| /* |
| * Copyright (C) 2010 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License |
| */ |
| |
| package com.android.common.content; |
| |
| import java.util.Arrays; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| /** |
| * A convenience wrapper for a projection map. Makes it easier to create and use projection maps. |
| */ |
| public class ProjectionMap extends HashMap<String, String> { |
| |
| public static class Builder { |
| |
| private ProjectionMap mMap = new ProjectionMap(); |
| |
| public Builder add(String column) { |
| mMap.putColumn(column, column); |
| return this; |
| } |
| |
| public Builder add(String alias, String expression) { |
| mMap.putColumn(alias, expression + " AS " + alias); |
| return this; |
| } |
| |
| public Builder addAll(String[] columns) { |
| for (String column : columns) { |
| add(column); |
| } |
| return this; |
| } |
| |
| public Builder addAll(ProjectionMap map) { |
| for (Map.Entry<String, String> entry : map.entrySet()) { |
| mMap.putColumn(entry.getKey(), entry.getValue()); |
| } |
| return this; |
| } |
| |
| public ProjectionMap build() { |
| String[] columns = new String[mMap.size()]; |
| mMap.keySet().toArray(columns); |
| Arrays.sort(columns); |
| mMap.mColumns = columns; |
| return mMap; |
| } |
| |
| } |
| |
| private String[] mColumns; |
| |
| public static Builder builder() { |
| return new Builder(); |
| } |
| |
| /** |
| * Returns a sorted array of all column names in the projection map. |
| */ |
| public String[] getColumnNames() { |
| return mColumns; |
| } |
| |
| private void putColumn(String alias, String column) { |
| super.put(alias, column); |
| } |
| |
| @Override |
| public String put(String key, String value) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| public void putAll(Map<? extends String, ? extends String> map) { |
| throw new UnsupportedOperationException(); |
| } |
| } |