建议/互联网交流