王颖奇 20171010129《面向对象程序设计（java）》第十五周学习总结

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王颖奇 20171010129《面向对象程序设计（java）》第十五周学习总结

阅读原文时间：2023年07月10日阅读：1

实验十五 GUI编程练习与应用程序部署

实验时间 2018-12-6

学习总结：

理论部分：

◼ 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。

jar命令
1 jar命令格式：
jar {ctxui} [vfm0Me] [jar-file] [manifest-file] [entry-point] [-C dir] files …
2 Jar命令选项（教材581页表13-1）：
– -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

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。

更换位置后仍可运行

l 掌握创建JAR文件的方法；

代码：

package resource;

import java.awt.*;
import java.io.*;
import java.net.*;
import java.util.*;
import javax.swing.*;

/**
* @version 1.41 2015-06-12
* @author Cay Horstmann
*/
public class ResourceTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
JFrame frame = new ResourceTestFrame();
frame.setTitle("ResourceTest");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

/**
* A frame that loads image and text resources.
*/
class ResourceTestFrame extends JFrame
{
private static final int DEFAULT_WIDTH = 300;
private static final int DEFAULT_HEIGHT = 300;

public ResourceTestFrame()
{
setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
//返回类，并查找带有给定名称的资源。
URL aboutURL = getClass().getResource("about.gif");
Image img = new ImageIcon(aboutURL).getImage();
setIconImage(img);
//读取文件夹内容，写入到文本区中
JTextArea textArea = new JTextArea();
InputStream stream = getClass().getResourceAsStream("about.txt");
try (Scanner in = new Scanner(stream, "UTF-8"))
{
while (in.hasNext())
textArea.append(in.nextLine() + "\n");
}
add(textArea);
}
}

ResourceTest

运行结果：

测试程序2

l 在elipse IDE中调试运行教材588页-589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；

代码：

package properties;

import java.awt.EventQueue;
import java.awt.event.*;
import java.io.*;
import java.util.Properties;

import javax.swing.*;

/**
* A program to test properties. The program remembers the frame position, size,
* and title.
* @version 1.01 2015-06-16
* @author Cay Horstmann
*/
public class PropertiesTest
{
public static void main(String[] args)
{
EventQueue.invokeLater(() -> {
PropertiesFrame frame = new PropertiesFrame();
frame.setVisible(true);
});
}
}

/**
* A frame that restores position and size from a properties file and updates
* the properties upon exit.
*/
class PropertiesFrame extends JFrame
{
private static final int DEFAULT_WIDTH = 300;
private static final int DEFAULT_HEIGHT = 200;

private File propertiesFile;
private Properties settings;

public PropertiesFrame()
{
// 从属性中获取位置、大小和标题

  String userDir = System.getProperty("user.home");  
  File propertiesDir = new File(userDir, ".corejava");  
  if (!propertiesDir.exists()) propertiesDir.mkdir();  
  propertiesFile = new File(propertiesDir, "program.properties");

  Properties defaultSettings = new Properties();  
  defaultSettings.setProperty("left", "0");  
  defaultSettings.setProperty("top", "0");  
  defaultSettings.setProperty("width", "" + DEFAULT\_WIDTH);  
  defaultSettings.setProperty("height", "" + DEFAULT\_HEIGHT);  
  defaultSettings.setProperty("title", "");

  settings = new Properties(defaultSettings);

  if (propertiesFile.exists())  
     try (InputStream in = new FileInputStream(propertiesFile))  
     {  
        settings.load(in);  
     }  
     catch (IOException ex)  
     {  
        ex.printStackTrace();  
     }

  int left = Integer.parseInt(settings.getProperty("left"));  
  int top = Integer.parseInt(settings.getProperty("top"));  
  int width = Integer.parseInt(settings.getProperty("width"));  
  int height = Integer.parseInt(settings.getProperty("height"));  
  setBounds(left, top, width, height);

  // 如果没有标题，询问用户

  String title = settings.getProperty("title");  
  if (title.equals(""))  
     title = JOptionPane.showInputDialog("Please supply a frame title:");  
  if (title == null) title = "";  
  setTitle(title);  
  //添加指定的窗口侦听器，以从此窗口接收窗口事件。  
  addWindowListener(new WindowAdapter()  
  {  
     public void windowClosing(WindowEvent event)  
     {  
        settings.setProperty("left", "" + getX());  
        settings.setProperty("top", "" + getY());  
        settings.setProperty("width", "" + getWidth());  
        settings.setProperty("height", "" + getHeight());  
        settings.setProperty("title", getTitle());  
        try (OutputStream out = new FileOutputStream(propertiesFile))  
        {  
           settings.store(out, "Program Properties");  
        }  
        catch (IOException ex)  
        {  
           ex.printStackTrace();  
        }  
        System.exit(0);  
     }  
  });

