BuildWrapper.tearDown() build result is null

[Max Spring]

I have a BuildWrapper.  The build parameter in its tearDown() method gives null 
as build result.

  public Environment setUp(AbstractBuild build, Launcher launcher, 
BuildListener listener) throws InterruptedException {
    return new Environment() {
      @Override
      public boolean tearDown(AbstractBuild build, BuildListener listener) 
throws IOException, InterruptedException {
        System.out.println("build.getResult() -> "+build.getResult());
        return true;
      }
    };
  }

I thought tearDown() gets called after the build finished, so it should have a 
result.

What's the right way to get a hold of a result, after a build finished?

Thanks!
-Max