Question

I am working on segment of code which needs to be able to recognize no-args constructor declarations in Java source files. While these declarations need to be syntactically correct, they may still be spread across several lines, for example:

public MyCons()

or

public
   MyCons()  

or even

public

   MyCons
  (

    )    

I am very new to regexp in Java, so I am not sure how to get this working. What I have tried so far is this:

public[\\s|\\n]*MyCons[\\s|\\n]*\\(\\S+\\)

It does not seem to detect cases involving multiple alternating whitespaces and newlines though, as in the last example above. Also, it would be great if I could replace MyCons with a regular expression accepting just a word (although this is not strictly necessary).

How could I solve this?

Answer 1

You need to use backreference since class name and constructor name is always same..

class\\s*([a-zA-Z\\d$]+).*?(public\\s+\\1\\s*\\(\\s*\\))

Group 2 captures the required constructor

You need to use DOTALL regex option while matching