}
}

PropertiesTest

运行结果：

添加title的名字wyq

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；

代码：

package preferences;

import java.awt.*;
import java.io.*;
import java.util.prefs.*;

import javax.swing.*;
import javax.swing.filechooser.*;

/**
* A program to test preference settings. The program remembers the frame
* position, size, and title.
* @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);
});
}
}

/**
* A frame that restores position and size from user preferences and updates the
* preferences upon exit.
*/
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()
{
// get position, size, title from preferences

  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);

  // if no title given, ask user

  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());
}
}

PreferencesTest

运行结果：

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。

代码：

package webstart;

import java.awt.*;
import javax.swing.*;

/**
* A calculator with a calculation history that can be deployed as a Java Web Start application.
* @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);
});
}
}

Calculator

package webstart;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintStream;
import java.net.MalformedURLException;
import java.net.URL;

import javax.jnlp.BasicService;
import javax.jnlp.FileContents;
import javax.jnlp.FileOpenService;
import javax.jnlp.FileSaveService;
import javax.jnlp.PersistenceService;
import javax.jnlp.ServiceManager;
import javax.jnlp.UnavailableServiceException;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;

/**
* A frame with a calculator panel and a menu to load and save the calculator history.
*/
public class CalculatorFrame extends JFrame
{
private CalculatorPanel panel;

public CalculatorFrame()
{
setTitle();
panel = new CalculatorPanel();
add(panel);

  JMenu fileMenu = new JMenu("File");  
  JMenuBar menuBar = new JMenuBar();  
  menuBar.add(fileMenu);  
  setJMenuBar(menuBar);

  JMenuItem openItem = fileMenu.add("Open");  
  openItem.addActionListener(event -> open());  
  JMenuItem saveItem = fileMenu.add("Save");  
  saveItem.addActionListener(event -> save());

  pack();

}

/**
* Gets the title from the persistent store or asks the user for the title if there is no prior
* entry.
*/
public void setTitle()
{
try
{
String title = null;

     BasicService basic = (BasicService) ServiceManager.lookup("javax.jnlp.BasicService");  
     URL codeBase = basic.getCodeBase();

     PersistenceService service = (PersistenceService) ServiceManager  
           .lookup("javax.jnlp.PersistenceService");  
     URL key = new URL(codeBase, "title");

     try  
     {  
        FileContents contents = service.get(key);  
        InputStream in = contents.getInputStream();  
        BufferedReader reader = new BufferedReader(new InputStreamReader(in));  
        title = reader.readLine();  
     }  
     catch (FileNotFoundException e)  
     {  
        title = JOptionPane.showInputDialog("Please supply a frame title:");  
        if (title == null) return;

        service.create(key, 100);  
        FileContents contents = service.get(key);  
        OutputStream out = contents.getOutputStream(true);  
        PrintStream printOut = new PrintStream(out);  
        printOut.print(title);  
     }  
     setTitle(title);  
  }  
  catch (UnavailableServiceException | IOException e)  
  {  
     JOptionPane.showMessageDialog(this, e);  
  }

}

/**
* Opens a history file and updates the display.
*/
public void open()
{
try
{
FileOpenService service = (FileOpenService) ServiceManager
.lookup("javax.jnlp.FileOpenService");
FileContents contents = service.openFileDialog(".", new String[] { "txt" });

     JOptionPane.showMessageDialog(this, contents.getName());  
     if (contents != null)  
     {  
        InputStream in = contents.getInputStream();  
        BufferedReader reader = new BufferedReader(new InputStreamReader(in));  
        String line;  
        while ((line = reader.readLine()) != null)  
        {  
           panel.append(line);  
           panel.append("\\n");  
        }  
     }  
  }  
  catch (UnavailableServiceException e)  
  {  
     JOptionPane.showMessageDialog(this, e);  
  }  
  catch (IOException e)  
  {  
     JOptionPane.showMessageDialog(this, e);  
  }

}

/**
* Saves the calculator history to a file.
*/
public void save()
{
try
{
ByteArrayOutputStream out = new ByteArrayOutputStream();
PrintStream printOut = new PrintStream(out);
printOut.print(panel.getText());
InputStream data = new ByteArrayInputStream(out.toByteArray());
FileSaveService service = (FileSaveService) ServiceManager
.lookup("javax.jnlp.FileSaveService");
service.saveFileDialog(".", new String[] { "txt" }, data, "calc.txt");
}
catch (UnavailableServiceException e)
{
JOptionPane.showMessageDialog(this, e);
}
catch (IOException e)
{
JOptionPane.showMessageDialog(this, e);
}
}
}

CalculatorFrame

package webstart;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.text.*;

/**
A panel with calculator buttons and a result display.
*/
public class CalculatorPanel extends JPanel
{
private JTextArea display;
private JPanel panel;
private double result;
private String lastCommand;
private boolean start;

/**
Lays out the panel.
*/
public CalculatorPanel()
{
setLayout(new BorderLayout());

  result = 0;  
  lastCommand = "=";  
  start = true;

