1 /*
2  * Copyright (C) 2010 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 package com.android.contacts.vcard;
17 
18 import java.util.concurrent.ExecutorService;
19 import java.util.concurrent.Future;
20 import java.util.concurrent.RunnableFuture;
21 import java.util.concurrent.TimeUnit;
22 
23 /**
24  * A base processor class. One instance processes vCard one import/export request (imports a given
25  * vCard or exports a vCard). Expected to be used with {@link ExecutorService}.
26  *
27  * This instance starts itself with {@link #run()} method, and can be cancelled with
28  * {@link #cancel(boolean)}. Users can check the processor's status using {@link #isCancelled()}
29  * and {@link #isDone()} asynchronously.
30  *
31  * {@link #get()} and {@link #get(long, TimeUnit)}, which are form {@link Future}, aren't
32  * supported and {@link UnsupportedOperationException} will be just thrown when they are called.
33  */
34 public abstract class ProcessorBase implements RunnableFuture<Object> {
35 
36     /**
37      * @return the type of the processor. Must be {@link VCardService#TYPE_IMPORT} or
38      * {@link VCardService#TYPE_EXPORT}.
39      */
getType()40     public abstract int getType();
41 
42     @Override
run()43     public abstract void run();
44 
45     /**
46      * Cancels this operation.
47      *
48      * @param mayInterruptIfRunning ignored. When this method is called, the instance
49      * stops processing and finish itself even if the thread is running.
50      *
51      * @see Future#cancel(boolean)
52      */
53     @Override
cancel(boolean mayInterruptIfRunning)54     public abstract boolean cancel(boolean mayInterruptIfRunning);
55     @Override
isCancelled()56     public abstract boolean isCancelled();
57     @Override
isDone()58     public abstract boolean isDone();
59 
60     /**
61      * Just throws {@link UnsupportedOperationException}.
62      */
63     @Override
get()64     public final Object get() {
65         throw new UnsupportedOperationException();
66     }
67 
68     /**
69      * Just throws {@link UnsupportedOperationException}.
70      */
71     @Override
get(long timeout, TimeUnit unit)72     public final Object get(long timeout, TimeUnit unit) {
73         throw new UnsupportedOperationException();
74     }
75 }
76