JBoss 连接数池错误（急救）

错误信息：

javax.naming.NoInitialContextException: Need to specify class name in environment or system property, or as an applet parameter, or in an application resource file:  java.naming.factory.initial


Jboss-ds.xml

<?xml version="1.0" encoding="UTF-8"?>

<datasources>
  <local-tx-datasource>
    <jndi-name>MySqlDS</jndi-name>
    <connection-url>jdbc:mysql://localhost:3306/bookshop</connection-url>
    <driver-class>com.mysql.jdbc.Driver</driver-class>
    <user-name>root</user-name>
    <password>root</password>
    <!--
    <exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.MySQLExceptionSorter</exception-sorter-class-name>
    <metadata>
       <type-mapping>mySQL</type-mapping>
    </metadata>
    -->
  </local-tx-datasource>
</datasources>



java源代码：

         InitialContext myInitialContext = new InitialContext();
        Context myEnvironment=(Context)myInitialContext.lookup("java:comp/env");
        String myDataSourceName = (String) myEnvironment.lookup("MySqlDS");
        DataSource myDataSource = (DataSource) myInitialContext.lookup( myDataSourceName);
        Connection conn=myDataSource.getConnection();
        if(conn!=null){
            System.out.println("连接成功");
        }
        else{
            System.out.println("连接失败");
        }