| /* |
| * Copyright (C) 2019 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.server.appsearch.impl; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.util.ArrayMap; |
| import android.util.ArraySet; |
| import android.util.SparseArray; |
| |
| import com.google.android.icing.proto.DocumentProto; |
| import com.google.android.icing.proto.PropertyProto; |
| import com.google.android.icing.proto.SearchResultProto; |
| |
| import java.util.Locale; |
| import java.util.Map; |
| import java.util.Set; |
| import java.util.concurrent.atomic.AtomicInteger; |
| |
| /** |
| * Fake in-memory implementation of the Icing key-value store and reverse index. |
| * <p> |
| * Currently, only queries by single exact term are supported. There is no support for persistence, |
| * namespaces, i18n tokenization, or schema. |
| */ |
| public class FakeIcing { |
| private final AtomicInteger mNextDocId = new AtomicInteger(); |
| private final Map<String, Integer> mUriToDocIdMap = new ArrayMap<>(); |
| /** Array of Documents where index into the array is the docId. */ |
| private final SparseArray<DocumentProto> mDocStore = new SparseArray<>(); |
| /** Map of term to posting-list (the set of DocIds containing that term). */ |
| private final Map<String, Set<Integer>> mIndex = new ArrayMap<>(); |
| |
| /** |
| * Inserts a document into the index. |
| * |
| * @param document The document to insert. |
| */ |
| public void put(@NonNull DocumentProto document) { |
| String uri = document.getUri(); |
| |
| // Update mDocIdMap |
| Integer docId = mUriToDocIdMap.get(uri); |
| if (docId != null) { |
| // Delete the old doc |
| mDocStore.remove(docId); |
| } |
| |
| // Allocate a new docId |
| docId = mNextDocId.getAndIncrement(); |
| mUriToDocIdMap.put(uri, docId); |
| |
| // Update mDocStore |
| mDocStore.put(docId, document); |
| |
| // Update mIndex |
| indexDocument(docId, document); |
| } |
| |
| /** |
| * Retrieves a document from the index. |
| * |
| * @param uri The URI of the document to retrieve. |
| * @return The body of the document, or {@code null} if no such document exists. |
| */ |
| @Nullable |
| public DocumentProto get(@NonNull String uri) { |
| Integer docId = mUriToDocIdMap.get(uri); |
| if (docId == null) { |
| return null; |
| } |
| return mDocStore.get(docId); |
| } |
| |
| /** |
| * Returns documents containing the given term. |
| * |
| * @param term A single exact term to look up in the index. |
| * @return A {@link SearchResultProto} containing the matching documents, which may have no |
| * results if no documents match. |
| */ |
| @NonNull |
| public SearchResultProto query(@NonNull String term) { |
| String normTerm = normalizeString(term); |
| Set<Integer> docIds = mIndex.get(normTerm); |
| if (docIds == null || docIds.isEmpty()) { |
| return SearchResultProto.getDefaultInstance(); |
| } |
| SearchResultProto.Builder results = SearchResultProto.newBuilder(); |
| for (int docId : docIds) { |
| DocumentProto document = mDocStore.get(docId); |
| if (document != null) { |
| results.addResults( |
| SearchResultProto.ResultProto.newBuilder().setDocument(document)); |
| } |
| } |
| return results.build(); |
| } |
| |
| /** |
| * Deletes a document by its URI. |
| * |
| * @param uri The URI of the document to be deleted. |
| */ |
| public void delete(@NonNull String uri) { |
| // Update mDocIdMap |
| Integer docId = mUriToDocIdMap.get(uri); |
| if (docId != null) { |
| // Delete the old doc |
| mDocStore.remove(docId); |
| mUriToDocIdMap.remove(uri); |
| } |
| } |
| |
| private void indexDocument(int docId, DocumentProto document) { |
| for (PropertyProto property : document.getPropertiesList()) { |
| for (String stringValue : property.getStringValuesList()) { |
| String[] words = normalizeString(stringValue).split("\\s+"); |
| for (String word : words) { |
| indexTerm(docId, word); |
| } |
| } |
| for (Long longValue : property.getInt64ValuesList()) { |
| indexTerm(docId, longValue.toString()); |
| } |
| for (Double doubleValue : property.getDoubleValuesList()) { |
| indexTerm(docId, doubleValue.toString()); |
| } |
| for (Boolean booleanValue : property.getBooleanValuesList()) { |
| indexTerm(docId, booleanValue.toString()); |
| } |
| // Intentionally skipping bytes values |
| for (DocumentProto documentValue : property.getDocumentValuesList()) { |
| indexDocument(docId, documentValue); |
| } |
| } |
| } |
| |
| private void indexTerm(int docId, String term) { |
| Set<Integer> postingList = mIndex.get(term); |
| if (postingList == null) { |
| postingList = new ArraySet<>(); |
| mIndex.put(term, postingList); |
| } |
| postingList.add(docId); |
| } |
| |
| /** Strips out punctuation and converts to lowercase. */ |
| private static String normalizeString(String input) { |
| return input.replaceAll("\\p{P}", "").toLowerCase(Locale.getDefault()); |
| } |
| } |