conndb.java

这是一个基于图书馆系统 主要是用struts hibernate oracle做的

package com.core;

import java.sql.*;

public class ConnDB {
    public Connection conn=null;
    public ResultSet rs=null;
    public Statement stmt=null;
    private String proxool = "com.mysql.jdbc.Driver";
    private String poolname = "jdbc:mysql://localhost:3306/db_library";
    private String username ="root";
    private String password = "root";
    //说明：此处需要配置web.xml文件
    public ConnDB() {   //构造方法
    }
    public Connection getConnection() {
      try {
          Class.forName(proxool);
          conn = DriverManager.getConnection(poolname,username,password);
      } catch (Exception e) {
          System.out.println(e.getMessage());
      }
      if (conn == null) {
          System.out.println("没有获取到数据库连接");
      }
      return conn;
    }
    /*
 *功能：执行查询语句
 */
public ResultSet executeQuery(String sql) {
  try {
    conn = getConnection();
    stmt = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
                                ResultSet.CONCUR_READ_ONLY);
    rs = stmt.executeQuery(sql);
  }
  catch (SQLException ex) {
    System.err.println(ex.getMessage());
  }
  return rs;
}

/*
 *功能:执行更新操作
 */
public int executeUpdate(String sql) {
  int result = 0;
  try {
    conn = getConnection();
    stmt = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
                                ResultSet.CONCUR_READ_ONLY);
    result = stmt.executeUpdate(sql);
  }
  catch (SQLException ex) {
    result = 0;
  }
  try {
    stmt.close();
  }
  catch (SQLException ex1) {
  }
  return result;
}

    /*
     *功能:关闭数据库的连接
     */
    public void close() {
      try {
        if (rs != null) {
          rs.close();
        }
      }
      catch (Exception e) {
        e.printStackTrace(System.err);
      }
      try {
        if (stmt != null) {
          stmt.close();
        }
      }
      catch (Exception e) {
        e.printStackTrace(System.err);
      }
      try {
        if (conn != null) {
          conn.close();
        }
      }
      catch (Exception e) {
        e.printStackTrace(System.err);
      }
  }
}