100■■■▲配置Tomcat数据库连接池▲■■■

Question

如果你的英文好的话,可以看看tomcat自己的说明,本身就有啊,你去找一下,在它的welcome.jsp里就有.数据库连接池DBCP对吧?我就是看的那个,还有就是,所谓的数据库连接池,是相当于水池子的作用吧,你要连接的是两个数据库,虽然密码一样但是它(DBCP)只能在一个库下起作效果,你的jdbc如果同时连接两个库的话,好像DBCP作用不是很大吧?

Answer 1

到SERVER。XML-》CONNECTOR配置一下，

Answer 2

在server.xml和web.xml中配置,一下是我的配置:
在server.xml中的host元素中加入:
<Context path="/DBTest" docBase="DBTest"
        debug="5" reloadable="true" crossContext="true">  <Logger className="org.apache.catalina.logger.FileLogger"
             prefix="localhost_DBTest_log." suffix=".txt"
             timestamp="true"/>  <Resource name="jdbc/TestDB"
               auth="Container"
               type="javax.sql.DataSource"/>  <ResourceParams name="jdbc/TestDB">
    <parameter>
      <name>factory</name>
      <value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
    </parameter>    <!-- Maximum number of dB connections in pool. Make sure you
         configure your mysqld max_connections large enough to handle
         all of your db connections. Set to 0 for no limit.
         -->
    <parameter>
      <name>maxActive</name>
      <value>100</value>
    </parameter>    <!-- Maximum number of idle dB connections to retain in pool.
         Set to 0 for no limit.
         -->
    <parameter>
      <name>maxIdle</name>
      <value>30</value>
    </parameter>    <!-- Maximum time to wait for a dB connection to become available
         in ms, in this example 10 seconds. An Exception is thrown if
         this timeout is exceeded.  Set to -1 to wait indefinitely.
         -->
    <parameter>
      <name>maxWait</name>
      <value>10000</value>
    </parameter>    <!-- MySQL dB username and password for dB connections  -->
    <parameter>
     <name>username</name>
     <value>sa</value>
    </parameter>
    <parameter>
     <name>password</name>
     <value>12388321</value>
    </parameter>    <!-- Class name for the old mm.mysql JDBC driver - uncomment this entry and comment next
         if you want to use this driver - we recommend using Connector/J though
    <parameter>
       <name>driverClassName</name>
       <value>org.gjt.mm.mysql.Driver</value>
    </parameter>
     -->
    
    <!-- Class name for the official MySQL Connector/J driver -->
    <parameter>
       <name>driverClassName</name>
       <value>com.microsoft.jdbc.sqlserver.SQLServerDriver</value>
    </parameter>
    
    <!-- The JDBC connection url for connecting to your MySQL dB.
         The autoReconnect=true argument to the url makes sure that the
         mm.mysql JDBC Driver will automatically reconnect if mysqld closed the
         connection.  mysqld by default closes idle connections after 8 hours.
         -->
    <parameter>
      <name>url</name>
      <value>jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=mywebdata1</value>
    </parameter>
  </ResourceParams>
</Context>
在web.xml中加入:
<resource-ref>
      <description>DB Connection</description>
      <res-ref-name>jdbc/TestDB</res-ref-name>
      <res-type>javax.sql.DataSource</res-type>
      <res-auth>Container</res-auth>
</resouce-ref>
你照着这个配吧

Answer 3

为什么不行呢？error:Cannot create JDBC driver of class '' for connect URL 'null'

