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 package com.android.mail.utils;
17 
18 import android.database.MatrixCursor;
19 
20 import java.util.HashMap;
21 import java.util.Map;
22 
23 public class MatrixCursorWithCachedColumns extends MatrixCursor {
24     /** A mapping of column names to column indices, to speed up lookups */
25     private final Map<String, Integer> mColumnNameMap;
26 
MatrixCursorWithCachedColumns(final String[] columnNames, final int initialCapacity)27     public MatrixCursorWithCachedColumns(final String[] columnNames, final int initialCapacity) {
28         super(columnNames, initialCapacity);
29 
30         final int columnCount = columnNames.length;
31         mColumnNameMap = new HashMap<String, Integer>(columnCount, 1);
32         for (int i = 0; i < columnCount; i++) {
33             mColumnNameMap.put(columnNames[i], i);
34         }
35     }
36 
MatrixCursorWithCachedColumns(final String[] columnNames)37     public MatrixCursorWithCachedColumns(final String[] columnNames) {
38         this(columnNames, 16);
39     }
40 
41     @Override
getColumnIndex(String columnName)42     public int getColumnIndex(String columnName) {
43         final Integer i = mColumnNameMap.get(columnName);
44         if (i != null) {
45             return i.intValue();
46         }
47 
48         return -1;
49     }
50 }
51