FolderOperation.java revision 2a4be2459962700e1a38ba897de5d2f5913412f5 
1/*
2 * Copyright (C) 2012 Google Inc.
3 * Licensed to The Android Open Source Project.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *      http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18package com.android.mail.ui;
19
20import android.os.Parcel;
21import android.os.Parcelable;
22
23import com.android.mail.providers.Folder;
24import com.google.common.base.Objects;
25import com.google.common.collect.ImmutableList;
26
27import java.util.ArrayList;
28import java.util.Collection;
29import java.util.Collections;
30import java.util.HashSet;
31
32public class FolderOperation implements Parcelable {
33    /** An immutable, empty conversation list */
34    public static final Collection<FolderOperation> EMPTY = Collections.emptyList();
35    public final Folder mFolder;
36    public final boolean mAdd;
37
38    public FolderOperation(Folder folder, Boolean operation) {
39        mAdd = operation;
40        mFolder = folder;
41    }
42
43    /**
44     * Get all the unique folders associated with a set of folder operations.
45     * @param ops Operations to inspect
46     * @return ArrayList of Folder objects
47     */
48    public static ArrayList<Folder> getFolders(Collection<FolderOperation> ops) {
49        HashSet<Folder> folders = new HashSet<Folder>();
50        for (FolderOperation op : ops) {
51            folders.add(op.mFolder);
52        }
53        return new ArrayList<Folder>(folders);
54    }
55
56    /**
57     * Returns a collection of a single FolderOperation. This method always
58     * returns a valid collection even if the input folder is null.
59     *
60     * @param in a FolderOperation, possibly null.
61     * @return a collection of the folder.
62     */
63    public static Collection<FolderOperation> listOf(FolderOperation in) {
64        final Collection<FolderOperation> target = (in == null) ? EMPTY : ImmutableList.of(in);
65        return target;
66    }
67
68    /**
69     * Return if a set of folder operations removes the specified folder or adds
70     * inbox to a trashed conversation, making it a destructive operation.
71     */
72    public static boolean isDestructive(Collection<FolderOperation> folderOps, Folder folder) {
73        for (FolderOperation op : folderOps) {
74            if (Objects.equal(op.mFolder, folder) && !op.mAdd) {
75                return true;
76            }
77            if (folder.isTrash() && op.mFolder.isInbox()) {
78                return true;
79            }
80        }
81        return false;
82    }
83
84    // implements Parcelable
85
86    FolderOperation(Parcel in) {
87        mAdd = in.readByte() != 0;
88        mFolder = in.readParcelable(getClass().getClassLoader());
89    }
90
91    @Override
92    public int describeContents() {
93        return 0;
94    }
95
96    @Override
97    public void writeToParcel(Parcel dest, int flags) {
98        dest.writeByte((byte)(mAdd ? 1 : 0));
99        dest.writeParcelable(mFolder, 0);
100    }
101
102    public static final Creator<FolderOperation> CREATOR = new Creator<FolderOperation>() {
103        @Override
104        public FolderOperation createFromParcel(Parcel source) {
105            return new FolderOperation(source);
106        }
107
108        @Override
109        public FolderOperation[] newArray(int size) {
110            return new FolderOperation[size];
111        }
112    };
113}
114