在tomcat中配置mysql数据库连接池的方法及第三方对数据库的封装：dbutils

你可在每个web工程目录下的META-INF\context.xml文件中.

context.xml文件中的内容可以这样写:
<Context>

<Resource  name="jdbc/mysqlds"
 auth="Container"
 type="javax.sql.DataSource" 
 maxActive="100" 
 maxIdle="100"
 maxWait="5000"  
 username="root"  
 password="root"
 driverClassName="com.mysql.jdbc.Driver" 
 url="jdbc:mysql://127.0.0.1/liuwei"
 />

 

</Context>

 

 package cn.com.jobedu.blog;

import java.io.IOException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import javax.naming.InitialContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.sql.DataSource;

public class BlogServlet extends HttpServlet {
 private static final long serialVersionUID = 1L;

 public void doGet(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
  doPost(request, response);
 }

 public void doPost(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
  request.setCharacterEncoding("UTF-8");
  System.out.println("dopost");
  String title = request.getParameter("title");
  String content = request.getParameter("content");
  String categoryId = request.getParameter("category");
  DataSource ds = null;
  try {
   // 通过在context.xml文件，设定的数据源对象的名字，获取数据源对象
   InitialContext context = new InitialContext();
   ds = (DataSource) context.lookup("java:/comp/env/jdbc/mysqlds");
  } catch (Exception e) {
   System.out.println("获取数据源时出错");
  }
  int result = 0;
  try {
   Connection conn = ds.getConnection();
   String sql = "insert into blog (title, content,category_id,createdtime) values (?, ?, ?, now())";
   PreparedStatement pstmt = conn.prepareStatement(sql);
   pstmt.setString(1, title);
   pstmt.setString(2, content);
   pstmt.setInt(3, Integer.parseInt(categoryId));
   result = pstmt.executeUpdate();
   System.out.println(result);
  } catch (SQLException e) {
   e.printStackTrace();
  }
  String message = "";
  if (result == 1) {
   message = "添加博文成功";
  } else {
   message = "添加博文失败";
  }

  request.setAttribute("message", message);
  request.getRequestDispatcher("/addBlogResult.jsp").forward(request,
    response);
 }
}

 

 

第三方对数据库的封装：dbutils

package cn.com.jobedu.blog;

import java.io.IOException;
import java.sql.Connection;
import java.sql.SQLException;

import javax.naming.InitialContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.sql.DataSource;

import org.apache.commons.dbutils.QueryRunner;

public class BlogServlet extends HttpServlet {

 public void doGet(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
  doPost(request, response);

 }

 public void doPost(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {

  request.setCharacterEncoding("UTF-8");
  String title = request.getParameter("title");
  String content = request.getParameter("content");
  String categoryId = request.getParameter("category");

  System.out.println(title);
  System.out.println(content);
  System.out.println(categoryId);

  DataSource ds = null;
  try {
   // 通过在context.xml文件，设定的数据源对象的名字，获取数据源对象
   InitialContext context = new InitialContext();
   ds = (DataSource) context.lookup("java:/comp/env/jdbc/mysqlds");
  } catch (Exception e) {
   System.out.println("获取数据源时出错");
  }
  int result = 0;
  try {
   String sql = "insert into blog (title, content,category_id,createdtime) values (?, ?, ?, now())";
   QueryRunner qr = new QueryRunner(ds);
   String parmas[] = { title, content, categoryId };
   result = qr.update(sql, parmas);
   System.out.println(result);
  } catch (SQLException e) {
   e.printStackTrace();
  }
  String message = "";
  if (result == 1) {
   message = "添加博文成功";
  } else {
   message = "添加博文失败";
  }

  request.setAttribute("message", message);
  request.getRequestDispatcher("/addBlogResult.jsp").forward(request,
    response);
 }

}