FetchProfile.java revision 345c43e12db42f6bdc0c15ac1c96af10164a458c 
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
17package com.android.emailcommon.mail;
18
19import java.util.ArrayList;
20
21/**
22 * <pre>
23 * A FetchProfile is a list of items that should be downloaded in bulk for a set of messages.
24 * FetchProfile can contain the following objects:
25 *      FetchProfile.Item:      Described below.
26 *      Message:                Indicates that the body of the entire message should be fetched.
27 *                              Synonymous with FetchProfile.Item.BODY.
28 *      Part:                   Indicates that the given Part should be fetched. The provider
29 *                              is expected have previously created the given BodyPart and stored
30 *                              any information it needs to download the content.
31 * </pre>
32 */
33public class FetchProfile extends ArrayList<Fetchable> {
34    /**
35     * Default items available for pre-fetching. It should be expected that any
36     * item fetched by using these items could potentially include all of the
37     * previous items.
38     */
39    public enum Item implements Fetchable {
40        /**
41         * Download the flags of the message.
42         */
43        FLAGS,
44
45        /**
46         * Download the envelope of the message. This should include at minimum
47         * the size and the following headers: date, subject, from, content-type, to, cc
48         */
49        ENVELOPE,
50
51        /**
52         * Download the structure of the message. This maps directly to IMAP's BODYSTRUCTURE
53         * and may map to other providers.
54         * The provider should, if possible, fill in a properly formatted MIME structure in
55         * the message without actually downloading any message data. If the provider is not
56         * capable of this operation it should specifically set the body of the message to null
57         * so that upper levels can detect that a full body download is needed.
58         */
59        STRUCTURE,
60
61        /**
62         * A sane portion of the entire message, cut off at a provider determined limit.
63         * This should generaly be around 50kB.
64         */
65        BODY_SANE,
66
67        /**
68         * The entire message.
69         */
70        BODY,
71    }
72
73    /**
74     * @return the first {@link Part} in this collection, or null if it doesn't contain
75     * {@link Part}.
76     */
77    public Part getFirstPart() {
78        for (Fetchable o : this) {
79            if (o instanceof Part) {
80                return (Part) o;
81            }
82        }
83        return null;
84    }
85}
86