第十五周学习总结
第一部分:理论知识
JAR文件; 应用程序首选项存储; Java Web Start
JAR文件:
1.Java程序的打包:程序编译完成后,程序员将.class文件压缩打包为.jar文件后,GUI界面程序就可以直接双击图标运行。
2.jar文件(Java归档)既可以包含类文件,也可包含诸如图像和声音这些其它类型的文件。
3.JAR文件是压缩的,它使用ZIP压缩格式。
1 jar命令格式: jar {ctxui} [vfm0Me] [jar-file] [manifest-file] [entry-point] [-C dir] files ...
2 Jar命令选项:
– -c 创建一个新的或者空的存档文件并加入文件
– -C 暂时改变到指定的目录
– -e 在清单文件中创建一个条目
– -f 将JAR文件名指定为第二个命令行参数
– -i 为指定的JAR文件产生索引信息
– -m 将一个清单文件(manifest)添加到JAR文件中
– -M 不产生所有项的清单文件(manifest)
– -t 列出存档内容的列表
– -u 更新已存在的JAR文件
– -v 生成详细的输出结果
– -x 解压存档中的命名的(或所有的〕文件
– -0 只存储方式,不用ZIP压缩格式
(1) 创建JAR文件 jar cf jar-file input-file(s) c---want to Create a JAR file. eg:
1) jar cf MenuTest.jar *.class *.gif f---want the output to go to a file rather than to stdout.
2) jar cvf MenuTest.jar *.class *.gif v---Produces verbose output to stdout.
3) jar cvf MenuTest.jar * *---create all contents in current directory.
4) jar cv0f MenuTest.jar * 0---don't want the JAR file to be compressed.
(2) 查看JAR文件 jar tf jar-file t---want to view the Table of contents of the JAR file. eg:
1) jar tvf MenuTest.jar v---Produces verbose output to stdout.
(3) 提取JAR文件 jar xf jar-file [archived-file(s)] x---want to extract files from the JAR archive. eg:
1) jar xf MenuTest.jar copy.gif(仅提取文件copy.gif)
2) jar xf MenuTest.jar alex/copy.gif(仅提取目录alex下的 文件copy.gif)
3) jar xf MenuTest.jar(提取该JAR中的所有文件或目录)
(4) 更新JAR文件 jar uf jar-file input-file(s) u---want to update an existing JAR file. eg:
1) jar uf MenuTest.jar copy.gif
(5) 索引JAR文件 jar i jar-file i---index an existing JAR file. eg:
1) jar i MenuTest.jar
清单文件
每个JAR文件中包含一个用于描述归档特征的清单文件(manifest)。清单文件被命名为MANIFEST.MF,它位于JAR文件的一个特殊的META-INF子目录中。
最小的符合标准的清单文件是很简单的:Manifest-Version:1.0复杂的清单文件包含多个条目,这些条目被分成多个节。第一节被称为主节,作用于整个JAR文件。随后的条目用来指定已命名条目的属性,可以是文件、包或者URL。
清单文件的节与节之间用空行分开,最后一行必须以换行符结束。否则,清单文件将无法被正确地读取。
– 创建一个包含清单的JAR文件,应该运行:
jar cfm MyArchive.jar manifest.mf com/*.class
– 要更新一个已有JAR文件的清单,则需要将增加的部分
放置到一个文本文件中,运行如下命令:
jar ufm MyArchive.jar manifest-additions.mf
运行JAR文件
用户可以通过下面的命令来启动应用程序:
java –jar MyProgram.jar
窗口操作系统,可通过双击JAR文件图标来启动应用程序。
资源
Java中,应用程序使用的类通常需要一些相关的数据文件,这些文件称为资源(Resource)。
–图像和声音文件。
–带有消息字符串和按钮标签的文本文件。
–二进制数据文件,如:描述地图布局的文件。
类加载器知道如何搜索类文件,直到在类路径、存档文件或Web服务器上找到为止。
利用资源机制对于非类文件也可以进行同样操作,具体步骤如下:
– 获得资源的Class对象。
– 如果资源是一个图像或声音文件,那么就需要调用getresource(filename)获得资源的URL位置,然后利用getImage或getAudioClip方法进行读取。
– 如果资源是文本或二进制文件,那么就可以使用getResouceAsStream方法读取文件中的数据。
资源文件可以与类文件放在同一个目录中,也可以将资源文件放在其它子目录中。具体有以下两种方式:
–相对资源名:如data/text/about.txt它会被解释为相对于加载这个资源的类所在的包。
–绝对资源名:如/corejava/title.txt
ResourceTest.java程序演示了资源加载的过程。
编译、创建JAR文件和执行这个程序的命令如下: – javac ResourceTest.java – jar cvfm ResourceTest.jar ResourceTest.mf *.class *.gif *.txt – java –jar ResourceTest.jar
第二部分:实验
1、实验目的与要求
(1) 掌握Java应用程序的打包操作;
(2) 了解应用程序存储配置信息的两种方法;
(3) 掌握基于JNLP协议的java Web Start应用程序的发布方法;
(5) 掌握Java GUI 编程技术。
2、实验内容和步骤
实验1: 导入第13章示例程序,测试程序并进行代码注释。
测试程序1
l 在elipse IDE中调试运行教材585页程序13-1,结合程序运行结果理解程序;
l 将所生成的JAR文件移到另外一个不同的目录中,再运行该归档文件,以便确认程序是从JAR文件中,而不是从当前目录中读取的资源。
l 掌握创建JAR文件的方法;
