Shulou(Shulou.com)05/31 Report--

This article mainly introduces how to set up and apply the database connection pool in Tomcat, which has a certain reference value, and interested friends can refer to it. I hope you will gain a lot after reading this article.

Configuration: Tomcat5.5+JEE (jsdk1.5) + WINXP

Or simply talk about the file configuration:

1: modify% tomcat%/conf/server.xml in

Add the following after that.

two。 Modify% tomcat%/conf/context.xm; and add it later

3. Modify tomcat%/conf/web.xml

MySQL DB Connection Pool

Jdbc/DBPool

Javax.sql.DataSource

Container

Shareable

This configuration is almost enough. If you don't understand the details, you can see the article you posted last time.

4. Write a program to test. (write a WEB program)

Mine is a program written by Myeclipse. It's a bit inconvenient not to map from the computer here (I want to cry).

1: write a connection class:

DBPool.java

Package com.test

Import javax.naming.Context

Import javax.naming.InitialContext

Import javax.naming.NamingException

Import javax.sql.DataSource

Public class DBPool {

Private static DataSource pool

Static {

Context env = null

Try {

Env = (Context) new InitialContext () .lookup ("java:comp/env")

Pool = (DataSource) env.lookup ("jdbc/DBPool")

If (pool==null)

System.err.println ("'DBPool' is an unknown DataSource")

} catch (NamingException ne) {

Ne.printStackTrace ()

}

}

Public static DataSource getPool () {

Return pool

}

}

2: write a Servlet:

Some of them are used to connect to the database and display query results.

Mytest.java

Package com.test

Import java.io.IOException

Import java.io.PrintWriter

Import java.sql.*

Import javax.servlet.ServletException

Import javax.servlet.http.HttpServlet

Import javax.servlet.http.HttpServletRequest

Import javax.servlet.http.HttpServletResponse

Public class Mytest extends HttpServlet {

/ * *

* Constructor of the object.

, /

Public Mytest () {

Super ()

}

/ * *

* Destruction of the servlet.

, /

Public void destroy () {

Super.destroy (); / / Just puts "destroy" string in log

/ / Put your code here

}

/ * *

* The doGet method of the servlet.

*

* This method is called when a form has its tag value method equals to get.

*

* @ param request the request send by the client to the server

* @ param response the response send by the server to the client

* @ throws ServletException if an error occurred

* @ throws IOException if an error occurred

, /

Public void doGet (HttpServletRequest request, HttpServletResponse response)

Throws ServletException, IOException {

Response.setContentType ("text/html;charset=gb2312")

PrintWriter out = response.getWriter ()

String id= (String) request.getParameter ("id")

Connection con=null

Try {

Con=DBPool.getPool () .getConnection ()

Statement stmt=con.createStatement ()

ResultSet rst=stmt.executeQuery ("select * from userinf where userid='" + id+ "'")

If (rst.next ()) {

Out.println ("

ID number: "+ rst.getInt (" userid "))

Out.println ("

User name: "+ com.test.ASSICTOGBR2312.trans (rst.getString (" name ")

Out.println ("

Address: "+ rst.getString (" address "))

Out.println ("

Birthday "+ rst.getDate (" year "))

}

Else {

Out.println ("without this ID")

Stmt.close ()

}

}

Catch (Exception e) {

E.printStackTrace ()

}

Finally {/ / be sure to pay attention to the closure of the database here, otherwise

/ / think about it for yourself.

Try {

If (contextual null) {

Con.close ()

}

}

Catch (Exception e) {

E.printStackTrace ()

}

}

}

/ * *

* The doPost method of the servlet.

*

* This method is called when a form has its tag value method equals to post.

*

* @ param request the request send by the client to the server

* @ param response the response send by the server to the client

* @ throws ServletException if an error occurred

* @ throws IOException if an error occurred

, /

Public void doPost (HttpServletRequest request, HttpServletResponse response)

Throws ServletException, IOException {

DoGet (request,response)

}

/ * *

* Initialization of the servlet.

*

* @ throws ServletException if an error occure

, /

Public void init () throws ServletException {

/ / Put your code here

}

}

3: write a JSP page:

Myjsp.jsp

My JSP 'MyJsp.jsp' starting page

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