@Test
public void testIsWriteOperation() {

    PrincipalAuthority serviceAuthority = new PrincipalAuthority();
    assertTrue(serviceAuthority.isWriteOperation("PUT"));
    assertTrue(serviceAuthority.isWriteOperation("put"));
    assertTrue(serviceAuthority.isWriteOperation("Post"));
    assertTrue(serviceAuthority.isWriteOperation("POST"));
    assertTrue(serviceAuthority.isWriteOperation("DeLete"));
    assertTrue(serviceAuthority.isWriteOperation("DELETE"));
    assertFalse(serviceAuthority.isWriteOperation("GET"));
    assertFalse(serviceAuthority.isWriteOperation("Get"));
    assertFalse(serviceAuthority.isWriteOperation("HEAD"));
    assertFalse(serviceAuthority.isWriteOperation(null));
    assertFalse(serviceAuthority.isWriteOperation("Unknown"));
    assertFalse(serviceAuthority.isWriteOperation(""));
}