有关taglib的问题
<%@ taglib uri="/WEB-INF/struts-logic.tld" prefix="logic" %>
<%@ taglib uri="/WEB-INF/struts-template.tld" prefix="template" %>
<%@ taglib uri="/WEB-INF/struts-bean.tld" prefix="bean" %>
<%@ taglib uri="/WEB-INF/struts-html.tld" prefix="html" %>
<%@ page import="com.borland.internetbeans.*,com.borland.dx.dataset.*,com.borland.dx.sql.dataset.*" %>
<%@ taglib uri="/internetbeans.tld" prefix="ix" %>
..........
<logic:equal value="true" name="sessionBean" property="isLoggedIn">
<logic:notEqual value="0" name="sessionBean" property="rowCount">
<html:form action="purchaseAction" method="post">
<html:submit value="Check Out" property=""/>
</html:form>
</logic:notEqual>
</logic:equal>
请帮忙解读一下........之后的部分.
并请说明:容器是如何知道去执行哪一个类的程式的.