《Java语言程序设计》专业实习任务书二

《Java语言程序设计》专业实习任务（二）一、设计目的：本次设计是对教材第7章～第17章的总结。

涉及到的主要知识点有：GUI设计、事件处理、I/O处理和JDBC。

设计的目的在于掌握Java的基本原理、设计方法和使用规则；利用Java提供的事务处理机制，合理选择类和类提供的方法，进行应用程序的初步设计。

二、设计题目：学生信息存放在数据库Student.mdb中，信息包括：学号、姓名、性别、年龄、专业。

系统包括查询、添加、删除、更新和退出系统五个功能。

主界面运行如下：1.功能描述①单击“查询”按钮，可以查询数据库中的学生信息，并将学生信息显示在JPanel中。

运行界面如下：②单击“增加”按钮，可以为数据库表中添加一条学生信息。

运行界面如下：③单击“删除”按钮，可以删除数据库表中的学生信息。

运行界面如下：⑷单击“更新”按钮，可以更新数据库表中指定学号的学生信息。

运行界面如下：要求：学号必须是数字字符串，长度不能大于10；姓名长度不能大于10，专业长度不能大于25。

⑸单击“退出系统”按钮，从整个应用系统中退出。

2.题目要求①根据题目要求建立数据库。

②完成程序段⑴～⒃的编写，使其系统各功能模块能够正常运行。

③回答问题①～⑧。

3.提示信息①Statement createStatement(int resultSetType,int resultSetConcurrency)throws SQLExceptionresultSetType：结果集类型，它是ResultSet.TYPE_FORWARD_ONL Y、ResultSet.TYPE_SCROLL_INSENSITIVE 或ResultSet.TYPE_SCROLL_SENSITIVE 之一；resultSetConcurrency：并发类型；它是ResultSet.CONCUR_READ_ONL Y 或ResultSet.CONCUR_UPDATABLE 之一；②update 语句：update 表名set 字段名=值,字段名=值,……where 条件4.程序清单①StudentManager.javapackage sms;import java.awt.Dimension;import java.awt.FlowLayout;import java.awt.Font;import java.awt.GridLayout;import java.awt.Toolkit;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JPanel;import java.awt.Color;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;public class StudentManager extends JFrame{private JLabel lbl1;private JButton selBtn,addBtn,delBtn,updBtn;private JButton exitBtn;private JPanel panel ;public StudentManager (){super("学生管理系统");// 定义出现的组件：由上而下，自左致右lbl1 = new JLabel("学生管理系统",JLabel.CENTER);lbl1.setFont(new Font("黑体",Font.BOLD,35));selBtn = new JButton("查询");addBtn = new JButton("添加");delBtn = new JButton("删除");updBtn = new JButton("更新");exitBtn=new JButton("退出系统");// 定义容器panel = new JPanel();//为容器设置布局，并将组件添加到容器中FlowLayout flow = new FlowLayout();panel.setLayout(flow);panel.add(selBtn);panel.add(addBtn);panel.add(delBtn);panel.add(updBtn);panel.add(exitBtn);//为按钮添加监听事件selBtn.addActionListener(new ButtonEvent());addBtn.addActionListener(new ButtonEvent());delBtn.addActionListener(new ButtonEvent());updBtn.addActionListener(new ButtonEvent());exitBtn.addActionListener(new ActionListener(){ //完成语句⑴：退出应用系统的功能});//为applet设置布局，并将组件添加到applet中GridLayout grid = new GridLayout(2,1);this.setLayout(grid);this.add(lbl1);this.add(panel);//设置applet的大小this.setSize(400,300);this.setVisible(true);//问题1：Toolkit的作用是什么？Toolkit tool = this.getToolkit();Dimension dim = tool.getScreenSize();this.setLocation(dim.width/3,dim.height/3);this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);validate();}public static void main(String[] args){new StudentManager();}}②DatabaseConnection.javapackage sms;//完成语句⑵：导入该类中操作数据库的相关类包public class DatabaseConnection {public static Connection getConnection(String dataSource , String user , String password){ Connection conn = null;try {String driverName = "sun.jdbc.odbc.JdbcOdbcDriver";//完成语句⑶：加载数据库驱动} catch (ClassNotFoundException e) {e.printStackTrace();}try {//完成语句⑷：通过getConnection()方法的参数获取数据库连接赋给conn } catch (SQLException e) {e.printStackTrace();}return conn;}}③SelFrame.javapackage sms;import java.awt.BorderLayout;import java.awt.Color;import java.awt.FlowLayout;import java.awt.GridLayout;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.awt.event.FocusEvent;import java.awt.event.FocusListener;//完成语句⑸：导入该类中操作数据库的相关类包import javax.swing.