Use the database connection pool that comes with Tomcat 7

1. In the conf \ Catalina \ localhost directory under the tomcat installation directory, create a file with the alias you intend to give the web application: Name: alias. xml

My example is Gentoo. xml. Note that the name must be the same as the value in path.

<Context path="/gentoo" docBase="D:\workplace\TomcatJDBC\WebRoot" debug="0" privileged="true"><Resource name="jdbc/gentoo"      auth="Container"      type="javax.sql.DataSource"      factory="org.apache.tomcat.jdbc.pool.DataSourceFactory"      testWhileIdle="true"      testOnBorrow="true"      testOnReturn="false"      validationQuery="SELECT 1"      validationInterval="30000"      timeBetweenEvictionRunsMillis="30000"      maxActive="100"      minIdle="10"      maxWait="10000"      initialSize="10"      removeAbandonedTimeout="60"      removeAbandoned="true"      logAbandoned="true"      minEvictableIdleTimeMillis="30000"      jmxEnabled="true"      jdbcInterceptors="org.apache.tomcat.jdbc.pool.interceptor.ConnectionState;org.apache.tomcat.jdbc.pool.interceptor.StatementFinalizer"      username="root"      password="yang"      driverClassName="com.mysql.jdbc.Driver"      url="jdbc:mysql://localhost:3306/web"/></Context> 

2. Use:

Context initContext = new InitialContext();Context envContext  = (Context)initContext.lookup("java:/comp/env");DataSource ds = (DataSource)envContext.lookup("jdbc/gentoo");Connection conn = ds.getConnection();