1 package A; 2 3 import java.awt.*; 4 5 import java.io.*; 6 import java.net.*; 7 import java.util.*; 8 import javax.swing.*; 9 10 /** 11 * @version 1.41 2015-06-12 12 * @author Cay Horstmann 13 */ 14 public class ResourceTest 15 { 16 public static void main(String[] args) 17 { 18 EventQueue.invokeLater(() -> { 19 JFrame frame = new ResourceTestFrame(); 20 frame.setTitle("ResourceTest"); 21 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 22 frame.setVisible(true); 23 }); 24 } 25 } 26 27 /** 28 * A frame that loads image and text resources. 29 */ 30 class ResourceTestFrame extends JFrame 31 { 32 private static final int DEFAULT_WIDTH = 300; 33 private static final int DEFAULT_HEIGHT = 300; 34 35 public ResourceTestFrame() 36 { 37 setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT); 38 URL aboutURL = getClass().getResource("about.gif"); 39 Image img = new ImageIcon(aboutURL).getImage(); 40 setIconImage(img); 41 42 JTextArea textArea = new JTextArea(); 43 InputStream stream = getClass().getResourceAsStream("about.txt"); 44 try (Scanner in = new Scanner(stream, "UTF-8")) 45 { 46 while (in.hasNext()) 47 textArea.append(in.nextLine() + " "); 48 } 49 add(textArea); 50 } 51 }
1 Core Java: Fundamentals 2 10th Edition 3 Cay Horstmann and Gary Cornell 4 Copyright 漏 2016 5 Prentice-Hall
Main-Class: resource.ResourceTest
测试程序2
l 在elipse IDE中调试运行教材583页-584程序13-2,结合程序运行结果理解程序;
l 了解Properties类中常用的方法;
1 package properties; 2 3 import java.awt.EventQueue; 4 import java.awt.event.*; 5 import java.io.*; 6 import java.util.Properties; 7 8 import javax.swing.*; 9 10 /** 11 * 一个测试属性的程序。 程序记住帧的位置、大小和标题 12 * @version 1.01 2015-06-16 13 * @author Cay Horstmann 14 */ 15 public class PropertiesTest 16 { 17 public static void main(String[] args) 18 { 19 EventQueue.invokeLater(() -> { 20 PropertiesFrame frame = new PropertiesFrame(); 21 frame.setVisible(true); 22 }); 23 } 24 } 25 26 /** 27 * 从属性文件和更新恢复位置和大小的框架。退出时的属性。 28 */ 29 class PropertiesFrame extends JFrame 30 { 31 private static final int DEFAULT_WIDTH = 300; 32 private static final int DEFAULT_HEIGHT = 200; 33 34 private File propertiesFile; 35 private Properties settings; 36 37 public PropertiesFrame() 38 { 39 // 从属性获取位置、大小、标题 40 41 String userDir = System.getProperty("user.home"); 42 File propertiesDir = new File(userDir, ".corejava"); 43 if (!propertiesDir.exists()) propertiesDir.mkdir(); 44 propertiesFile = new File(propertiesDir, "program.properties"); 45 46 Properties defaultSettings = new Properties(); 47 defaultSettings.setProperty("left", "0"); 48 defaultSettings.setProperty("top", "0"); 49 defaultSettings.setProperty("width", "" + DEFAULT_WIDTH); 50 defaultSettings.setProperty("height", "" + DEFAULT_HEIGHT); 51 defaultSettings.setProperty("title", ""); 52 53 settings = new Properties(defaultSettings); 54 55 if (propertiesFile.exists()) 56 try (InputStream in = new FileInputStream(propertiesFile)) 57 { 58 settings.load(in); 59 } 60 catch (IOException ex) 61 { 62 ex.printStackTrace(); 63 } 64 65 int left = Integer.parseInt(settings.getProperty("left")); 66 int top = Integer.parseInt(settings.getProperty("top")); 67 int width = Integer.parseInt(settings.getProperty("width")); 68 int height = Integer.parseInt(settings.getProperty("height")); 69 setBounds(left, top, width, height); 70 71 // 如果没有标题,请询问用户 72 73 String title = settings.getProperty("title"); 74 if (title.equals("")) 75 title = JOptionPane.showInputDialog("Please supply a frame title:"); 76 if (title == null) title = ""; 77 setTitle(title); 78 79 addWindowListener(new WindowAdapter() 80 { 81 public void windowClosing(WindowEvent event) 82 { 83 settings.setProperty("left", "" + getX()); 84 settings.setProperty("top", "" + getY()); 85 settings.setProperty("width", "" + getWidth()); 86 settings.setProperty("height", "" + getHeight()); 87 settings.setProperty("title", getTitle()); 88 try (OutputStream out = new FileOutputStream(propertiesFile)) 89 { 90 settings.store(out, "Program Properties"); 91 } 92 catch (IOException ex) 93 { 94 ex.printStackTrace(); 95 } 96 System.exit(0); 97 } 98 }); 99 } 100 }