*;public class SelFrame extends JFrame implements ActionListener,FocusListener { private Connection conn = null;private Statement stmt = null;private ResultSet rs = null;private int recordCount=0;JLabel lbl1 = null;JLabel lbl2 = null;JTextField tf1 = null;JTextField tf2 = null;JButton selBtn= null;JPanel p1 = null;JPanel p2 = null;JPanel p3 = null;JPanel resultPanel = null;JScrollPane scroll = null;JPanel split = null;JPanel[] p3_1=null;JTextField[] tf3_1 = null;JTextField[] tf4_1 = null;JTextField[] tf5_1 = null;JTextField[] tf6_1 = null;JTextField[] tf7_1 = null;public static int test=1;public SelFrame(){super("学生信息查询");//定义组件：从上到下，从左到右lbl1 = new JLabel("姓名：",10);lbl2 = new JLabel("专业：",10);tf1 = new JTextField(20);tf2 = new JTextField(20);selBtn=new JButton("查询");selBtn.addActionListener(this);JLabel lbl3 = new JLabel("学号",JLabel.CENTER);JLabel lbl4 = new JLabel("姓名",JLabel.CENTER);JLabel lbl5 = new JLabel("年龄",JLabel.CENTER);JLabel lbl6 = new JLabel("性别",JLabel.CENTER);JLabel lbl7 = new JLabel("专业",JLabel.CENTER);p1 = new JPanel (new FlowLayout());p1.add(lbl1);p1.add(tf1);p1.add(lbl2);p1.add(tf2);p2 = new JPanel (new GridLayout(2,1));p2.add(p1);p1.add(selBtn);p3 = new JPanel (new GridLayout(1,5));p3.add(lbl3);p3.add(lbl4);p3.add(lbl5);p3.add(lbl6);p3.add(lbl7);BorderLayout border = new BorderLayout();this.setLayout(border);this.add(p2,BorderLayout.NORTH);//完成语句⑹：当点击窗口的关闭按钮时只销毁该窗口，并不退出应用系统setSize(750,600);setLocation(150,50);setVisible(true);validate();}public void actionPerformed(ActionEvent e) {conn = DatabaseConnection.getConnection("jdbc:odbc:StudentDsn", "", "");try {String txt1,txt2,condition = "";txt1=tf1.getText();txt2=tf2.getText();if (txt1!=null && !txt1.equals(""))condition = " where sname like '%"+txt1+"%' ";if (txt2!=null && !txt2.equals(""))if (condition.equals(""))condition = " where major like '%"+txt2+"%' ";elsecondition =condition + " and major like '%"+txt2+"%' ";String sql = "select * from stu " + condition;stmt = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_READ_ONL Y); //完成语句⑺：提交sql语句，并将返回的记录集放在rs中//完成语句⑻：获取记录集中的记录条数，放在整形变量recordCount中GridLayout gl=new GridLayout(recordCount,1);if (resultPanel!=null){resultPanel.removeAll();//问题2：该语句的功能是什么？else{resultPanel = new JPanel(gl);//问题3：该条语句什么时候执行？}//问题2：test变量的作用是什么？if(test==1){scroll = new JScrollPane(resultPanel);split = new JPanel(new BorderLayout());split.add(p3,BorderLayout.NORTH);split.add(scroll,BorderLayout.CENTER);this.add(split,BorderLayout.CENTER);test++;}p3_1 = new JPanel[recordCount];tf3_1 = new JTextField[recordCount];tf4_1 = new JTextField[recordCount];tf5_1 = new JTextField[recordCount];tf6_1 = new JTextField[recordCount];tf7_1 = new JTextField[recordCount];rs.beforeFirst();//问题4：该条语句可不可以用rs.first()代替？为什么？int i = 0;while(rs.next()){tf3_1[i] = new JTextField(rs.getString(1));tf4_1[i] = new JTextField(rs.getString(2));tf5_1[i] = new JTextField(rs.getString(3));tf6_1[i] = new JTextField((rs.getString(4).equals("M"))?"男":"女");tf7_1[i] = new JTextField(rs.getString(5));tf3_1[i].setHorizontalAlignment(JTextField.CENTER);tf4_1[i].setHorizontalAlignment(JTextField.CENTER);tf5_1[i].setHorizontalAlignment(JTextField.CENTER);tf6_1[i].setHorizontalAlignment(JTextField.CENTER);tf7_1[i].setHorizontalAlignment(JTextField.CENTER);tf3_1[i].setEditable(false);tf4_1[i].setEditable(false);tf5_1[i].setEditable(false);tf6_1[i].setEditable(false);tf7_1[i].setEditable(false);//完成语句⑼：为文本框们添加监听器p3_1[i] = new JPanel (new GridLayout(1,5));p3_1[i].add(tf3_1[i]);p3_1[i].add(tf4_1[i]);p3_1[i].add(tf5_1[i]);p3_1[i].add(tf6_1[i]);p3_1[i].add(tf7_1[i]);resultPanel.add(p3_1[i]);i++;resultPanel.repaint();//问题5：该条语句可不可以取消？为什么？this.validate();//问题6：该条语句可不可以取消？为什么？