Removing lines from a string containing certain character

I am working a Java project to read a java class and extract all DOC comments into an HTML file. I am having trouble cleaning a string of the lines I don't need.

Lets say I have a string such as:

"/**
* Bla bla
*bla bla
*bla bla
*/

CODE
CODE
CODE

/**
* Bla bla
*bla bla
*bla bla
*/ "

I want to remove all the lines not starting with *.

Is there any way I can do that?