测试程序3
l 在elipse IDE中调试运行教材593页-594程序13-3,结合程序运行结果理解程序;
l 了解Preferences类中常用的方法;
package preferences;
import java.awt.*;
import java.io.*;
import java.util.prefs.*;
import javax.swing.*;
import javax.swing.filechooser.*;
/**
* 一个测试偏好设置的程序。程序记住框架。位置、大小和标题。
* @version 1.03 2015-06-12
* @author Cay Horstmann
*/
public class PreferencesTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
PreferencesFrame frame = new PreferencesFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}
/**
* 从用户偏好恢复位置和大小并在退出时更新首选项的框架。
*/
class PreferencesFrame extends JFrame
{
private static final int DEFAULT_WIDTH = 300;
private static final int DEFAULT_HEIGHT = 200;
private Preferences root = Preferences.userRoot();
private Preferences node = root.node("/com/horstmann/corejava");
public PreferencesFrame()
{
// 从偏好获得位置、大小、标题
int left = node.getInt("left", 0);
int top = node.getInt("top", 0);
int width = node.getInt("width", DEFAULT_WIDTH);
int height = node.getInt("height", DEFAULT_HEIGHT);
setBounds(left, top, width, height);
// 如果没有标题,请询问用户
String title = node.get("title", "");
if (title.equals(""))
title = JOptionPane.showInputDialog("Please supply a frame title:");
if (title == null) title = "";
setTitle(title);
// 设置显示XML文件的文件选择器
final JFileChooser chooser = new JFileChooser();
chooser.setCurrentDirectory(new File("."));
chooser.setFileFilter(new FileNameExtensionFilter("XML files", "xml"));
// 设置菜单
JMenuBar menuBar = new JMenuBar();
setJMenuBar(menuBar);
JMenu menu = new JMenu("File");
menuBar.add(menu);
JMenuItem exportItem = new JMenuItem("Export preferences");
menu.add(exportItem);
exportItem
.addActionListener(event -> {
if (chooser.showSaveDialog(PreferencesFrame.this) == JFileChooser.APPROVE_OPTION)
{
try
{
savePreferences();
OutputStream out = new FileOutputStream(chooser
.getSelectedFile());
node.exportSubtree(out);
out.close();
}
catch (Exception e)
{
e.printStackTrace();
}
}
});
JMenuItem importItem = new JMenuItem("Import preferences");
menu.add(importItem);
importItem
.addActionListener(event -> {
if (chooser.showOpenDialog(PreferencesFrame.this) == JFileChooser.APPROVE_OPTION)
{
try
{
InputStream in = new FileInputStream(chooser
.getSelectedFile());
Preferences.importPreferences(in);
in.close();
}
catch (Exception e)
{
e.printStackTrace();
}
}
});
JMenuItem exitItem = new JMenuItem("Exit");
menu.add(exitItem);
exitItem.addActionListener(event -> {
savePreferences();
System.exit(0);
});
}
public void savePreferences()
{
node.putInt("left", getX());
node.putInt("top", getY());
node.putInt("width", getWidth());
node.putInt("height", getHeight());
node.put("title", getTitle());
}
}
测试程序4
l 在elipse IDE中调试运行教材619页-622程序13-6,结合程序运行结果理解程序;
l 掌握基于JNLP协议的java Web Start应用程序的发布方法。
package webstart; import java.awt.*; import javax.swing.*; /** * * @version 1.04 2015-06-12 * @author Cay Horstmann */ public class Calculator { public static void main(String[] args) { EventQueue.invokeLater(() -> { CalculatorFrame frame = new CalculatorFrame(); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setVisible(true); }); } }
