<logger className="org.apache.catalina.logger.FileLogger"
            directory="logs"  prefix="localhost_log." suffix=".txt"
            timestamp="true"/>
         <context docBase="cmmi" path="/cmmi" 
                 reloadable="true" crossContext="true">
	    <logger className="org.apache.catalina.logger.FileLogger"
                     prefix="localhost_lovehome_log." 
                     suffix=".txt" timestamp="true"/>
       <resource name="jdbc/access" auth="Container" 
              type="javax.sql.DataSource"
              maxActive="100" maxIdle="30" maxWait="10000"
              driverClassName="sun.jdbc.odbc.JdbcOdbcDriver"
              username="sa" password="12345"
              url="jdbc:odbc:work"
              defaultAutoCommit="true" removeAbondoned="true"
              removeAbondonedTimeout="60" logAbondoned="true"/>
        </context>

package database;
import java.sql.*;
public class DBConnection{
	private Connection conn = null;
	private Statement stmt = null;
	ResultSet rs = null;
	public ResultSet executeQuery(String sql) {
	try {
	     conn =SqlTestDS.getConnection();
             stmt=conn.createStatement
(ResultSet.TYPE_SCROLL_INSENSITIVE,
ResultSet.CONCUR_READ_ONLY);
			rs = stmt.executeQuery(sql);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return rs;
	}
	public void executeUpdate(String sql) {
		try {
			conn = SqlTestDS.getConnection();
			stmt =conn.createStatement
(ResultSet.TYPE_SCROLL_INSENSITIVE,
ResultSet.CONCUR_READ_ONLY);
			stmt.executeUpdate(sql);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	public void closeStmt() {
		try {
			stmt.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	public void closeConn() {
		try {
			conn.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}

package database;
import javax.sql.DataSource;
import javax.naming.*;
import java.sql.*;
public class SqlTestDS {
private static DataSource ds = null;
static {
init();
}
private static void init() {
try {
// 1、创建命名服务环境
Context ctx = new InitialContext();
if (ctx == null)
throw new Exception("No Context");
 
// 2、从JNDI中查询数据源对象
ds = (DataSource) ctx.lookup("java:comp/env/jdbc/sqlserver");
 
} catch (Exception e) {
e.printStackTrace();
}
}
 
// 将构造函数定义为private权限是为了保证全局只有一个SqlTestDS实例
// 也就是实现了单例模式
private SqlTestDS() {
 
}
 
public static Connection getConnection() throws SQLException {
if (ds == null) {
throw new SQLException("数据源对象为空！");
} else {
// 3、从数据源中获取数据库连接
return ds.getConnection();
}
}
}

<context
       docBase="C:/eclipse/workspace/myweb/hello"
        path="/hello"
         reloadable="true"
<resource name="jdbc/mysql" auth="Container" type="javax.sql.DataSource"
	maxActive="100" maxIdle="30" maxWait="10000"
	driverClassName="com.mysql.jdbc.Driver"
	username="root" password="123456"
	url="jdbc:mysql://localhost/testmysql"
	defaultAutoCommit="true" removeAbondoned="true"
	removeAbondonedTimeout="60" logAbondoned="true"/>
</context>

	<resource-ref>
		<res-ref-name>jdb/mysql</res-ref-name>
		<res-type>javax.sql.DataSource</res-type>
		<res-auth>Container</res-auth>
	</resource-ref>