javax.el.ELException: Failed to parse the expression [{pz:instanceof(object,'com.project.domain.MyClass')}]

Question

Currenty I have a web project with JSF 1.2 and Facelets running in tomcat 6.0.18.0. I decided to upgrade the servlet container, thus i deployed in tomcat 7 and all seemed ok

Answer 1

You can also try changing the syntax. I had the same exact problem with code that I was maintaining when we were moving from Tomcat 6 to 7. I had to change myobject.class.name to myobject['class'].name. After I made this change my code worked perfectly again.

Answer 2

Add this line in catalina.properties ([tomcat folder]/conf), and it should fix the issue.

org.apache.el.parser.SKIP_IDENTIFIER_CHECK=true

However, you should not use the reserved words.

Answer 3

Great hint, indeed! I had to change in my jspx ${instance.class.simpleName == ...} with ${instance['class'].simpleName eq ...}.

I was moving from vFabric on tomcat 6 to vFabric on tomcat 7

Answer 4

This is actually a misleading exception. It has a different underlying cause. The function name instanceof is invalid.

The EL 2.2 specification says the following:

1.14 Reserved Words

The following words are reserved for the language and must not be used as identifiers.

    and   eq     gt     true   instanceof
    or    ne     le     false  empty
    not   lt     ge     null   div        mod

Note that many of these words are not in the language now, but they may be in the future, so developers must avoid using these words.

and

1.19 Collected Syntax

...

Identifier ::= Java language identifier

...

Where the Java language identifier stands for keywords like instanceof, if, while, class, return, static, new, etc. They may not be used as variable/function names in EL. In case you have properties with those names, use the brace notation instead like so #{bean['class'].simpleName} instead of #{bean.class.simpleName}.

This was been fixed in Tomcat 7.0.4 or somewhere near before this version as indicated by issue 50147 wherein someone else pointed out the same problem as you have. So, to solve your problem, you have to rename your EL function name to for example isInstanceOf or something.