本文实例讲述了Java Swing实现简单的体重指数(BMI)计算器功能。分享给大家供大家参考，具体如下：
BMI，Body Mass Index，身体质量指数，是用体重公斤数 除以 身高米数平方得出的，是目前国际上常用的衡量人体胖瘦程度以及是否健康的一个标准。
而本文通过运用Java Swing实现了一个简单的BMI计算器。虽然现在网页上也有相应的网页应用，但是能够做出这个计算器来，还是有点成就感的，希望自己以后做出更多比这个好的应用。
最终运行效果：
功能：可以选择三个标准：中国、亚洲、WHO，计算结果稍有不同
计算公式：BMI = weight / (height*height) 即 体重公斤数 除以 身高米数平方
package WeightIndex;import javax.swing.*;import javax.swing.border.EmptyBorder;import java.awt.*;import java.awt.event.*;import java.text.DecimalFormat;import java.util.regex.*;public class WeightIndex extends JFrame { /** * */ private static final long serialVersionUID = 1L; private JPanel contentPane; private JLabel titleLabel; private JPanel contentPanel; private JButton submitButton; private ButtonGroup bg; private JPanel sexPanel; private JRadioButton ChinaRadio; private JRadioButton AsiaRadio; private JRadioButton WHORadio; private JPanel whPanel; private JLabel heightLabel; private JLabel weightLabel; private JTextField heightText; private JTextField weightText; private JPanel consolePanel; private JLabel consoleLabel; private JTextField consoleText; private double weight; private double height; private double BMI; /** * Launch the application. */ public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { try { WeightIndex frame = new WeightIndex(); frame.pack(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the frame. */ public WeightIndex() { setTitle("武林网 - 身高体重指数计算器v1.0"); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setBounds(100, 100, 450, 300); //主容器 contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); contentPane.setLayout(new BorderLayout(0, 0)); setContentPane(contentPane); //标题，主容器北 titleLabel = new JLabel("身高体重指数计算器"); titleLabel.setHorizontalAlignment(SwingConstants.CENTER); contentPane.add(titleLabel, BorderLayout.NORTH); //存放选项的panel，主容器中 contentPanel = new JPanel(); contentPanel.setLayout(new BorderLayout()); contentPane.add(contentPanel,BorderLayout.CENTER); //提交按钮，主容器南 submitButton = new JButton("计算"); contentPane.add(submitButton, BorderLayout.SOUTH); //存放性别选择的panel，选项北 bg = new ButtonGroup(); sexPanel = new JPanel(); sexPanel.setLayout(new FlowLayout()); contentPanel.add(sexPanel,BorderLayout.NORTH); ChinaRadio = new JRadioButton("中国标准"); ChinaRadio.setSelected(true); AsiaRadio = new JRadioButton("亚洲标准"); WHORadio = new JRadioButton("WHO（世界卫生组织）标准"); bg.add(ChinaRadio); bg.add(AsiaRadio); bg.add(WHORadio); sexPanel.add(ChinaRadio); sexPanel.add(AsiaRadio); sexPanel.add(WHORadio); //存放身高体重的panel，选项中 whPanel = new JPanel(); whPanel.setLayout(new FlowLayout()); contentPanel.add(whPanel,BorderLayout.CENTER); heightLabel = new JLabel("身高（米/m）："); weightLabel = new JLabel("体重（千克/kg）："); heightText = new JTextField(10); heightText.setToolTipText("请输入身高"); weightText = new JTextField(10); weightText.setToolTipText("请输入体重"); whPanel.add(heightLabel); whPanel.add(heightText); whPanel.add(weightLabel); whPanel.add(weightText); //结果 consolePanel = new JPanel(); consolePanel.setLayout(new FlowLayout()); consoleLabel = new JLabel("你的身体质量指数为："); consoleText = new JTextField(28); consoleText.setEditable(false); consolePanel.add(consoleLabel); consolePanel.add(consoleText); contentPanel.add(consolePanel,BorderLayout.SOUTH); submitButton.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent e) { String hstr = heightText.getText(); String wstr = weightText.getText(); Pattern pattern = Pattern.compile("^[0-9]+(.[0-9]+)?$"); Matcher hisNum = pattern.matcher(hstr); Matcher wisNum = pattern.matcher(wstr); boolean acc = true; if( !hisNum.matches()|| !wisNum.matches()){ acc = false; } if(acc) { height = Double.parseDouble(hstr); weight = Double.parseDouble(wstr); BMI = weight / (height*height); DecimalFormat df = new DecimalFormat("#.0"); String out = ""; if(ChinaRadio.isSelected()) { if(BMI<18.5) out = "偏瘦，瘦骨嶙峋的，多吃点吧！"; else if(BMI<23.9) out = "正常，棒棒哒！"; else if(BMI<28) out = "偏胖，你胖你就运动减肥！"; else if(BMI>=28) out = "肥胖，现在减肥来的及！"; else out ="外星人派来的你哦，请重新输入！"; } else if(AsiaRadio.isSelected()) { if(BMI<18.5) out = "偏瘦，瘦骨嶙峋的，多吃点吧！"; else if(BMI<22.9) out = "正常，棒棒哒！"; else if(BMI<24.9) out = "偏胖，你胖你就运动减肥！"; else if(BMI<30) out = "肥胖，现在减肥来的及！"; else if(BMI>=30) out = "重度肥胖，不是一般人，赶紧减肥吧！"; else out ="外星人派来的你哦，请重新输入！"; } else { if(BMI<18.5) out = "偏瘦，瘦骨嶙峋的，多吃点吧！"; else if(BMI<24.9) out = "正常，棒棒哒！"; else if(BMI<29.9) out = "偏胖，你胖你就运动减肥！"; else if(BMI<34.9) out = "肥胖，现在减肥来的及！"; else if(BMI<39.9) out = "重度肥胖，不是一般人，赶紧减肥吧！"; else if(BMI>=40) out = "极重度肥胖,那可能得去医院看看咯！"; else out ="外星人派来的你哦，请重新输入！"; } consoleText.setText("你的指数为："+df.format(BMI)+"，你的健康状况为："+out); } } }); }}更多关于java算法相关内容感兴趣的读者可查看本站专题：《Java数据结构与算法教程》、《Java操作DOM节点技巧总结》、《Java文件与目录操作技巧汇总》和《Java缓存操作技巧汇总》
希望本文所述对大家java程序设计有所帮助。