目录

七、组件综合练习

7.1 练习-为空判断.

7.2 练习-数字校验.

7.3 练习-账号密码验证.

7.4 练习-黄鹤.

7.5 练习-复利计算器.

7.6 练习-进度条.

7.7 练习-显示文件夹复制进度条.

package gui;import javax.swing.*;
import java.awt.*;
import java.sql.*;public class TestGUI {public static void main(String[] args){JFrame jf = new JFrame("LOL");jf.setSize(416,300);jf.setLocation(500,300);jf.setLayout(null);JPanel jp = new JPanel();jp.setBounds(8,8,400,300);jp.setLayout(new FlowLayout());JTextField content = new JTextField("");content.setPreferredSize(new Dimension(80,30));JButton jb = new JButton("检测");jb.setSize(50,30);jb.addActionListener(e->{String cont = content.getText();if(cont.isEmpty()){JOptionPane.showMessageDialog(jf,"文本内容为空");}else{JOptionPane.showMessageDialog(jf,"文本内容为:"+cont);}});jp.add(content);jp.add(jb);jf.add(jp);jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);jf.setVisible(true);}}

public static boolean isNumeric(String str){Pattern pattern = Pattern.compile("[0-9]*");return pattern.matcher(str).matches();
}

package gui;import javax.swing.*;
import java.awt.*;
import java.sql.*;
import java.util.regex.Pattern;public class TestGUI {public static boolean isNumeric(String str){Pattern pattern = Pattern.compile("[0-9]*");return pattern.matcher(str).matches();  }public static void main(String[] args){JFrame jf = new JFrame("LOL");jf.setSize(416,300);jf.setLocation(500,300);jf.setLayout(null);JPanel jp = new JPanel();jp.setBounds(8,8,400,300);jp.setLayout(new FlowLayout());JTextField content = new JTextField("");content.setPreferredSize(new Dimension(80,30));JButton jb = new JButton("检测");jb.setSize(50,30);jb.addActionListener(e->{String cont = content.getText();if(cont.isEmpty()) {JOptionPane.showMessageDialog(jf,"输入框内容为空");}else{if(isNumeric(cont))JOptionPane.showMessageDialog(jf,"输入框内容是数字:"+cont);elseJOptionPane.showMessageDialog(jf,"输入框内容不是数字");}});jp.add(content);jp.add(jb);jf.add(jp);jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);jf.setVisible(true);}}

package gui;import javax.swing.*;
import java.awt.*;
import java.sql.*;public class TestGUI {private static String url = "jdbc:mysql://127.0.0.1:3306/how2java?characterEncoding=UTF-8";private static String Name = "root";private static String Pwd = "root";public static void main(String[] args){try {Class.forName("com.mysql.jdbc.Driver");}catch (Exception e){e.printStackTrace();}JFrame jf = new JFrame("register");jf.setSize(416,300);jf.setLocation(500,300);jf.setLayout(null);JPanel jp1 = new JPanel();jp1.setBounds(8,8,400,30);jp1.setLayout(new FlowLayout());JLabel name = new JLabel("账号：");JTextField EnterName = new JTextField("");EnterName.setPreferredSize(new Dimension(80,30));JLabel password = new JLabel("密码：");JPasswordField EnterPwd = new JPasswordField("");EnterPwd.setPreferredSize(new Dimension(80,30));jp1.add(name);jp1.add(EnterName);jp1.add(password);jp1.add(EnterPwd);JPanel jp2 = new JPanel();jp2.setBounds(8,46,400,30);jp2.setLayout(new FlowLayout());JButton jb = new JButton("登录");jb.setSize(50,30);jb.addActionListener(e->{if(!EnterName.getText().isEmpty() && !EnterPwd.getText().isEmpty()){try(Connection conn = DriverManager.getConnection(url,Name,Pwd)){String str = "select * from user where name = ? and password = ?";PreparedStatement ps = conn.prepareStatement(str);ps.setString(1,EnterName.getText());ps.setString(2,EnterPwd.getText());ResultSet rs = ps.executeQuery();if(rs.next()){JOptionPane.showMessageDialog(jf,"登录成功");}else{JOptionPane.showMessageDialog(jf,"账户名或者密码错误");}}catch (Exception ee){ee.printStackTrace();}}});jp2.add(jb);jf.add(jp1);jf.add(jp2);jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);jf.setVisible(true);}}