  // add the display

  display = new JTextArea(10, 20);

  add(new JScrollPane(display), BorderLayout.NORTH);

  ActionListener insert = new InsertAction();  
  ActionListener command = new CommandAction();

  // add the buttons in a 4 x 4 grid

  panel = new JPanel();  
  panel.setLayout(new GridLayout(4, 4));

  addButton("7", insert);  
  addButton("8", insert);  
  addButton("9", insert);  
  addButton("/", command);

  addButton("4", insert);  
  addButton("5", insert);  
  addButton("6", insert);  
  addButton("\*", command);

  addButton("1", insert);  
  addButton("2", insert);  
  addButton("3", insert);  
  addButton("-", command);

  addButton("0", insert);  
  addButton(".", insert);  
  addButton("=", command);  
  addButton("+", command);

  add(panel, BorderLayout.CENTER);

}

/**
Gets the history text.
@return the calculator history
*/
public String getText()
{
return display.getText();
}

/**
Appends a string to the history text.
@param s the string to append
*/
public void append(String s)
{
display.append(s);
}

/**
Adds a button to the center panel.
@param label the button label
@param listener the button listener
*/
private void addButton(String label, ActionListener listener)
{
JButton button = new JButton(label);
button.addActionListener(listener);
panel.add(button);
}

/**
This action inserts the button action string to the
end of the display text.
*/
private class InsertAction implements ActionListener
{
public void actionPerformed(ActionEvent event)
{
String input = event.getActionCommand();
start = false;
display.append(input);
}
}

/**
This action executes the command that the button
action string denotes.
*/
private class CommandAction implements ActionListener
{
public void actionPerformed(ActionEvent event)
{
String command = event.getActionCommand();

     if (start)  
     {  
        if (command.equals("-"))  
        {  
           display.append(command);  
           start = false;  
        }  
        else  
           lastCommand = command;  
     }  
     else  
     {  
        try  
        {  
           int lines = display.getLineCount();  
           int lineStart = display.getLineStartOffset(lines - 1);  
           int lineEnd = display.getLineEndOffset(lines - 1);  
           String value = display.getText(lineStart, lineEnd - lineStart);  
           display.append(" ");  
           display.append(command);  
           calculate(Double.parseDouble(value));  
           if (command.equals("="))  
              display.append("\\n" + result);  
           lastCommand = command;  
           display.append("\\n");  
           start = true;  
        }  
        catch (BadLocationException e)  
        {  
           e.printStackTrace();  
        }  
     }  
  }

}

/**
Carries out the pending calculation.
@param x the value to be accumulated with the prior result.
*/
public void calculate(double x)
{
if (lastCommand.equals("+")) result += x;
else if (lastCommand.equals("-")) result -= x;
else if (lastCommand.equals("*")) result *= x;
else if (lastCommand.equals("/")) result /= x;
else if (lastCommand.equals("=")) result = x;
}
}

CalculatorPanel

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：

l 编制一个程序，将身份证号.txt 中的信息读入到内存中；

l 按姓名字典序输出人员信息；

l 查询最大年龄的人员信息；

l 查询最小年龄人员信息；

l 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；

l 查询人员中是否有你的同乡。

l 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。

代码：

改进前：

package demo1;

import java.awt.*;
import javax.swing.*;

public class ButtonTest {
public static void main(String[] args) {
EventQueue.invokeLater(() -> {
JFrame frame = new Main();
frame.setTitle("身份证");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
});
}
}

ButtonTest

package demo1;

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 studentlist;
private static ArrayList list;
private JPanel panel;
private JPanel buttonPanel;
private static final int DEFAULT_WITH = 600;
private static final int DEFAULT_HEIGHT = 300;

public Main() {  
    studentlist = new ArrayList<>();  
    Scanner scanner = new Scanner(System.in);  
    File file = new File("C:\\\\Users\\\\ASUS\\\\Desktop\\\\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("学生信息文件找不到");  
        e.printStackTrace();  
    } catch (IOException e) {  
        System.out.println("学生信息文件读取错误");  
        e.printStackTrace();  
    }  
    panel = new JPanel();  
    panel.setLayout(new BorderLayout());  
    JTextArea jt = new JTextArea();  
    panel.add(jt);  
    add(panel, BorderLayout.NORTH);  
    buttonPanel = new JPanel();  
    buttonPanel.setLayout(new GridLayout(1, 7));  
    JButton jButton = new JButton("字典排序");  
    JButton jButton1 = new JButton("年龄最大和年龄最小");  
    JLabel lab = new JLabel("猜猜你的老乡");  
    JTextField jt1 = new JTextField();  
    JLabel lab1 = new JLabel("找找同龄人（年龄相近）：");  
    JTextField jt2 = new JTextField();  
    JLabel lab2 = new JLabel("输入你的身份证号码：");  
    JTextField jt3 = new JTextField();  
    JButton jButton2 = new JButton("退出");  
    jButton.setBounds(110, 90, 60, 30);  
    jButton1.setBounds(110, 90, 60, 30);  
    jt1.setBounds(110, 90, 60, 30);  
    jt2.setBounds(110, 90, 60, 30);  
    jt3.setBounds(110, 90, 60, 30);  
    jButton2.setBounds(110, 90, 60, 30);  
    jButton.addActionListener(new ActionListener() {  
        public void actionPerformed(ActionEvent e) {  
            Collections.sort(studentlist);  
            jt.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;  
                }

