JAVA的连接池技术

 

     //1.先配置Tomcat下的server.xml(我的Tomcat的版本是5.0.28)

     //打开server.xml,在<Host>标记内加入下面的代码

     <Context   path="/LianJieChi"  docBase="LianJieChi">              <!--项目名及项目所在的路径 -->
   <Resource                                                                             <!-- 配置数据源-->
      auth="container"
      name="link"
      type="javax.sql.DataSource"
   />
   <ResourceParams name="link">                                               <!--数据源的详细信息 -->
    <parameter>
     <name>factory</name>  
     <value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
    </parameter>
    <parameter>
     <name>maxActive</name>                                                  <!--最大连接个数 -->
     <value>100</value>                                                            <!--我设置的是100 -->
    </parameter>
    <parameter>
     <name>maxIdle</name>                                                       <!--最大守候连接个数 -->
     <value>30</value>                                                               <!--我设置的是30 -->
    </parameter>
    <parameter>
     <name>maxWait</name>                                                       <!--用户等待的时间 -->
     <value>5000</value>                                                             <!--以毫秒为单位,这里设置的是5秒 -->
    </parameter>
    <parameter>
     <name>username</name>                                                       
     <value>数据库用户名</value>
    </parameter>
    <parameter>
     <name>password</name>
     <value>数据库用户密码</value>
    </parameter>
    <parameter>
     <name>driverClassName</name>                                            <!--数据库驱动名字 -->
     <value>com.microsoft.jdbc.sqlserver.SQLServerDriver</value>
    </parameter>
    <parameter>
     <name>url</name>                                                                <!--数据库链接url -->
     <value>jdbc:microsoft:sqlserver://地址:端口号;DatabaseName=库名</value>
    </parameter>
   </ResourceParams>

</Context>

     //2.将jar包导入Tomcat下的common/lib

     //3.在项目中建连库类

          import java.sql.Connection;
          import java.sql.SQLException;

          import javax.naming.Context;
          import javax.naming.InitialContext;
          import javax.naming.NamingException;
          import javax.sql.DataSource;

          public class DBLink {
                Connection con = null;
                public Connection getCon() throws NamingException, SQLException
                {

                      //初始化上下文
                      Context con1 = new InitialContext();

                      //获得数据源
                      DataSource ds = (DataSource)con1.lookup("java:comp/env/link");          //java:comp/env/数据源名(Tomcat下配置的源的name)

                      //获得连接
                      con = ds.getConnection();
                      return con;
               }

               //关闭Connection的方法
                public void Close(Connection con)
                {
                      try {
                                 con.close();
                           } catch (SQLException e) {
                                 e.printStackTrace();
                           }
                }

          }