package gui;import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.regex.Pattern;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.JTextField;public class TestGUI {public static boolean isNumeric(String str){Pattern pattern = Pattern.compile("[0-9]*");return pattern.matcher(str).matches();
}public static void main(String[] args) {JFrame f=new JFrame("LOL");f.setSize(400,500);f.setLocation(500,500);f.setLayout(null);JPanel p1=new JPanel();p1.setBounds(0, 0, 90, 170);p1.setLayout(new FlowLayout(FlowLayout.LEFT,10,18));JPanel p2=new JPanel();p2.setBounds(80, 0, 110, 170);p2.setLayout(new FlowLayout(FlowLayout.LEFT,20,15));JPanel p3=new JPanel();p3.setBounds(190, 0, 80, 170);p3.setLayout(new FlowLayout(FlowLayout.LEFT,10,18));JPanel p4=new JPanel();p4.setBounds(260, 0, 110, 170);p4.setLayout(new FlowLayout(FlowLayout.LEFT,20,15));JLabel l1=new JLabel("地名：");JLabel l2=new JLabel("公司类型：");JLabel l3=new JLabel("公司名称：");JLabel l4=new JLabel("老板名称：");JLabel l5=new JLabel("金额：");JLabel l6=new JLabel("产品：");JLabel l7=new JLabel("价格计量单位：");JTextField tf1=new JTextField();tf1.setPreferredSize(new Dimension(90,22));JTextField tf2=new JTextField();tf2.setPreferredSize(new Dimension(90,22));JTextField tf3=new JTextField();tf3.setPreferredSize(new Dimension(90,22));JTextField tf4=new JTextField();tf4.setPreferredSize(new Dimension(90,22));JTextField tf5=new JTextField();tf5.setPreferredSize(new Dimension(90,22));JTextField tf6=new JTextField();tf6.setPreferredSize(new Dimension(90,22));JTextField tf7=new JTextField();tf7.setPreferredSize(new Dimension(90,22));p1.add(l1);p1.add(l3);p1.add(l5);p1.add(l7);p2.add(tf1);p2.add(tf3);p2.add(tf5);p2.add(tf7);p3.add(l2);p3.add(l4);p3.add(l6);p4.add(tf2);p4.add(tf4);p4.add(tf6);f.add(p1);f.add(p2);f.add(p3);f.add(p4);JButton b=new JButton("生成");b.setBounds(160,170,80,30);JTextArea ta=new JTextArea();ta.setBounds(10, 220, 365, 230);ta.setLineWrap(true);b.addActionListener(new ActionListener() {public void actionPerformed(ActionEvent e) {if (!tf1.getText().isEmpty()&&!tf2.getText().isEmpty()&&!tf3.getText().isEmpty()&&!tf4.getText().isEmpty()&&!tf5.getText().isEmpty()&&!tf6.getText().isEmpty()&&!tf7.getText().isEmpty()){if (isNumeric(tf5.getText())){String str=tf1.getText()+"最大"+tf2.getText()+tf3.getText()+"倒闭了，"+ "王八蛋老板"+tf4.getText()+"吃喝嫖赌，欠下了"+tf5.getText()+"，"+ "带着他的小姨子跑了!我们没有办法，拿着"+tf6.getText()+"抵工资!"+ "原价都是一"+tf7.getText()+"多、两"+tf7.getText()+"多、三"+tf7.getText()+"多的"+tf6.getText()+"，"+ "现在全部只卖二十块，统统只要二十块!"+tf4.getText()+"王八蛋，"+ "你不是人!我们辛辛苦苦给你干了大半年，你不发工资，你还我血汗钱，还我血汗钱!";ta.setText(str);}elseJOptionPane.showMessageDialog(f, "金额不是数字!");}elseJOptionPane.showMessageDialog(f, "有内容为空!");}});f.add(b);f.add(ta);f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);f.setVisible(true);}}

