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;

importjava.sql.Connection;

importjava.sql.PreparedStatement;

importjava.sql.SQLException;

importjavax.naming.InitialContext;

importjavax.servlet.ServletException;

importjavax.servlet.http.HttpServlet;

importjavax.servlet.http.HttpServletRequest;

importjavax.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)

throwsServletException,IOException{

doPost(request,response);

 }

 public void doPost(HttpServletRequest request, HttpServletResponse response)

throwsServletException,IOException{

request.setCharacterEncoding("UTF-8");

System.out.println("dopost");

Stringtitle=request.getParameter("title");

Stringcontent=request.getParameter("content");

StringcategoryId=request.getParameter("category");

DataSourceds=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

InitialContextcontext=newInitialContext();

ds=(DataSource)context.lookup("java:/comp/env/jdbc/mysqlds");

}catch(Exceptione){

System.out.println("获取数据源时出错");

}

intresult=0;

try{

Connectionconn=ds.getConnection();

Stringsql="insertintoblog(title,content,category_id,createdtime)values(?,?,?,now())";

PreparedStatementpstmt=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(SQLExceptione){

e.printStackTrace();

}

Stringmessage="";

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;

importjava.sql.Connection;

import java.sql.SQLException;

import javax.naming.InitialContext;

importjavax.servlet.ServletException;

importjavax.servlet.http.HttpServlet;

importjavax.servlet.http.HttpServletRequest;

importjavax.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)

throwsServletException,IOException{

  doPost(request, response);

 }

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

  request.setCharacterEncoding("UTF-8");

Stringtitle=request.getParameter("title");

Stringcontent=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

InitialContextcontext=newInitialContext();

ds=(DataSource)context.lookup("java:/comp/env/jdbc/mysqlds");

}catch(Exceptione){

System.out.println("获取数据源时出错");

}

intresult=0;

try{

Stringsql="insertintoblog(title,content,category_id,createdtime)values(?,?,?,now())";

QueryRunnerqr=newQueryRunner(ds);

Stringparmas[]={title,content,categoryId};

result=qr.update(sql,parmas);

System.out.println(result);

}catch(SQLExceptione){

e.printStackTrace();

}

Stringmessage="";

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);

 }

}