How to configure syntax highlighting for a custom language in vim

The required lines are as follows:

" Include PHP highlighting between **phpbegin** and **phpend** tags
syn include @notesPHP syntax/php.vim
syn region phpCustom start=+\*\*phpbegin\*\*+ keepend end=+\*\*phpend\*\*+ contains=@notesPHP

" Include JavaScript highlighting between **jsbegin** and **jsend** tags
syn include @notesJavaScript syntax/javascript.vim
syn region javaScriptCustom start=+\*\*jsbegin\*\*+ keepend end=+\*\*jsend\*\*+me=s-1 contains=@nJavaScript

Have a look at the cSyntaxAfter plugin. It highlights operators et cetera.

Another option is to edit the syntax/java.vim script and add highlighting for the Operator group. Have a look at syntax/pascal.vim as an example.

It you want to use italics for class names, that should be possible if the java syntax file recognizes them as a group, and I think it does. It seems that class names are in the JavaTypedef group.

You would then have to define a new highlight for that group. That would mean removing the line

JavaHiLink javaTypedef                Typedef

from the syntax file, and adding a new one. Below I'm re-using the hightlight declaration for Type, which is what Typedef is linked to. I changed the term from underline to italic.

You should put the following in yout java.vim syntax file.

hi javaTypedef term=italic cterm=NONE ctermfg=LightGreen ctermbg=NONE gui=bold guifg=#60ff60 guibg=NONE