Extend DocumentsContract search to accept mime types
1. Add the key of query arguments and match method
in DocumentsContract.
2. Implement new querySearchDocuments method in
DocumentsProvider, ExternalStoragProvider and
FileSystemProvider.
Bug: 111786939
Test: Manual Test
Change-Id: I04e9f2be971f10ac1e9584a3486c948aaddea0a4
diff --git a/core/java/android/content/MimeTypeFilter.java b/core/java/android/content/MimeTypeFilter.java
new file mode 100644
index 0000000..1c26fd9
--- /dev/null
+++ b/core/java/android/content/MimeTypeFilter.java
@@ -0,0 +1,154 @@
+/*
+ * Copyright (C) 2018 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 android.content;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+
+import java.util.ArrayList;
+
+/**
+ * Provides utility methods for matching MIME type filters used in ContentProvider.
+ *
+ * <p>Wildcards are allowed only instead of the entire type or subtype with a tree prefix.
+ * Eg. image\/*, *\/* is a valid filter and will match image/jpeg, but image/j* is invalid and
+ * it will not match image/jpeg. Suffixes and parameters are not supported, and they are treated
+ * as part of the subtype during matching. Neither type nor subtype can be empty.
+ *
+ * <p><em>Note: MIME type matching in the Android framework is case-sensitive, unlike the formal
+ * RFC definitions. As a result, you should always write these elements with lower case letters,
+ * or use {@link android.content.Intent#normalizeMimeType} to ensure that they are converted to
+ * lower case.</em>
+ *
+ * <p>MIME types can be null or ill-formatted. In such case they won't match anything.
+ *
+ * <p>MIME type filters must be correctly formatted, or an exception will be thrown.
+ * Copied from support library.
+ * {@hide}
+ */
+public final class MimeTypeFilter {
+
+ private MimeTypeFilter() {
+ }
+
+ private static boolean mimeTypeAgainstFilter(
+ @NonNull String[] mimeTypeParts, @NonNull String[] filterParts) {
+ if (filterParts.length != 2) {
+ throw new IllegalArgumentException(
+ "Ill-formatted MIME type filter. Must be type/subtype.");
+ }
+ if (filterParts[0].isEmpty() || filterParts[1].isEmpty()) {
+ throw new IllegalArgumentException(
+ "Ill-formatted MIME type filter. Type or subtype empty.");
+ }
+ if (mimeTypeParts.length != 2) {
+ return false;
+ }
+ if (!"*".equals(filterParts[0])
+ && !filterParts[0].equals(mimeTypeParts[0])) {
+ return false;
+ }
+ if (!"*".equals(filterParts[1])
+ && !filterParts[1].equals(mimeTypeParts[1])) {
+ return false;
+ }
+
+ return true;
+ }
+
+ /**
+ * Matches one nullable MIME type against one MIME type filter.
+ * @return True if the {@code mimeType} matches the {@code filter}.
+ */
+ public static boolean matches(@Nullable String mimeType, @NonNull String filter) {
+ if (mimeType == null) {
+ return false;
+ }
+
+ final String[] mimeTypeParts = mimeType.split("/");
+ final String[] filterParts = filter.split("/");
+
+ return mimeTypeAgainstFilter(mimeTypeParts, filterParts);
+ }
+
+ /**
+ * Matches one nullable MIME type against an array of MIME type filters.
+ * @return The first matching filter, or null if nothing matches.
+ */
+ @Nullable
+ public static String matches(
+ @Nullable String mimeType, @NonNull String[] filters) {
+ if (mimeType == null) {
+ return null;
+ }
+
+ final String[] mimeTypeParts = mimeType.split("/");
+ for (String filter : filters) {
+ final String[] filterParts = filter.split("/");
+ if (mimeTypeAgainstFilter(mimeTypeParts, filterParts)) {
+ return filter;
+ }
+ }
+
+ return null;
+ }
+
+ /**
+ * Matches multiple MIME types against an array of MIME type filters.
+ * @return The first matching MIME type, or null if nothing matches.
+ */
+ @Nullable
+ public static String matches(
+ @Nullable String[] mimeTypes, @NonNull String filter) {
+ if (mimeTypes == null) {
+ return null;
+ }
+
+ final String[] filterParts = filter.split("/");
+ for (String mimeType : mimeTypes) {
+ final String[] mimeTypeParts = mimeType.split("/");
+ if (mimeTypeAgainstFilter(mimeTypeParts, filterParts)) {
+ return mimeType;
+ }
+ }
+
+ return null;
+ }
+
+ /**
+ * Matches multiple MIME types against an array of MIME type filters.
+ * @return The list of matching MIME types, or empty array if nothing matches.
+ */
+ @NonNull
+ public static String[] matchesMany(
+ @Nullable String[] mimeTypes, @NonNull String filter) {
+ if (mimeTypes == null) {
+ return new String[] {};
+ }
+
+ final ArrayList<String> list = new ArrayList<>();
+ final String[] filterParts = filter.split("/");
+ for (String mimeType : mimeTypes) {
+ final String[] mimeTypeParts = mimeType.split("/");
+ if (mimeTypeAgainstFilter(mimeTypeParts, filterParts)) {
+ list.add(mimeType);
+ }
+ }
+
+ return list.toArray(new String[list.size()]);
+ }
+}