resource-env-ref vs. resource-ref

DD Elemente, die Referenzen auf Resourcen oder EJB Resourcen darstellen sind: <ejb-ref>: Erzeugt einen Alias für eine Bean <resource-ref>: Referenz zu Resource Manager, geliefert werden funktionierende Connections,  z.B. javax.sql.DataSource <resource-env-ref>: Referenz zu Umgebungs-Informationen, mit deren Hilfe Connections erzeugt werden können: z.B. JMS The way I think of it, for the purposes of the OCWCD exam is:…

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Expression Language – Implicit object

JSTL Implicit Objects   Implicit Object Type Key Value cookie Map Cookie name Cookie header Map Request header name Request header value headerValues Map Request header name String[] of request header values initParam Map Initialization parameter name Initialization parameter value param Map Request parameter name Request parameter value paramValues Map Request parameter name String[] of…

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Servlet 3.0 Security Annotations

The following is the update on Servlet 3.0 security annotations: As in servlet 2.5, @DenyAll, @PermitAll, @RolesAllowed will not apply to servlets. @TransportProtected will not be added to JSR 250. The following new annotations will be added to javax.servlet.annotation: ServletSecurity HttpConstraint HttpMethodConstraint Note that @ServletSecurity is a type level annotation and the rests are used…

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Java EE 6 Web Component Developer Certified Expert

TOPICS Introduction to Java Servlets Describe web applications, CGI, and the role of Java Describe benefits of Java servlet technology Create a simple Java Servlet Define three-tier architecture Define Model-View-Controller (MVC) architecture Introduction to Java Server Pages Describe why Servlets are not the whole solution Describe essentials of JSPs Understand the fundamentals and reasons for…

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Using JSTL

  The problem with EL and standards actions is that they have no flow control statements for example what if you wanted to loop through an array, in a scriptlet you would use a for loop but you are trying to get away from scripting, what you need is custom tags. They are as easy to…

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