1 package webstart; 2 3 import java.io.BufferedReader; 4 import java.io.ByteArrayInputStream; 5 import java.io.ByteArrayOutputStream; 6 import java.io.FileNotFoundException; 7 import java.io.IOException; 8 import java.io.InputStream; 9 import java.io.InputStreamReader; 10 import java.io.OutputStream; 11 import java.io.PrintStream; 12 import java.net.MalformedURLException; 13 import java.net.URL; 14 15 import javax.jnlp.BasicService; 16 import javax.jnlp.FileContents; 17 import javax.jnlp.FileOpenService; 18 import javax.jnlp.FileSaveService; 19 import javax.jnlp.PersistenceService; 20 import javax.jnlp.ServiceManager; 21 import javax.jnlp.UnavailableServiceException; 22 import javax.swing.JFrame; 23 import javax.swing.JMenu; 24 import javax.swing.JMenuBar; 25 import javax.swing.JMenuItem; 26 import javax.swing.JOptionPane; 27 28 /** 29 * 一个带有计算器面板和菜单的框架,用来载入和保存计算器历史。 30 */ 31 public class CalculatorFrame extends JFrame 32 { 33 private CalculatorPanel panel; 34 35 public CalculatorFrame() 36 { 37 setTitle(); 38 panel = new CalculatorPanel(); 39 add(panel); 40 41 JMenu fileMenu = new JMenu("File"); 42 JMenuBar menuBar = new JMenuBar(); 43 menuBar.add(fileMenu); 44 setJMenuBar(menuBar); 45 46 JMenuItem openItem = fileMenu.add("Open"); 47 openItem.addActionListener(event -> open()); 48 JMenuItem saveItem = fileMenu.add("Save"); 49 saveItem.addActionListener(event -> save()); 50 51 pack(); 52 } 53 54 55 public void setTitle() 56 { 57 try 58 { 59 String title = null; 60 61 BasicService basic = (BasicService) ServiceManager.lookup("javax.jnlp.BasicService"); 62 URL codeBase = basic.getCodeBase(); 63 64 PersistenceService service = (PersistenceService) ServiceManager 65 .lookup("javax.jnlp.PersistenceService"); 66 URL key = new URL(codeBase, "title"); 67 68 try 69 { 70 FileContents contents = service.get(key); 71 InputStream in = contents.getInputStream(); 72 BufferedReader reader = new BufferedReader(new InputStreamReader(in)); 73 title = reader.readLine(); 74 } 75 catch (FileNotFoundException e) 76 { 77 title = JOptionPane.showInputDialog("Please supply a frame title:"); 78 if (title == null) return; 79 80 service.create(key, 100); 81 FileContents contents = service.get(key); 82 OutputStream out = contents.getOutputStream(true); 83 PrintStream printOut = new PrintStream(out); 84 printOut.print(title); 85 } 86 setTitle(title); 87 } 88 catch (UnavailableServiceException | IOException e) 89 { 90 JOptionPane.showMessageDialog(this, e); 91 } 92 } 93 94 95 96 97 public void open() 98 { 99 try 100 { 101 FileOpenService service = (FileOpenService) ServiceManager 102 .lookup("javax.jnlp.FileOpenService"); 103 FileContents contents = service.openFileDialog(".", new String[] { "txt" }); 104 105 JOptionPane.showMessageDialog(this, contents.getName()); 106 if (contents != null) 107 { 108 InputStream in = contents.getInputStream(); 109 BufferedReader reader = new BufferedReader(new InputStreamReader(in)); 110 String line; 111 while ((line = reader.readLine()) != null) 112 { 113 panel.append(line); 114 panel.append(" "); 115 } 116 } 117 } 118 catch (UnavailableServiceException e) 119 { 120 JOptionPane.showMessageDialog(this, e); 121 } 122 catch (IOException e) 123 { 124 JOptionPane.showMessageDialog(this, e); 125 } 126 } 127 128 129 130 public void save() 131 { 132 try 133 { 134 ByteArrayOutputStream