Home | History | Annotate | Download | only in cts 
      1 /*
      2  * Copyright (C) 2008 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package android.database.cts;
     18 
     19 import android.database.Observable;
     20 import android.test.AndroidTestCase;
     21 
     22 public class ObservableTest extends AndroidTestCase {
     23     public void testRegisterUnRegisterObserver() {
     24         MockObservable observable = new MockObservable();
     25 
     26         // Test register a null observer object
     27         try {
     28             observable.registerObserver((null));
     29             fail("registerObserver should throw a IllegalArgumentException here.");
     30         } catch (IllegalArgumentException e) {
     31         }
     32 
     33         Object observer = new Object();
     34         // In the beginning, Observable has no observer object, nothing to be unregistered.
     35         try {
     36             observable.unregisterObserver(observer);
     37             fail("unregisterObserver should throw a IllegalStateException here.");
     38         } catch (IllegalStateException e) {
     39         }
     40 
     41         // Test unregister a null object, the Observable will unregister nothing.
     42         try {
     43             observable.unregisterObserver(null);
     44             fail("unregisterObserver should throw a IllegalArgumentException here.");
     45         } catch (IllegalArgumentException e) {
     46         }
     47 
     48         // Test register a observer object
     49         observable.registerObserver(observer);
     50         // If previous registerObserver was executed successfully, the object can't be registered
     51         // twice.
     52         try {
     53             observable.registerObserver(observer);
     54             fail("registerObserver should throw a IllegalStateException here.");
     55         } catch (IllegalStateException e) {
     56         }
     57 
     58         // Test unregister a observer object
     59         observable.unregisterObserver(observer);
     60         // If unregister function was executed successfully, the input observer object will be
     61         // removed, so it can not be unregistered anymore, and it can be registered again.
     62         try {
     63             observable.unregisterObserver(observer);
     64             fail("unregisterObserver should throw a IllegalStateException here.");
     65         } catch (IllegalStateException e) {
     66         }
     67         observable.registerObserver(observer);
     68     }
     69 
     70     public void testUnregisterAll() {
     71         MockObservable observable = new MockObservable();
     72         Object observer1 = new Object();
     73         Object observer2 = new Object();
     74 
     75         observable.registerObserver(observer1);
     76         observable.registerObserver(observer2);
     77 
     78         // If a observer was registered, it can't be registered again.
     79         try {
     80             observable.registerObserver(observer1);
     81             fail("registerObserver should throw a IllegalStateException here.");
     82         } catch (IllegalStateException e) {
     83         }
     84         try {
     85             observable.registerObserver(observer2);
     86             fail("registerObserver should throw a IllegalStateException here.");
     87         } catch (IllegalStateException e) {
     88         }
     89 
     90         // unregisterAll will unregister all the registered observers.
     91         observable.unregisterAll();
     92         // The Observable will be empty after unregisterAll, so it can register observers again.
     93         observable.registerObserver(observer1);
     94         observable.registerObserver(observer2);
     95     }
     96 
     97     private class MockObservable extends Observable<Object> {
     98     }
     99 }
    100