从一组姓名中随机抽取幸运观众的代码实现 (Java经典编程案例)

从一组姓名中随机抽取幸运观众的代码实现 :

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.border.EmptyBorder;
import javax.swing.border.TitledBorder;

public class ArrayExample extends JFrame {

private static final long serialVersionUID = -2577935223412903226L;
private JPanel contentPane;
private JTextField nameField;
private JTextArea personnelArea;
private JTextArea resultArea;

/**
* Launch the application.
*/
public static void main(String[] args) {
try {
UIManager.setLookAndFeel("com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel");
} catch (Throwable e) {
e.printStackTrace();
}
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
ArrayExample frame = new ArrayExample();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}

/**
* Create the frame.
*/
public ArrayExample() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 498, 300);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
setTitle("利用数组随机抽取幸运观众");
contentPane.setLayout(null);

JPanel panel = new JPanel();
panel
.setBorder(new TitledBorder(
null,
"请输入姓名 再按回车",
TitledBorder.LEADING, TitledBorder.TOP, null,
new Color(59, 59, 59)));
panel.setBounds(10, 10, 174, 242);
contentPane.add(panel);
panel.setLayout(new BorderLayout(0, 5));

nameField = new JTextField();
nameField.addKeyListener(new KeyAdapter() {
@Override
public void keyPressed(KeyEvent e) {
do_textField_keyPressed(e);
}
});
panel.add(nameField, BorderLayout.NORTH);
nameField.setColumns(10);

JScrollPane scrollPane = new JScrollPane();
panel.add(scrollPane);

personnelArea = new JTextArea();
personnelArea.setEditable(false);
scrollPane.setViewportView(personnelArea);

JPanel panel_1 = new JPanel();
panel_1.setBorder(new TitledBorder(null,
"选取观众人员：",
TitledBorder.LEADING, TitledBorder.TOP, null, new Color(59, 59,
59)));
panel_1.setBounds(183, 10, 219, 242);
contentPane.add(panel_1);
panel_1.setLayout(new BorderLayout(0, 0));

JScrollPane scrollPane_1 = new JScrollPane();
panel_1.add(scrollPane_1);

resultArea = new JTextArea();
resultArea.setEditable(false);
resultArea.setLineWrap(true);
scrollPane_1.setViewportView(resultArea);

JButton button = new JButton("抽取");
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
do_button_actionPerformed(e);
}
});
button.setBounds(407, 164, 63, 25);
contentPane.add(button);

JBut
2167c
ton button_1 = new JButton("退出");
button_1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
do_button_1_actionPerformed(e);
}
});
button_1.setBounds(407, 215, 63, 25);
contentPane.add(button_1);
}

protected void do_textField_keyPressed(KeyEvent e) {
if (e.getKeyChar() != '\n')// 不是回车字符不做处理
return;
String name = nameField.getText();
if (name.isEmpty())// 如果文本框没有字符串不做处理
return;
personnelArea.append(name + "\n");// 把输入人名与回车符添加到人员列表
nameField.selectAll();// 选择文本框所有字符
}

protected void do_button_actionPerformed(ActionEvent e) {
String perstring = personnelArea.getText();// 获取人员列表文本
String[] personnelArray = perstring.split("\n{1,}");// 获取人员数组
int index = (int) (Math.random() * personnelArray.length);// 生成随机数组索引
// 定义包含格式参数的中奖信息
String formatArg = "本次抽取观众人员：\n\t%1$s\n恭喜%1$5s成为本次观众抽奖的大奖得主。"
+ "\n\n我们将为%1$s**颁发：\n\t宝马车一辆！！。";
// 为中奖信息添加人员参数
String info = String.format(formatArg, personnelArray[index]);
resultArea.setText(info);// 在文本域显示中奖信息
}

protected void do_button_1_actionPerformed(ActionEvent e) {
dispose();
}
}