@Test
public void testIsSignedBy() throws Exception
{

    PGPPublicKey applePublicKey = PGPTestDataFactory.getPublicKey( "apple" );
    PGPPublicKey alicePublicKey = PGPTestDataFactory.getPublicKey( "alice" );
    assertTrue( PGPSignatureUtil.isSignedBy( applePublicKey, alicePublicKey ) );
    PGPPublicKey bobbyPublicKey = PGPTestDataFactory.getPublicKey( "bobby" );
    assertFalse( PGPSignatureUtil.isSignedBy( applePublicKey, bobbyPublicKey ) );
}