Suppress Java findbugs errors (ei_expose_rep)

I have a Java gettor method, as follows:

import java.util.Date;
//...
public Date getSomeDate() {
  return someDate;
}

And findbugs report that this exposes a mutable object: "the internal representation can be exposed by returning a reference to the mutable object." I changed the code to:

import java.util.Date;
//...
public Date getSomeDate() {
  return new Date(someDate.getTime());
}

But findbug still reports the same vulnerability What else can I do to suppress / solve this problem? I run findbugs 1.3 in the intellj 10 findbugs plug-in nine

Solution

I just realized that findbugs analyzed the compiled code (. Class file), not the source code After rebuilding and rerunning findbugs, the problem disappears