            }  
            jt.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);  
        }  
    });  
    jt1.addActionListener(new ActionListener() {  
        public void actionPerformed(ActionEvent e) {  
            String find = jt1.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+="\\n"+studentlist.get(i);  
                    jt.setText("老乡：" + text);  
                }  
            }  
        }  
    });  
    jt2.addActionListener(new ActionListener() {  
        public void actionPerformed(ActionEvent e) {  
            String yourage = jt2.getText();  
            int a = Integer.parseInt(yourage);  
            int near = agenear(a);  
            int value = a - studentlist.get(near).getage();  
            jt.setText("年龄相近：" + studentlist.get(near));  
        }  
    });  
    jt3.addActionListener(new ActionListener() {  
        public void actionPerformed(ActionEvent e) {  
            list = new ArrayList<>();  
            Collections.sort(studentlist);  
            String key = jt3.getText();  
            for (int i = 1; i < studentlist.size(); i++) {  
                if (studentlist.get(i).getnumber().contains(key)) {  
                    list.add(studentlist.get(i));  
                    jt.setText("emmm！你可能是：\\n" + list);  
                    //System.out.println("可能的人：" + studentlist.get(i));  
                    //jt.setText("可能的人：" + studentlist.get(i));  
                }  
            }  
        }  
    });  
    buttonPanel.add(jButton);  
    buttonPanel.add(jButton1);  
    buttonPanel.add(lab);  
    buttonPanel.add(jt1);  
    buttonPanel.add(lab1);  
    buttonPanel.add(jt2);  
    buttonPanel.add(lab2);  
    buttonPanel.add(jt3);  
    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;  
}

}

Main

Student：

package demo1;

public class Student implements Comparable {

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) {  
        // int a = Integer.parseInt(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+"\\t"+sex+"\\t"+age+"\\t"+number+"\\t"+province+"\\n";  
}

}

Student

改进后的Main（请使用该段代码，才能完成实验要求）：

package demo1;

public Main() {  
    studentlist = new ArrayList<>();  
    Scanner scanner = new Scanner(System.in);  
    File file = new File("C:\\\\Users\\\\ASUS\\\\Desktop\\\\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("学生信息文件找不到");  
        e.printStackTrace();  
    } catch (IOException e) {  
        System.out.println("学生信息文件读取错误");  
        e.printStackTrace();  
    }  
    panel = new JPanel();  
    panel.setLayout(new BorderLayout());  
    JTextArea jt = new JTextArea();  
    panel.add(jt);  
    add(panel, BorderLayout.NORTH);  
    buttonPanel = new JPanel();  
    buttonPanel.setLayout(new GridLayout(1, 7));  
    JButton jButton = new JButton("字典排序");  
    JButton jButton1 = new JButton("年龄最大和年龄最小");  
    JLabel lab = new JLabel("猜猜你的老乡");  
    JTextField jt1 = new JTextField();  
    JLabel lab1 = new JLabel("找找同龄人（年龄相近）：");  
    JTextField jt2 = new JTextField();  
    JLabel lab2 = new JLabel("输入你的身份证号码：");  
    JTextField jt3 = new JTextField();  
    JButton jButton2 = new JButton("退出");  
    jButton.setBounds(110, 90, 60, 30);  
    jButton1.setBounds(110, 90, 60, 30);  
    jt1.setBounds(110, 90, 60, 30);  
    jt2.setBounds(110, 90, 60, 30);  
    jt3.setBounds(110, 90, 60, 30);  
    jButton2.setBounds(110, 90, 60, 30);  
    jButton.addActionListener(new ActionListener() {  
        public void actionPerformed(ActionEvent e) {  
            Collections.sort(studentlist);  
            jt.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;  
                }

            }  
            jt.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);  
        }  
    });  
    jt1.addActionListener(new ActionListener() {  
        public void actionPerformed(ActionEvent e) {  
            String find = jt1.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 += "\\n" + studentlist.get(i);  
                    jt.setText("老乡：" + text);  
                }  
            }  
        }  
    });  
    jt2.addActionListener(new ActionListener() {  
        public void actionPerformed(ActionEvent e) {  
            String yourage = jt2.getText();  
            int a = Integer.parseInt(yourage);  
            int near = agenear(a);  
            int value = a - studentlist.get(near).getage();  
            jt.setText("年龄相近：" + studentlist.get(near));  
        }  
    });

    jt3.addKeyListener(new KeyAdapter() {  
        public void keyTyped(KeyEvent e) {  
            list = new ArrayList<>();  
            Collections.sort(studentlist);  
            String key = jt3.getText();

            for (int i = 1; i < studentlist.size(); i++) {  
                if (studentlist.get(i).getnumber().contains(key)) {  
                    list.add(studentlist.get(i));  
                    jt.setText("emmm！你可能是：\\n" + list);  
                }  
            }  
        }

