1/*
2 * Copyright (C) 2013 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.documentsui;
18
19import android.database.AbstractCursor;
20import android.database.Cursor;
21import android.os.Bundle;
22
23/**
24 * Cursor wrapper that adds columns to identify which root a document came from.
25 */
26public class RootCursorWrapper extends AbstractCursor {
27    private final String mAuthority;
28    private final String mRootId;
29
30    private final Cursor mCursor;
31    private final int mCount;
32
33    private final String[] mColumnNames;
34
35    private final int mAuthorityIndex;
36    private final int mRootIdIndex;
37
38    public static final String COLUMN_AUTHORITY = "android:authority";
39    public static final String COLUMN_ROOT_ID = "android:rootId";
40
41    public RootCursorWrapper(String authority, String rootId, Cursor cursor, int maxCount) {
42        mAuthority = authority;
43        mRootId = rootId;
44        mCursor = cursor;
45
46        final int count = cursor.getCount();
47        if (maxCount > 0 && count > maxCount) {
48            mCount = maxCount;
49        } else {
50            mCount = count;
51        }
52
53        if (cursor.getColumnIndex(COLUMN_AUTHORITY) != -1
54                || cursor.getColumnIndex(COLUMN_ROOT_ID) != -1) {
55            throw new IllegalArgumentException("Cursor contains internal columns!");
56        }
57        final String[] before = cursor.getColumnNames();
58        mColumnNames = new String[before.length + 2];
59        System.arraycopy(before, 0, mColumnNames, 0, before.length);
60        mAuthorityIndex = before.length;
61        mRootIdIndex = before.length + 1;
62        mColumnNames[mAuthorityIndex] = COLUMN_AUTHORITY;
63        mColumnNames[mRootIdIndex] = COLUMN_ROOT_ID;
64    }
65
66    @Override
67    public Bundle getExtras() {
68        return mCursor.getExtras();
69    }
70
71    @Override
72    public void close() {
73        super.close();
74        mCursor.close();
75    }
76
77    @Override
78    public boolean onMove(int oldPosition, int newPosition) {
79        return mCursor.moveToPosition(newPosition);
80    }
81
82    @Override
83    public String[] getColumnNames() {
84        return mColumnNames;
85    }
86
87    @Override
88    public int getCount() {
89        return mCount;
90    }
91
92    @Override
93    public double getDouble(int column) {
94        return mCursor.getDouble(column);
95    }
96
97    @Override
98    public float getFloat(int column) {
99        return mCursor.getFloat(column);
100    }
101
102    @Override
103    public int getInt(int column) {
104        return mCursor.getInt(column);
105    }
106
107    @Override
108    public long getLong(int column) {
109        return mCursor.getLong(column);
110    }
111
112    @Override
113    public short getShort(int column) {
114        return mCursor.getShort(column);
115    }
116
117    @Override
118    public String getString(int column) {
119        if (column == mAuthorityIndex) {
120            return mAuthority;
121        } else if (column == mRootIdIndex) {
122            return mRootId;
123        } else {
124            return mCursor.getString(column);
125        }
126    }
127
128    @Override
129    public int getType(int column) {
130        return mCursor.getType(column);
131    }
132
133    @Override
134    public boolean isNull(int column) {
135        return mCursor.isNull(column);
136    }
137}
138