Do tags written in Java (i.e., extending BodyTagSupport or TagSupport) perform better than .tag files?

Question

At work some developers are changing .tag files into tags that are written in Java. The reason was performance. They stated that there was a ten-fold increase in performance when comparing .tag files and those written in Java. The evidence was empirical.

I'm trying to find some factual data to back this up, but couldn't find any performance comparisons online. I did find documentation that talked about tag pooling and how that can improve performance, but I couldn't find anything comparing the two.

Answer 1

the .tag files are supposed to be compiled to java code on first access. So you might have a performance hit just on the first access, afterwards it's supposed to be the same.

You can avoid that by pre-compiling them. The way to setup the pre-compilation varies between servers (see this question for example)

Answer 2

Theoretically speaking, JSP tags (.tag) might cause a performance hit initially, but once executed it should work as fast as a Java based custom tag. Because, JSP tags (.tag) works similar to JSPs.