Answer 4

测试代码：
<%@ page  contentType="text/html;charset=GBK" %>
<%@ page import="java.sql.*"%>
<%@ page import="javax.sql.*"%>
<%@ page import="javax.naming.*"%><% 
 
   try
  {
   Context initContext = new InitialContext();
Context envContext  = (Context)initContext.lookup("java:/comp/env");
DataSource ds = (DataSource)envContext.lookup("jdbc/sessiontestDB");
Connection conn = ds.getConnection();   Statement stmt = conn.createStatement();
   String strSql = " select * from WEB_USER_DETAIL";
   ResultSet rs = stmt.executeQuery(strSql);
   while(rs.next())
     {
      out.print("dd");                 
     }
   }
   catch(Exception ex)
  {
     out.print("error:"+ex.getMessage());
   ex.printStackTrace();
   }
%>
//---------------------------------------------------
<?xml version="1.0" encoding="ISO-8859-1"?><!DOCTYPE web-app
    PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
    "http://java.sun.com/dtd/web-app_2_3.dtd"><web-app>
  <display-name>Welcome to Tomcat</display-name>
  <description>
     Welcome to Tomcat
  </description>
<!-- JSPC servlet mappings start -->    <servlet>
        <servlet-name>org.apache.jsp.index_jsp</servlet-name>
        <servlet-class>org.apache.jsp.index_jsp</servlet-class>
    </servlet>    <servlet-mapping>
        <servlet-name>org.apache.jsp.index_jsp</servlet-name>
        <url-pattern>/index.jsp</url-pattern>
    </servlet-mapping>
<resource-ref>
<description>DB Connection</description>
<res-ref-name>jdbc/sessiontestDB</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
<!-- JSPC servlet mappings end --></web-app>
//-------------------------------------------------------
<?xml version='1.0' encoding='utf-8'?>
<Server>
  <Listener className="org.apache.catalina.mbeans.ServerLifecycleListener"/>
  <Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener"/>
  <GlobalNamingResources>
    <Environment name="simpleValue" type="java.lang.Integer" value="30"/>
    <Resource auth="Container" description="User database that can be updated and saved" name="UserDatabase" type="org.apache.catalina.UserDatabase"/>
    <Resource name="sessiontestDB" type="javax.sql.DataSource"/>
    <ResourceParams name="UserDatabase">
      <parameter>
        <name>factory</name>
        <value>org.apache.catalina.users.MemoryUserDatabaseFactory</value>
      </parameter>
      <parameter>
        <name>pathname</name>
        <value>conf/tomcat-users.xml</value>
      </parameter>
    </ResourceParams>
    <ResourceParams name="sessiontestDB">
      <parameter>
        <name>maxWait</name>
        <value>5000</value>
      </parameter>
      <parameter>
        <name>maxActive</name>
        <value>4</value>
      </parameter>
      <parameter>
        <name>password</name>
        <value>1234</value>
      </parameter>
      <parameter>
        <name>url</name>
        <value>jdbc:microsoft:sqlserver://localhost:9433;DatabaseName=TESTDATA</value>
      </parameter>
      <parameter>
        <name>driverClassName</name>
        <value>com.microsoft.jdbc.sqlserver.SQLServerDriver</value>
      </parameter>
      <parameter>
        <name>maxIdle</name>
        <value>2</value>
      </parameter>
      <parameter>
        <name>username</name>
        <value>sa</value>
      </parameter>
    </ResourceParams>
  </GlobalNamingResources>
  <Service name="Catalina">
    <Connector acceptCount="100" connectionTimeout="20000" disableUploadTimeout="true" port="80" redirectPort="8443">
    </Connector>
    <Connector port="8009" protocol="AJP/1.3" protocolHandlerClassName="org.apache.jk.server.JkCoyoteHandler" redirectPort="8443">
    </Connector>
    <Engine defaultHost="localhost" name="Catalina">
      <Host appBase="webapps" name="localhost">
        <Logger className="org.apache.catalina.logger.FileLogger" prefix="localhost_log." suffix=".txt" timestamp="true"/>
      </Host>
      <Logger className="org.apache.catalina.logger.FileLogger" prefix="catalina_log." suffix=".txt" timestamp="true"/>
      <Realm className="org.apache.catalina.realm.UserDatabaseRealm"/>
    </Engine>
  </Service>
</Server>