} catch (SQLException e1) {e1.printStackTrace();}finally{//完成语句⑽：关闭数据库操作时占用的各种资源}public void focusGained(FocusEvent e) {//完成语句⑾：当文本框获得焦点时，文本框为红色}public void focusLost(FocusEvent e) {//完成语句⑿：当文本框失去焦点时，文本框为白色}}④AddFrame.javapackage sms;import java.awt.Dimension;import java.awt.FlowLayout;import java.awt.Toolkit;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.sql.Connection;import java.sql.SQLException;import java.sql.Statement;import javax.swing.Box;import javax.swing.ButtonGroup;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JOptionPane;import javax.swing.JPanel;import javax.swing.JRadioButton;import javax.swing.JTextField;public class AddFrame extends JFrame implements ActionListener{private Connection conn;private Statement stmt;JLabel lbl1 = null;JLabel lbl2 = null;JLabel lbl3 = null;JLabel lbl4 = null;JLabel lbl5 = null;JTextField tf1 = null;JTextField tf2 = null;JTextField tf4 = null;JTextField tf5 = null;JRadioButton man = null;JRadioButton woman = null;ButtonGroup sex = null;JButton addBtn = null;JPanel p1 = null;Box baseBox,boxV1,boxV2,boxH1;public AddFrame(){super("添加学生信息");//定义组件：从上到下，从左到右lbl1 = new JLabel("学号：");lbl2 = new JLabel("姓名：");lbl3 = new JLabel("性别：");lbl4 = new JLabel("年龄：");lbl5 = new JLabel("专业：");tf1 = new JTextField(20);tf2 = new JTextField(20);tf4 = new JTextField(20);tf5 = new JTextField(20);man = new JRadioButton("男",true);woman = new JRadioButton("女");sex = new ButtonGroup();sex.add(man);sex.add(woman);addBtn=new JButton("添加");addBtn.addActionListener(this);boxV1 = Box.createVerticalBox();boxV1.add(lbl1);boxV1.add(Box.createVerticalStrut(8));boxV1.add(lbl2);boxV1.add(Box.createVerticalStrut(8));boxV1.add(lbl3);boxV1.add(Box.createVerticalStrut(8));boxV1.add(lbl4);boxV1.add(Box.createVerticalStrut(8));boxV1.add(lbl5);boxH1 = Box.createHorizontalBox();boxH1.add(man);boxH1.add(Box.createHorizontalStrut(10));boxH1.add(woman);boxV2 = Box.createVerticalBox();boxV2.add(tf1);boxV2.add(Box.createVerticalStrut(8));boxV2.add(tf2);boxV2.add(Box.createVerticalStrut(8));boxV2.add(boxH1);boxV2.add(Box.createVerticalStrut(8));boxV2.add(tf4);boxV2.add(Box.createVerticalStrut(8));boxV2.add(tf5);baseBox = Box.createHorizontalBox();baseBox.add(boxV1);baseBox.add(Box.createHorizontalStrut(10));baseBox.add(boxV2);p1 = new JPanel (new FlowLayout());p1.add(baseBox);p1.add(addBtn);this.add(p1);this.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);setSize(300,250);Toolkit tool = this.getToolkit();Dimension dim = tool.getScreenSize();this.setLocation(dim.width/3+50,dim.height/3+50);setVisible(true);validate();}public void actionPerformed(ActionEvent e) {//完成语句⒀：获取数据库连接try {String txt1,txt2,txt3,txt4,txt5,sql;txt1=tf1.getText().trim();txt2=tf2.getText().trim();if(man.isSelected())txt3="M";else txt3="F";txt4=tf4.getText().trim();txt5=tf5.getText().trim();sql = "insert into stu(sno,sname,age,sex,major) values (";if (txt1.length()<=10 && Util.isNotEmpty(txt1) && Util.isDigits(txt1)){sql = sql + "'"+txt1+"','";if (txt2.length()<=10 && Util.isNotEmpty(txt2)){sql = sql + txt2+"',";if (txt4.length()<=2 && Util.isNotEmpty(txt4) && Util.isDigits(txt4)){sql = sql + Integer.parseInt(txt4)+",'";sql = sql + txt3+"','";if(txt5.length()<=25 && Util.isNotEmpty(txt5))sql = sql + txt5+"'";else{JOptionPane.showMessageDialog(this, "专业输入有误：0<长度<=25!");return ;}}else{//完成语句⒁：弹出消息对话框，内容是：年龄输入有误：0<长度<=2且是数字字符!return ;}}else {JOptionPane.showMessageDialog(this, "姓名输入有误：0<长度<=10!");return ;}}else {JOptionPane.showMessageDialog(this, "学号输入有误：0<长度<=10且是数字字符!");return ;}sql = sql + ")";int cnt = 0;//完成语句⒂：创建提交sql语句的对象，并将sql语句的执行结果赋给整型变量cnt。