数据库操作类

数据库操作类

 

import java.util.*;
import java.sql.*;

/**
* <p>Title: homework guestbook</p>
* @author ai829
*/

public class conn_bean {
// public static void main(String args[]) { 测试连接
private Connection conn;
Vector vector;
public conn_bean() {
String dbs = "";
try {
//注册
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
//连接
conn = DriverManager.getConnection("jdbc:odbc:book",
"ai829", "ai829");
/*if (conn != null) {
System.out.println("数据库连接成功！");
}else {
System.out.println("数据库连接失败！");
}*/

}
catch (Exception ex) {
ex.printStackTrace();
}
}

public String insert(String sql) { //插入数据
boolean flag = false;
String text = "";
try {
if (conn != null) {
Statement stat = conn.createStatement();
flag = stat.execute(sql);
stat.close();
}
}
catch (SQLException ex) {
}
if (flag) {
text = "插入成功！";
}
else {
text = "插入失败！";
}
return text;
}

public String update(String sql) { //修改数据
boolean flag = false;
String text = "";
try {
if (conn != null) {
Statement stat = conn.createStatement();
flag = stat.execute(sql);
stat.close();
}
}
catch (Exception ex) {
}
if (flag) {
text = "修改成功！";
}
else {
text = "修改失败！";
}
return text;
}

public String delete(String sql) { //删除数据
boolean flag = false;
String text = "";
try {
if (conn != null) {
Statement stat = conn.createStatement();
flag = stat.execute(sql);
stat.close();
}
}
catch (Exception ex) {
}
if (flag) {
text = "删除成功！";
}
else {
text = "删除失败！";
}
return text;
}

public Vector select(String sql) { //查询数据
boolean flag = false;
ResultSet rs = null;
try {
if (conn != null) {
Statement stat = conn.createStatement();
rs = stat.executeQuery(sql);
Vector rec_vector = new Vector();
while (rs.next()) {
rec_vector.addElement(String.valueOf(rs.getInt("学号")));
rec_vector.addElement(rs.getString("姓名"));
rec_vector.addElement(String.valueOf(rs.getInt("年龄")));
rec_vector.addElement(rs.getString("性别"));
rec_vector.addElement(rs.getString("系名"));
vector.addElement(rec_vector);
}

stat.close();
}
}
catch (Exception ex) {
}
return vector;
}

public void close() { //关闭数据
try {
conn.close();
}
catch (Exception ex) {
}
}

}