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 */ 16package com.android.mail.utils; 17 18import android.database.MatrixCursor; 19 20import java.util.HashMap; 21import java.util.Map; 22 23public 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 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 37 public MatrixCursorWithCachedColumns(final String[] columnNames) { 38 this(columnNames, 16); 39 } 40 41 @Override 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