    });  
    buttonPanel.add(jButton);  
    buttonPanel.add(jButton1);  
    buttonPanel.add(lab);  
    buttonPanel.add(jt1);  
    buttonPanel.add(lab1);  
    buttonPanel.add(jt2);  
    buttonPanel.add(lab2);  
    buttonPanel.add(jt3);  
    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;  
}

}

Main

由于使用了addActionListener来添加事件监听器，改进前的程序只能通过敲击回车，才能触发事件的发生（模糊查找的部分）

通过改进，使用addKeyListener来添加事件监听器，不需要使用计时器的方法，也能实现要求（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）

运行结果：

字典排序：

1.查询最大年龄的人员信息；

2.查询最小年龄人员信息；

找老乡：

年龄相近的人：

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。

输入数字2时：

输入数字26时：

输入数字265时：

练习2：采用GUI界面设计以下程序，并进行部署与发布

l 编写一个计算器类，可以完成加、减、乘、除的操作

l 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；

l 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。

代码：

package ui_test;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;

import javax.swing.*;

public class MyExGUI extends JFrame {
ArrayList user_zongti = new ArrayList();
ArrayList user_zonganswer = new ArrayList();
ArrayList user_answer = new ArrayList();
ArrayList true_answer = new ArrayList();
ArrayList jta_timu = new ArrayList();
ArrayList jta_zong = new ArrayList();
ArrayList user_fenshu = new ArrayList();
JMenuBar jm; // 菜单条组件
JMenu menu;// 菜单
JMenuItem item1, item2;// 菜单项
JMenu build; // 二级菜单
JMenuItem file, project;
TextArea answer_all = new TextArea();
TextField jta = new TextField();
TextField jta_answer = new TextField();
JLabel num_answer = new JLabel();
JLabel answer;
JToolBar jtb;// 工具条
JButton jb1, jb2, jb3, jb4, jb5, jb6, jb7, jb_next;
int answer_count;
int answer_fenshu;

public MyExGUI() {  
    // 创建菜单  
    jm = new JMenuBar();

    menu = new JMenu("文件(F)");  
    menu.setMnemonic('f'); // 助记符

    build = new JMenu("新建");

    file = new JMenuItem("文件");  
    project = new JMenuItem("答题");  
    item1 = new JMenuItem("保存(S)");  
    item2 = new JMenuItem("退出");

    answer = new JLabel("第 1 题");

    // 添加菜单项至菜单上  
    build.add(file);  
    build.add(project);

    menu.add(build);  
    menu.add(item1);  
    menu.add(item2);  
    menu.addSeparator();  
    // 将菜单加入至菜单栏  
    jm.add(menu);

    JPanel contentPanel = new JPanel();  
    contentPanel.setLayout(null);  
    JLabel daan = new JLabel("答案");  
    JLabel dengyu = new JLabel("=");  
    num\_answer = answer;  
    num\_answer.setFont(new Font("宋体", Font.BOLD, 22));  
    jb\_next = new JButton("下一题");  
    jta.setFont(new Font("宋体", Font.BOLD, 22));  
    jta\_answer.setFont(new Font("宋体", Font.BOLD, 22));  
    jb\_next.setFont(new Font("宋体", Font.BOLD, 22));  
    daan.setFont(new Font("宋体", Font.BOLD, 22));  
    dengyu.setFont(new Font("宋体", Font.BOLD, 22));

    contentPanel.add(num\_answer);  
    contentPanel.add(daan);  
    contentPanel.add(dengyu);  
    contentPanel.add(jta);

    contentPanel.add(jta\_answer);  
    contentPanel.add(answer\_all);  
    contentPanel.add(jb\_next);

    num\_answer.setBounds(90, 20, 130, 50);  
    daan.setBounds(250, 20, 90, 50);  
    jta.setBounds(50, 70, 150, 30);  
    dengyu.setBounds(205, 70, 20, 20);  
    jta\_answer.setBounds(230, 70, 100, 30);  
    jb\_next.setBounds(350, 70, 110, 30);  
    answer\_all.setBounds(50, 120, 400, 300);

    this.setJMenuBar(jm); // 添加菜单栏，不能设定位置，会自动放在最上部  
    this.add(contentPanel);

    this.setTitle("在线答题系统");  
    this.setSize(600, 500);  
    this.setVisible(true);  
    this.setDefaultCloseOperation(JFrame.EXIT\_ON\_CLOSE);  
    item1.addActionListener(new ActionListener() {  
        public void actionPerformed(ActionEvent arg0) {  
            FileOutputStream outSTr = null;  
            BufferedOutputStream Buff = null;  
            boolean flag = true;  
            File file;  
            // String test ;  
            do {  
                // test = "test"+count;

