连接数据库异常！急！！ Name newstest is not bound in this Context

异常javax.naming.NameNotFoundException: Name newstest is not bound in this Context
at org.apache.naming.NamingContext.lookup(NamingContext.java:770)
at org.apache.naming.NamingContext.lookup(NamingContext.java:140)
at org.apache.naming.NamingContext.lookup(NamingContext.java:781)
at org.apache.naming.NamingContext.lookup(NamingContext.java:140)
at org.apache.naming.NamingContext.lookup(NamingContext.java:781)
at org.apache.naming.NamingContext.lookup(NamingContext.java:153)
at org.apache.naming.SelectorContext.lookup(SelectorContext.java:152)
at javax.naming.InitialContext.lookup(Unknown Source)
at com.yourcompany.struts.DB.DButil.<init>(DButil.java:20)连接代码
public class DButil {
DataSource ds =null;
Connection conn = null;
// Statement stmt = null;public DButil()
{
try
{
InitialContext context = new InitialContext();
this.ds =(DataSource)context.lookup("java:comp/env/newstest");
System.out.print("test");
conn = ds.getConnection();
}
catch(Exception e)
{
e.printStackTrace();
}
}
}tomcat server。xml 配置
<Context path="" docBase="E:\test\WebRoot"
reloadable="true" crossContext="true"><Resource name="jdbc/mssqlds" 
auth="Container" 
type="javax.sql.DataSource"
maxActive="100" maxIdle="30" maxWait="10000"
username="sa" password="yeye" 
driverClassName="net.sourceforge.jtds.jdbc.Driver"
url="jdbc:jtds:sqlserver://localhost:1433/newstest"/>
</Context>