out = new ByteArrayOutputStream(); 135 PrintStream printOut = new PrintStream(out); 136 printOut.print(panel.getText()); 137 InputStream data = new ByteArrayInputStream(out.toByteArray()); 138 FileSaveService service = (FileSaveService) ServiceManager 139 .lookup("javax.jnlp.FileSaveService"); 140 service.saveFileDialog(".", new String[] { "txt" }, data, "calc.txt"); 141 } 142 catch (UnavailableServiceException e) 143 { 144 JOptionPane.showMessageDialog(this, e); 145 } 146 catch (IOException e) 147 { 148 JOptionPane.showMessageDialog(this, e); 149 } 150 } 151 }
1 package webstart; 2 3 import java.awt.*; 4 import java.awt.event.*; 5 import javax.swing.*; 6 import javax.swing.text.*; 7 8 public class CalculatorPanel extends JPanel 9 { 10 private JTextArea display; 11 private JPanel panel; 12 private double result; 13 private String lastCommand; 14 private boolean start; 15 16 17 18 public CalculatorPanel() 19 { 20 setLayout(new BorderLayout()); 21 22 result = 0; 23 lastCommand = "="; 24 start = true; 25 26 // 添加显示 27 display = new JTextArea(10, 20); 28 29 add(new JScrollPane(display), BorderLayout.NORTH); 30 31 ActionListener insert = new InsertAction(); 32 ActionListener command = new CommandAction(); 33 34 // 在4×4网格中添加按钮 35 36 panel = new JPanel(); 37 panel.setLayout(new GridLayout(4, 4)); 38 39 addButton("7", insert); 40 addButton("8", insert); 41 addButton("9", insert); 42 addButton("/", command); 43 44 addButton("4", insert); 45 addButton("5", insert); 46 addButton("6", insert); 47 addButton("*", command); 48 49 addButton("1", insert); 50 addButton("2", insert); 51 addButton("3", insert); 52 addButton("-", command); 53 54 addButton("0", insert); 55 addButton(".", insert); 56 addButton("=", command); 57 addButton("+", command); 58 59 add(panel, BorderLayout.CENTER); 60 } 61 62 63 public String getText() 64 { 65 return display.getText(); 66 } 67 68 69 public void append(String s) 70 { 71 display.append(s); 72 } 73 74 75 private void addButton(String label, ActionListener listener) 76 { 77 JButton button = new JButton(label); 78 button.addActionListener(listener); 79 panel.add(button); 80 } 81 82 private class InsertAction implements ActionListener 83 { 84 public void actionPerformed(ActionEvent event) 85 { 86 String input = event.getActionCommand(); 87 start = false; 88 display.append(input); 89 } 90 } 91 92 93 private class CommandAction implements ActionListener 94 { 95 public void actionPerformed(ActionEvent event) 96 { 97 String command = event.getActionCommand(); 98 99 if (start) 100 { 101 if (command.equals("-")) 102 { 103 display.append(command); 104 start = false; 105 } 106 else 107 lastCommand = command; 108 } 109 else 110 { 111 try 112 { 113 int lines = display.getLineCount(); 114 int lineStart = display.getLineStartOffset(lines - 1); 115 int lineEnd = display.getLineEndOffset(lines - 1); 116 String value = display.getText(lineStart, lineEnd - lineStart); 117 display.append(" "); 118 display.append(command); 119 calculate(Double.parseDouble(value)); 120 if (command.equals("=")) 121 display.append(" " + result); 122 lastCommand = command; 123 display.append(" "); 124 start = true; 125 } 126 catch (BadLocationException e) 127 { 128 e.printStackTrace(); 129 } 130 } 131 } 132 } 133 134 135 public void calculate(double x) 136 { 137 if (lastCommand.equals("+")) result += x; 138 else if (lastCommand.equals("-")) result -= x; 139 else if (lastCommand.equals("*")) result *= x; 140 else if (lastCommand.equals("/")) result /= x; 141 else if (lastCommand.equals("=")) result = x; 142 } 143 }