                String inputValue = JOptionPane.showInputDialog("Please input file name");  
                file = new File(inputValue + "test.txt");  
                if (!file.exists()) {  
                    // 创建文件  
                    try {

                        flag = file.createNewFile();

                    } catch (IOException e) {  
                        e.printStackTrace();

                    }  
                    flag = false;  
                } else {

                    JOptionPane.showMessageDialog(null, "该文件名已存在，请重新输入", "ERROR", JOptionPane.ERROR\_MESSAGE);  
                    flag = true;  
                }  
            } while (flag);  
            // 写入文件  
            String u\_answer;  
            try {  
                outSTr = new FileOutputStream(file);  
                Buff = new BufferedOutputStream(outSTr);  
                System.out.println("选择是后执行的代码" + user\_zongti.size() + user\_answer.size());  
                for (int i = 0; i < user\_zongti.size(); i++) {  
                    try {  
                        Buff.write(user\_zongti.get(i).getBytes());  
                        Buff.write("    ".getBytes());  
                        u\_answer = user\_answer.get(i);  
                        if (u\_answer.equals(""))  
                            u\_answer = "没有作答";

                        Buff.write(u\_answer.getBytes());  
                        Buff.write("\\r\\n".getBytes());  
                    } catch (IOException e) {  
                        e.printStackTrace();  
                        i--;  
                    }  
                }  
                Buff.flush();  
                Buff.close();

            } catch (IOException e) {  
                e.printStackTrace();  
            }  
            try {  
                outSTr.close();  
            } catch (IOException e) {  
                e.printStackTrace();  
            }  
            user\_zongti.clear();  
            user\_answer.clear();  
        }  
    });

    project.addActionListener(new ActionListener() {  
        public void actionPerformed(ActionEvent arg0) {  
            arithmetic art = new arithmetic();  
            true\_answer = art.list\_answer;  
            jta\_timu = art.list\_timu;  
            jta\_zong = art.list;  
            answer\_count = 1;  
            answer\_all.setText("");  
            for (int i = 0; i < art.list\_timu.size(); i++) {  
                user\_zongti.add(jta\_zong.get(i));  
                answer\_all.append(jta\_timu.get(i));  
                answer\_all.append("\\r\\n");  
            }  
            num\_answer.setText("第 " + answer\_count + " 题");  
            jta.setText(jta\_timu.get(answer\_count - 1));  
            answer\_count++;

        }  
    });  
    jb\_next.addActionListener(new ActionListener() {  
        public void actionPerformed(ActionEvent arg0) {  
            String temp;  
            temp = jta\_answer.getText();

            if (jta.getText().equals("")) {  
                JOptionPane.showMessageDialog(null, "错误,请导入题库", "错误", JOptionPane.ERROR\_MESSAGE);  
                return;  
            }  
            jta\_answer.setText("");  
            if (answer\_count <= 10) {  
                if (isInteger(temp)) {

                    user\_answer.add(temp);  
                    System.out.println("选择否后执行的代码" + temp + "user\_size" + user\_answer.size());  
                    num\_answer.setText("第 " + answer\_count + " 题");  
                    jta.setText(jta\_timu.get(answer\_count - 1));  
                    answer\_count++;  
                } else {  
                    JOptionPane.showMessageDialog(null, "错误", "请输入数字", JOptionPane.ERROR\_MESSAGE);  
                }  
            } else {  
                user\_answer.add(temp);  
                System.out.println("选择否后执行的代码" + temp + "user\_size" + user\_answer.size());  
                answer\_fenshu = 0;  
                for (int i = 0; i < user\_answer.size(); i++) {  
                    if (user\_answer.get(i).equals(true\_answer.get(i)))  
                        answer\_fenshu += 5;  
                }  
                user\_fenshu.add(answer\_fenshu);  
                Object\[\] options = { "是", "取消" };  
                int res = JOptionPane.showOptionDialog(null, "是否查看成绩", "答题完毕", JOptionPane.DEFAULT\_OPTION,  
                        JOptionPane.YES\_NO\_OPTION, null, options, options\[0\]);  
                if (res == JOptionPane.YES\_OPTION) {  
                    chart ct = new chart(user\_fenshu);  
                    ct.setVisible(true);

                } else {  
                    Object\[\] option = { "是", "取消" };  
                    int res1 = JOptionPane.showOptionDialog(null, "是否退出程序", "终止框", JOptionPane.DEFAULT\_OPTION,  
                            JOptionPane.YES\_NO\_OPTION, null, option, option\[0\]);

                    if (res1 == JOptionPane.YES\_OPTION) {  
                        dispose();  
                        System.exit(0);

