You can have a look at the EL (expression language) description here. Both your code are correct, but I prefer the second one, as comparing a boolean to true or false is redundant. For better readibility, you can also use the not operator: <c:if test=”${not theBooleanVariable}”>It’s false!</c:if>
I know it’s supposed to be on by default, but I run across pages now and again (or even the same page that changes behavior) where the EL processing doesn’t happen. Adding the following to the top of any such pages should resolve the issue: <%@ page isELIgnored=”false” %> I add it to every page … Read more
You can just use the Universal Expression Language itself. You need an implementation (but there are a few to choose from). After that, you need to implement three classes: ELResolver, FunctionMapper and VariableMapper. This blog post describes how to do it: Java: using EL outside J2EE.
You can just put \ in front to escape the EL expression: \${variable} Alternatively, you can XML-escape the $: ${variable}
Assuming you are using Facelets, here’s a relatively good solution: create functions.taglib.xml in your WEB-INF add a context param indicating the location: <context-param> <param-name>facelets.LIBRARIES</param-name> <param-value> /WEB-INF/functions.taglib.xml </param-value> </context-param> In the xml put the following: <?xml version=”1.0″ encoding=”UTF-8″?> <!DOCTYPE facelet-taglib PUBLIC “-//Sun Microsystems, Inc.//DTD Facelet Taglib 1.0//EN” “https://facelets.dev.java.net/source/browse/*checkout*/facelets/src/etc/facelet-taglib_1_0.dtd”> <facelet-taglib xmlns=”http://java.sun.com/JSF/Facelet”> <namespace>http://yournamespace.com/fnc</namespace> <function> <function-name>concat</function-name> <function-class>com.yourpackage.utils.Functions</function-class> <function-signature> java.lang.String … Read more
Use <f:convertDateTime>. You can nest this in any input and output component. Pattern rules are same as java.text.SimpleDateFormat. <h:outputText value=”#{someBean.dateField}” > <f:convertDateTime pattern=”dd.MM.yyyy HH:mm” /> </h:outputText>
Closest what you can get in JSF/Facelets is placing an <ui:debug /> somewhere in the view: <ui:debug /> Pressing CtrlShiftD should then show a popup window with debug information about the component tree and all available request parameters and request/view/flash/session/application scoped variables. It’s basically a representation of the content of all those maps. The hotkey … Read more
If you’re already on EL 3.0 (Java EE 7; WildFly, Tomcat 8, GlassFish 4, etc), then you could use the new += operator for this: <h:commandButton … action=”#{someController.doSomething(id += ‘SomeTableId’)}” /> If you’re however not on EL 3.0 yet, and the left hand is a genuine java.lang.String instance (and thus not e.g. java.lang.Long), then use … Read more
This “feature” was result of a bugfix in EL which was introduced as per Tomcat 6.0.16. As per chapter 1.18.3 of the EL specification, a value of number type which is null should be coerced to 0. Before Tomcat 6.0.16 this was “incorrectly” been coerced to an empty string. After all, an empty string was … Read more
This is because the pgTitle variable is set in page scope. Check it here(sorry I can’t get an official documentation for this). If you want to make this work, you have to set the variable in request scope at least. To set your variable in request scope, use the scope attribute on <c:set>: <c:set var=”pgTitle” … Read more