package gui;import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;public class TestGUI {public static void main(String[] args) {JFrame f=new JFrame("LOL");f.setSize(420,400);f.setLayout(null);f.setLocation(450,500);JPanel p1=new  JPanel();p1.setBounds(0,0,100,120);p1.setLayout(new FlowLayout(FlowLayout.LEFT,10,11));JPanel p2=new  JPanel();p2.setBounds(135,0,130,120);p2.setLayout(new FlowLayout(FlowLayout.LEFT,10,9));JPanel p3=new  JPanel();p3.setBounds(270,0,25,120);p3.setLayout(new FlowLayout(FlowLayout.LEFT,10,11));JPanel p4=new JPanel();p4.setBounds(0,140,400,35);p4.setLayout(new FlowLayout());JPanel p5=new  JPanel();p5.setBounds(0,195,70,120);p5.setLayout(new FlowLayout(FlowLayout.LEFT,10,11));JPanel p6=new  JPanel();p6.setBounds(135,195,130,120);p6.setLayout(new FlowLayout(FlowLayout.LEFT,10,9));JPanel p7=new  JPanel();p7.setBounds(270,195,25,120);p7.setLayout(new FlowLayout(FlowLayout.LEFT,10,11));JLabel l1=new JLabel("起始资金");JLabel l2=new JLabel("每年收益");JLabel l3=new JLabel("复利年数");JLabel l4=new JLabel("每年追加资金");JLabel l5=new JLabel("￥");JLabel l6=new JLabel("%");JLabel l7=new JLabel("年");JLabel l8=new JLabel("￥");JLabel l9=new JLabel("本金和");JLabel l10=new JLabel("利息和");JLabel l11=new JLabel("本息和");JLabel l12=new JLabel("￥");JLabel l13=new JLabel("￥");JLabel l14=new JLabel("￥");JTextField tf1=new JTextField();tf1.setPreferredSize(new Dimension(120,20));JTextField tf2=new JTextField();tf2.setPreferredSize(new Dimension(120,20));JTextField tf3=new JTextField();tf3.setPreferredSize(new Dimension(120,20));JTextField tf4=new JTextField();tf4.setPreferredSize(new Dimension(120,20));JTextField tf5=new JTextField();tf5.setPreferredSize(new Dimension(120,20));JTextField tf6=new JTextField();tf6.setPreferredSize(new Dimension(120,20));JTextField tf7=new JTextField();tf7.setPreferredSize(new Dimension(120,20));JButton b=new JButton("计算");b.setPreferredSize(new Dimension(80,30));b.addActionListener(new ActionListener() {public void actionPerformed(ActionEvent e) {int initMoney,year,each;float rate;initMoney=Integer.valueOf(tf1.getText());//获取起始资金rate=(Integer.valueOf(tf2.getText()));//获取每年收益year=Integer.valueOf(tf3.getText());//获取复利年数each=Integer.valueOf(tf4.getText());//每年追加资金int F1=(year-1)*each+initMoney;//本金和int F3=(int) (each* fuli(  (1+rate/100),(year-1)) + initMoney*p( (1+rate/100) ,year));//本息和int F2=F3-F1;//利息和tf5.setText(clauses(F1));tf6.setText(clauses(F2));tf7.setText(clauses(F3));}});p1.add(l1);p1.add(l2);p1.add(l3);p1.add(l4);p2.add(tf1);p2.add(tf2);p2.add(tf3);p2.add(tf4);p3.add(l5);p3.add(l6);p3.add(l7);p3.add(l8);p4.add(b);p5.add(l9);p5.add(l10);p5.add(l11);p6.add(tf5);p6.add(tf6);p6.add(tf7);p7.add(l12);p7.add(l13);p7.add(l14);f.add(p1);f.add(p2);f.add(p3);f.add(p4);f.add(p5);f.add(p6);f.add(p7);f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);f.setVisible(true);}public static float p(float base,int power) {if(1==power)return base;if(0==power)return 1;float result = base;for(int i=0;i<power-1;i++) {result = result*base;}return result;}public static float fuli(float rate,int year) {float result = 0;for(int i=year;i>0;i--) {result +=p(rate,i);}return result;}protected static String clauses(int f1) {return String.format("%,d", f1);}
}