没有调试成功
实验2:GUI综合编程练习
按实验十四分组名单,组内讨论完成以下编程任务:
练习1:采用GUI界面设计以下程序,并进行部署与发布:
编制一个程序,将身份证号.txt 中的信息读入到内存中;
按姓名字典序
输出人员信息;
查询最大年龄的人员信息;
查询最小年龄人员信息;
输入你的年龄,查询身份证号.txt中年龄与你最近人的姓名、身份证号、年龄、性别和出生地;
查询人员中是否有你的同乡。
输入身份证信息,查询所提供身份证号的人员信息,要求输入一个身份证数字时,查询界面就显示满足查询条件的查询结果,且随着输入的数字的增多,查询匹配的范围逐渐缩小。
1 package AA; 2 3 import java.awt.*; 4 import javax.swing.*; 5 6 public class IdTest { 7 public static void main(String[] args) { 8 EventQueue.invokeLater(() -> { 9 JFrame frame = new Main(); 10 frame.setTitle("身份证信息查询"); 11 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 12 frame.setVisible(true); 13 }); 14 } 15 }
package AA; import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.InputStreamReader; import java.io.FileNotFoundException; import java.io.IOException; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.Scanner; import java.awt.*; import javax.swing.*; import java.awt.event.*; public class Main extends JFrame { private static ArrayList<Student> studentlist; private static ArrayList<Student> list; private JPanel panel; private JPanel buttonPanel; private static final int DEFAULT_WITH = 900; private static final int DEFAULT_HEIGHT = 600; public Main() { studentlist = new ArrayList<>(); Scanner scanner = new Scanner(System.in); File file = new File("G:\身份证号.txt"); try { FileInputStream fis = new FileInputStream(file); BufferedReader in = new BufferedReader(new InputStreamReader(fis)); String temp = null; while ((temp = in.readLine()) != null) { Scanner linescanner = new Scanner(temp); linescanner.useDelimiter(" "); String name = linescanner.next(); String number = linescanner.next(); String sex = linescanner.next(); String age = linescanner.next(); String province = linescanner.nextLine(); Student student = new Student(); student.setName(name); student.setnumber(number); student.setsex(sex); int a = Integer.parseInt(age); student.setage(a); student.setprovince(province); studentlist.add(student); } } catch (FileNotFoundException e) { System.out.println("文件找不到"); e.printStackTrace(); } catch (IOException e) { System.out.println("文件读取错误"); e.printStackTrace(); } panel = new JPanel(); panel.setLayout(new BorderLayout()); JTextArea A = new JTextArea(); panel.add(A); add(panel, BorderLayout.NORTH); buttonPanel = new JPanel(); buttonPanel.setLayout(new GridLayout(6, 2)); JButton jButton = new JButton("字典排序"); JButton jButton1 = new JButton("年龄最大和年龄最小"); JLabel lab1 = new JLabel("寻找你的老乡"); JTextField a1 = new JTextField(); JLabel lab2 = new JLabel("寻找找同龄人:"); JTextField a2 = new JTextField(); JLabel lab3 = new JLabel("输入身份证号码查询信息:"); JTextField a3 = new JTextField(); JButton jButton2 = new JButton("退出"); jButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { Collections.sort(studentlist); A.setText(studentlist.toString()); } }); jButton1.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { int max = 0, min = 100; int j, k1 = 0, k2 = 0; for (int i = 1; i < studentlist.size(); i++) { j = studentlist.get(i).getage(); if (j > max) { max = j; k1 = i; } if (j < min) { min = j; k2 = i; } } A.setText("年龄最大:" + studentlist.get(k1) + "年龄最小:" + studentlist.get(k2)); } }); jButton2.