                    } else {

                    }

                }

            }

        }  
    });

    item2.addActionListener(new ActionListener() {  
        public void actionPerformed(ActionEvent e) {  
            dispose();  
            System.exit(0);  
        }  
    });

}

public static boolean isInteger(String str) {  
    for (int i = str.length(); --i >= 0;) {  
        if (!Character.isDigit(str.charAt(i))) {  
            return false;  
        }  
    }  
    return true;  
}

}

MyExGUI

package ui_test;

public class Main {

public static void main(String\[\] args) {  
    MyExGUI lg = new MyExGUI();  
    //new MyExGUI();

}

}

Main

package ui_test;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Random;
import java.util.Scanner;

public class arithmetic {
ArrayList list = new ArrayList();
ArrayList list_timu = new ArrayList();
ArrayList list_answer = new ArrayList();

public arithmetic() {  
    FileOutputStream outSTr = null;  
    BufferedOutputStream Buff = null;  
    int number\_n = 10, count;

    ArrayList<String> list\_temp = new ArrayList<String>();  
    String\[\] operator = new String\[\] { "+", "-", "\*", "/" };

    Random rand = new Random();  
    File file1 = new File("test.txt");  
    if (file1.exists()) {  
        // 创建文件  
        try {  
            file1.createNewFile();  
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
    }

    while (number\_n > 0) {  
        int\[\] number\_temp = new int\[rand.nextInt(2) + 3\];  
        String\[\] str\_temp = new String\[number\_temp.length - 1\];  
        for (int i = 0; i < number\_temp.length; i++) {  
            if (i < number\_temp.length - 1) {  
                number\_temp\[i\] = rand.nextInt(100);  
                list\_temp.add(String.valueOf(number\_temp\[i\]));  
                str\_temp\[i\] = operator\[rand.nextInt(4)\];  
                list\_temp.add(str\_temp\[i\]);

            }

            else {  
                number\_temp\[i\] = rand.nextInt(100);  
                list\_temp.add(String.valueOf(number\_temp\[i\]));  
            }  
        }

        count = calculate\_RPN(produce\_RPN(list\_temp));  
        if (count != -1) {  
            list\_timu.add(transform\_string(list\_temp));  
            list\_answer.add(String.valueOf(count));  
            list\_temp.add(" = " + count);  
            list.add(transform\_string(list\_temp));  
            number\_n--;  
            list\_temp.clear();  
        } else  
            list\_temp.clear();  
        System.out.println(number\_n);

    }  
    try {  
        outSTr = new FileOutputStream(file1);  
        Buff = new BufferedOutputStream(outSTr);  
        for (int i = 0; i < list.size(); i++) {  
            try {  
                Buff.write(list.get(i).getBytes());  
                Buff.write("\\r\\n".getBytes());  
            } catch (IOException e) {  
                e.printStackTrace();  
                i--;  
            }  
        }  
        Buff.flush();  
        Buff.close();

    } catch (IOException e) {  
        e.printStackTrace();  
    }  
    // Buff.close();  
    try {  
        outSTr.close();  
    } catch (IOException e) {  
        e.printStackTrace();  
    }

    for (int i = 0; i < list.size(); i++) {  
        System.out.print(list.get(i));  
        System.out.println();  
    }  
    System.out.print("计算完毕！");

}

public static int calculate\_RPN(ArrayList<String> list\_temp) {  
    int i = 0, t;  
    double a = 0, b = 0;  
    String l\_temp;  
    Stack sk = new Stack(10);  
    for (t = 0; t < list\_temp.size(); t++) {  
        l\_temp = list\_temp.get(i++);  
        if (!isInteger(l\_temp)) {  
            b = sk.mypop();  
            a = sk.mypop();  
            switch (l\_temp) {  
            case "+":  
                sk.mypush(a + b);  
                break;  
            case "-":  
                if(!(a<b)) {  
                sk.mypush(a - b);  
                }  
                else  
                    return -1;  
                break;  
            case "\*":  
                sk.mypush(a \* b);  
                break;  
            case "/":  
                if (b == 0||a<b)  
                    return -1;  
                sk.mypush(a / b);  
                break;  
            }  
            System.out.println("st.mytop: " + sk.mypeek());  
        } else {  
            sk.mypush((double) Integer.parseInt(l\_temp));  
        }

    }  
    if (!sk.myisempty()) {  
        a = sk.mypop();  
        b = a - (int) a;  
        System.out.println("a:  " + a);  
        if (a > 0 && b == 0) {  
            return (int) a;  
        } else  
            return -1;  
    } else  
        return -1;

}

public static ArrayList<String> produce\_RPN(ArrayList<String> list\_temp) {  
    int t = 0, i = 0;  
    String tmp;  
    Tack mytack = new Tack(10);  
    ArrayList<String> lt\_temp = new ArrayList<String>();  
    while (true) {  
        tmp = list\_temp.get(i++);  
        if (isInteger(tmp)) {  
            lt\_temp.add(tmp);  
        } else {  
            if (mytack.myisempty()) {  
                mytack.mypush(tmp);  
            }

            else {  
                if (isCPriority(tmp, mytack.mypeek()))  
                    mytack.mypush(tmp);  
                else {  
                    lt\_temp.add(mytack.mypop());  
                    mytack.mypush(tmp);  
                }