package gui;import java.awt.FlowLayout;import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JProgressBar;public class TestGUI {public static void main(String[] args) {JFrame f=new JFrame("LOL");f.setSize(400,300);f.setLocation(500,500);f.setLayout(new FlowLayout(FlowLayout.CENTER,100,20));JProgressBar pb=new JProgressBar();pb.setMaximum(100);Thread t=new Thread() {public void run() {try {for (int i = 0; i <=100; i++) {if(i<40) {pb.setValue(i);Thread.sleep(10);}if(i<60&&i>40) {pb.setValue(i);Thread.sleep(100);}if(i<80&&i>60) {pb.setValue(i);Thread.sleep(200);}if(i<100&&i>80) {pb.setValue(i);Thread.sleep(400);}if(i==100) {pb.setValue(0);i = 0;JOptionPane.showMessageDialog(f, "下载失败！点击重试！");}}} catch (InterruptedException e) {e.printStackTrace();}}};JButton b=new JButton("开始下载");b.addActionListener(e-> t.start());pb.setStringPainted(true);f.add(pb);f.add(b);f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);f.setVisible(true);}}

package gui;import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
import javax.swing.JTextField;public class TestGUI {static long allFileSize = 0; // 所有需要复制的文件大小static long currentFileSizeCopied = 0;// 已复制的文件总大小public static void main(String[] args) {JFrame f=new  JFrame("复制文件");f.setSize(400,200);f.setLocation(500,500);f.setLayout(null);JPanel p1=new JPanel();p1.setBounds(0,0,400,40);p1.setLayout(new FlowLayout(FlowLayout.CENTER,10,10));JLabel l1=new JLabel("源文件地址：");JLabel l2=new JLabel("复制到：");JTextField tf1=new JTextField();tf1.setPreferredSize(new Dimension(80,30));tf1.setText("C:\\迅雷下载");JTextField tf2=new JTextField();tf2.setText("C:\\Users\\LH\\Desktop\\迅雷下载");tf2.setPreferredSize(new Dimension(80,30));p1.add(l1);p1.add(tf1);p1.add(l2);p1.add(tf2);JButton b=new JButton("开始复制");JProgressBar pg=new JProgressBar();pg.setMaximum(100);pg.setValue(0);pg.setStringPainted(true);JPanel p2=new JPanel();p2.setBounds(0,40,400,50);p2.setLayout(new FlowLayout(FlowLayout.CENTER,10,10));JLabel l3=new JLabel("文件复制进度：");p2.add(b);p2.add(l3);p2.add(pg);f.add(p1);f.add(p2);f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);f.setVisible(true);calclateAllFilesize(new File(tf1.getText()));b.addActionListener(new ActionListener() {public void actionPerformed(ActionEvent e) {String A=tf1.getText();String B=tf2.getText();new Thread(() -> copyFolder(A,B)).start();b.setEnabled(false);}public void copyFolder(String srcFolder, String destFolder){File sf = new File(srcFolder);File df = new File(destFolder);if (!sf.exists())return;if (!sf.isDirectory())return;if (df.isFile())return;if (!df.exists())df.mkdirs();//            创建文件引用集合File[] f = sf.listFiles();
//            创建文件名称集合String[] name = sf.list();
//            for读出for(int i=0;i<f.length;i++) {
//                如果不是目录则执行if(!f[i].isDirectory()) {
//                    将源文件写入目标文件之中copyFile(f[i].getAbsolutePath(), new File(df+"/"+name[i]).getAbsolutePath());currentFileSizeCopied += f[i].length();double current = (double) currentFileSizeCopied / (double) allFileSize;int progress = (int) (current * 100);pg.setValue(progress);if(progress==100) {JOptionPane.showMessageDialog(p2, "复制完毕");b.setEnabled(true);}}else {
//                    反之则先创建父目录,再在将源文件写入目标文件之中new File(df+"/"+name[i]).mkdirs();copyFolder(f[i].getAbsolutePath(), new File(df+"/"+name[i]).getAbsolutePath());}}}//  文件写入public void copyFile(String srcFolder, String destFolder) {try(BufferedReader br = new BufferedReader(new FileReader(srcFolder));PrintWriter pw = new PrintWriter(new FileWriter(destFolder))) {while(true) {String str = br.readLine();if(str==null)break;pw.println(str);}} catch (IOException e) {e.getStackTrace();}}});}public static void calclateAllFilesize(File file) {if (file.isFile()) {allFileSize += file.length();}if (file.isDirectory()) {File[] fs = file.listFiles();for (File f : fs) {calclateAllFilesize(f);}}}}