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { dispose(); System.exit(0); } }); a1.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { String find = a1.getText(); String text=""; String place = find.substring(0, 3); for (int i = 0; i < studentlist.size(); i++) { if (studentlist.get(i).getprovince().substring(1, 4).equals(place)) { text+=" "+studentlist.get(i); A.setText("老乡:" + text); } } } }); a2.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { String yourage = a2.getText(); int a = Integer.parseInt(yourage); int near = agenear(a); int value = a - studentlist.get(near).getage(); A.setText("年龄相近:" + studentlist.get(near)); } }); a3.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { list = new ArrayList<>(); Collections.sort(studentlist); String key = a3.getText(); for (int i = 1; i < studentlist.size(); i++) { if (studentlist.get(i).getnumber().contains(key)) { list.add(studentlist.get(i)); A.setText("结果: " + list); } } } }); buttonPanel.add(jButton); buttonPanel.add(jButton1); buttonPanel.add(lab1); buttonPanel.add(a1); buttonPanel.add(lab2); buttonPanel.add(a2); buttonPanel.add(lab3); buttonPanel.add(a3); buttonPanel.add(jButton2); add(buttonPanel, BorderLayout.SOUTH); setSize(DEFAULT_WITH, DEFAULT_HEIGHT); } public static int agenear(int age) { int min = 53, value = 0, k = 0; for (int i = 0; i < studentlist.size(); i++) { value = studentlist.get(i).getage() - age; if (value < 0) value = -value; if (value < min) { min = value; k = i; } } return k; } }
package AA; public class Student implements Comparable<Student> { private String name; private String number ; private String sex ; private int age; private String province; public String getName() { return name; } public void setName(String name) { this.name = name; } public String getnumber() { return number; } public void setnumber(String number) { this.number = number; } public String getsex() { return sex ; } public void setsex(String sex ) { this.sex =sex ; } public int getage() { return age; } public void setage(int age) { this.age= age; } public String getprovince() { return province; } public void setprovince(String province) { this.province=province ; } public int compareTo(Student o) { return this.name.compareTo(o.getName()); } public String toString() { return name+" "+sex+" "+age+" "+number+" "+province+" "; } }
练习2:采用GUI界面设计以下程序,并进行部署与发布
编写一个计算器类,可以完成加、减、乘、除的操作
利用计算机类,设计一个小学生100以内数的四则运算练习程序,由计算机随机产生10道加减乘除练习题,学生输入答案,由程序检查答案是否正确,每道题正确计10分,错误不计分,10道题测试结束后给出测试总分;
将程序中测试练习题及学生答题结果输出到文件,文件名为test.txt。
1 package BB; 2 3 4 import java.awt.Dimension; 5 import java.awt.EventQueue; 6 import java.awt.Toolkit; 7 8 import javax.swing.JFrame; 9 10 public class Main{ 11 12 public static void main (String args[]) 13 { 14 Toolkit t=Toolkit.getDefaultToolkit(); 15 Dimension s=t.getScreenSize(); 16 EventQueue.invokeLater(() -> { 17 JFrame frame = new Calcultor(); 18 frame.setBounds(0, 0,(int)s.getWidth()/2,(int)s.getHeight()/2); 19 frame.setTitle("练习界面"); 20 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 21 frame.setVisible(true); 22 }); 23 } 24 25 }