            }  
        }  
        if (i >= list\_temp.size()) {  
            while (!mytack.myisempty())  
                lt\_temp.add(mytack.mypop());  
            System.out.println(transform\_string(list\_temp));  
            list\_temp = lt\_temp;  
            System.out.println(list\_temp);  
            return list\_temp;  
        }  
    }

}

public static boolean isInteger(String str) {  
    for (int i = str.length(); --i >= 0;) {  
        if (!Character.isDigit(str.charAt(i))) {  
            return false;  
        }  
    }  
    return true;  
}

public static boolean isCPriority(String str, String s) {  
    if ((str + s).equals("\*+") || (str + s).equals("\*-") || (str + s).equals("/+") || (str + s).equals("/-"))  
        return true;  
    else  
        return false;  
}

public static String transform\_string(ArrayList<String> list\_temp) {  
    String s = "";  
    for (int i = 0; i < list\_temp.size(); i++) {  
        s += list\_temp.get(i);  
    }  
    return s;

}

static class Stack {  
    int mytop;  
    double stk\[\];

    public Stack(int num) {  
        mytop = -1;  
        stk = new double\[num\];  
    }

    /\* 出栈 \*/  
    double mypop() {  
        double peek = stk\[mytop\];  
        mytop--;  
        return peek;  
    }

    /\* 入栈 \*/  
    void mypush(double x) {  
        mytop++;  
        stk\[mytop\] = x;

    }

    /\* 判空 \*/  
    Boolean myisempty() {  
        if (mytop == -1)  
            return true;  
        else  
            return false;  
    }

    /\* 取栈顶元素 \*/  
    double mypeek() {  
        double peek = stk\[mytop\];  
        return peek;  
    }

    /\* 栈大小 \*/  
    int mysize() {  
        return mytop + 1;  
    }  
}

static class Tack {  
    int mytop;  
    String tk\[\];

    public Tack(int num) {  
        mytop = -1;  
        tk = new String\[num\];  
    }

    /\* 出栈 \*/  
    String mypop() {  
        String peek = tk\[mytop\];  
        mytop--;  
        return peek;  
    }

    /\* 入栈 \*/  
    void mypush(String x) {  
        mytop++;  
        tk\[mytop\] = x;

    }

    /\* 判空 \*/  
    Boolean myisempty() {  
        if (mytop == -1)  
            return true;  
        else  
            return false;  
    }

    /\* 取栈顶元素 \*/  
    String mypeek() {  
        String peek = tk\[mytop\];  
        return peek;  
    }

    /\* 栈大小 \*/  
    int mysize() {  
        return mytop + 1;  
    }

}

}

arithmetic

package ui_test;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.util.ArrayList;
import java.util.Random;

import javax.swing.JFrame;

public class chart extends JFrame{
//绘制柱形统计图
ArrayList ran=new ArrayList();
public chart(ArrayList scores)
{
super();
getContentPane().setForeground(Color.CYAN);
setForeground(Color.CYAN);
setBackground(Color.CYAN);
for(int i=0;i<scores.size();i++)
{
ran.add(scores.get(i));
System.out.println(scores.get(i));
}

        setTitle("绘制柱形图");  
        setSize(600, 400);  
        setDefaultCloseOperation(JFrame.EXIT\_ON\_CLOSE);  
    }  
    @Override  
    public void paint(Graphics g){  
        int Width = getWidth();  
        int Height = getHeight();  
        int leftMargin = 20;//柱形图左边界  
        int topMargin = 50;//柱形图上边界  
        Graphics2D g2 = (Graphics2D) g;  
        g2.setColor(Color.WHITE);//绘制白色背景  
        g2.fillRect(0, 0, Width, Height-100);//绘制矩形图  
        g2.setColor(Color.black);  
         for(int i=0;i<=10;i++)  
         {  
             //绘制灰色横线和百分比  
             g2.drawString((100-10\*i)+" ", 15, topMargin+30\*i);  
             g2.drawLine(10, topMargin+30\*i, Width, topMargin+30\*i);//绘制灰色横线  
         }  
         g2.setColor(Color.RED);  
         for(int i=0;i<=ran.size();i++)  
         {  
             //绘制柱形图  
             int step = (i+1)\*40;//设置每个柱形图的水平间隔为40  
             //绘制矩形  
             g2.fillRoundRect(leftMargin+step\*2-5,(100-ran.get(i))\*3+50, 40, 300-(100-ran.get(i))\*3, 40, 10);  
             //列出测试轮数  
             g2.drawString("第"+(i+1)+"轮", leftMargin+step\*2, 380);  
         }  
     }

}

chart

运行结果：

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