本文实例为大家分享了java利用数组随机抽取幸运观众的具体代码，供大家参考，具体内容如下

思想：

首先将所有观众姓名生成数组，然后获取数组元素的总数量，再在数组元素中随机抽取元素的下标，根据元素的下标得到幸运观众的名字。

import java.awt.BorderLayout;

import java.awt.EventQueue;

import javax.swing.JFrame;

import javax.swing.JPanel;

import javax.swing.border.EmptyBorder;

import javax.swing.JTextField;

import javax.swing.JTextArea;

import javax.swing.JScrollPane;

import javax.swing.border.TitledBorder;

import javax.swing.JButton;

import java.awt.event.KeyAdapter;

import java.awt.event.KeyEvent;

import java.awt.event.ActionListener;

import java.awt.event.ActionEvent;

import javax.swing.UIManager;

import java.awt.Color;

public class ArrayExample extends JFrame {

private JPanel contentPane;

private JTextField nameField;

private JTextArea personnelArea;

private JTextArea resultArea;

/**@auther 葆宁

* 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() {

setTitle("\u5229\u7528\u6570\u7EC4\u968F\u673A\u62BD\u53D6\u5E78\u8FD0\u89C2\u4F17");

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

setBounds(100, 100, 498, 300);

contentPane = new JPanel();

contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));

setContentPane(contentPane);

contentPane.setLayout(null);

JPanel panel = new JPanel();

panel

.setBorder(new TitledBorder(

null,

"\u8F93\u5165\u5728\u573A\u89C2\u4F17\u59D3\u540D\u6309\u56DE\u8F66",

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,

"\u9009\u53D6\u89C2\u4F17\u4EBA\u5458\uFF1A",

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("\u62BD\u53D6");

button.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

do_button_actionPerformed(e);

}

});

button.setBounds(407, 164, 63, 25);

contentPane.add(button);

JButton button_1 = new JButton("\u9000\u51FA");

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$s\n恭喜%1$s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过期的酸奶二十箱。";

// 为中奖信息添加人员参数

String info = String.format(formatArg, personnelArray[index]);

resultArea.setText(info);// 在文本域显示中间信息

}

protected void do_button_1_actionPerformed(ActionEvent e) {

dispose();

}

}

效果图：

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。