1 package BB; 2 3 4 import java.awt.BorderLayout; 5 import java.awt.Font; 6 import java.awt.GridLayout; 7 import java.awt.event.ActionEvent; 8 import java.awt.event.ActionListener; 9 import java.io.FileNotFoundException; 10 import java.io.PrintWriter; 11 import java.util.Collections; 12 import java.util.Scanner; 13 14 import javax.swing.*; 15 16 import java.math.*; 17 18 19 public class Calcultor extends JFrame { 20 21 private static final int DEFAULT_WITH = 900; 22 private static final int DEFAULT_HEIGHT = 600; 23 private String[] c=new String[10]; 24 private String[] c1=new String[10]; 25 private int[] list=new int[10]; 26 int i=0,i1=0,sum = 0; 27 private PrintWriter out = null; 28 private JTextArea text,text1; 29 private int counter; 30 private JPanel buttonPanel; 31 32 public Calcultor() { 33 JPanel Panel = new JPanel(); 34 35 Panel.setLayout(null); 36 JLabel JLabel1=new JLabel("题目"); 37 38 buttonPanel = new JPanel(); 39 buttonPanel.setLayout(new GridLayout(1, 3)); 40 41 JButton Button = new JButton("生成题目"); 42 43 JButton Button2 = new JButton("确认答案"); 44 45 JButton Button3 = new JButton("读出文本"); 46 47 48 Button.addActionListener(new Action()); 49 Button2.addActionListener(new Action1()); 50 Button3.addActionListener(new Action2()); 51 52 text=new JTextArea(30,80); 53 text.setBounds(50, 50, 200, 50); 54 //text.setFont(new Font("Courier",Font.PLAIN,35)); 55 56 text1=new JTextArea(30,80); 57 text1.setBounds(270, 50, 200, 50); 58 //text1.setFont(new Font("Courier",Font.PLAIN,35)); 59 60 Panel.add(text); 61 Panel.add(text1); 62 63 buttonPanel.add(Button); 64 buttonPanel.add(Button2); 65 buttonPanel.add(Button3); 66 Panel.add(JLabel1); 67 add(Panel,BorderLayout.NORTH); 68 add(buttonPanel, BorderLayout.SOUTH); 69 70 71 72 } 73 74 private class Action implements ActionListener 75 { 76 public void actionPerformed(ActionEvent event) 77 { 78 text1.setText("0"); 79 if(i<10) { 80 81 int a = 1+(int)(Math.random() * 99); 82 int b = 1+(int)(Math.random() * 99); 83 int m= (int) Math.round(Math.random() * 3); 84 switch(m) 85 { 86 case 0: 87 while(a<b){ 88 b = (int) Math.round(Math.random() * 100); 89 a = (int) Math.round(Math.random() * 100); 90 } 91 c[i]=(i+":"+a+"/"+b+"="); 92 list[i]=Math.floorDiv(a, b); 93 text.setText(i+":"+a+"/"+b+"="); 94 i++; 95 break; 96 case 1: 97 c[i]=(i+":"+a+"*"+b+"="); 98 list[i]=Math.multiplyExact(a, b); 99 text.setText(i+":"+a+"*"+b+"="); 100 i++; 101 break; 102 case 2: 103 c[i]=(i+":"+a+"+"+b+"="); 104 list[i]=Math.addExact(a, b); 105 text.setText(i+":"+a+"+"+b+"="); 106 i++; 107 break ; 108 case 3: 109 while(a<=b){ 110 b = (int) Math.round(Math.random() * 100); 111 a = (int) Math.round(Math.random() * 100); 112 } 113 c[i]=(i+":"+a+"-"+b+"="); 114 text.setText(i+":"+a+"-"+b+"="); 115 list[i]=Math.subtractExact(a, b); 116 i++; 117 break ; 118 } 119 } 120 } 121 } 122 private class Action1 implements ActionListener 123 { 124 public void actionPerformed(ActionEvent event) 125 { 126 if(i<10) { 127 text.setText(null); 128 String daan=text1.getText().toString().trim(); 129 int a = Integer.parseInt(daan); 130 if(text1.getText()!="") { 131 if(list[i1]==a) sum+=10; 132 } 133 c1[i1]=daan; 134 i1++; 135 } 136 } 137 } 138 139 140 private class Action2 implements ActionListener 141 { 142 public void actionPerformed(ActionEvent event) 143 { 144 145 try { 146 out = new PrintWriter("text.txt"); 147 } catch (FileNotFoundException e) { 148 // TODO Auto-generated catch block 149 e.printStackTrace(); 150 } 151 for(int counter=0;counter<10;counter++) 152 { 153 out.println(c[counter]+c1[counter]); 154 } 155 out.println("成绩"+sum); 156 out.close(); 157 158 } 159 160 } 161
第三部分:
本周的作业没有完成。我意识到学习陷入了一种问题堆积的恶性循环,目前处于很危险的学习状态。