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+/*
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+ * Copyright (C) 2013 The Android Open Source Project
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+ *
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+ * Licensed under the Apache License, Version 2.0 (the "License");
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+ * you may not use this file except in compliance with the License.
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+ * You may obtain a copy of the License at
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+ *
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+ * http://www.apache.org/licenses/LICENSE-2.0
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+ *
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+ * Unless required by applicable law or agreed to in writing, software
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+ * distributed under the License is distributed on an "AS IS" BASIS,
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+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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+ * See the License for the specific language governing permissions and
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+ * limitations under the License.
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+ */
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+
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+package androidx.core.content;
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+
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+import static org.xmlpull.v1.XmlPullParser.END_DOCUMENT;
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+import static org.xmlpull.v1.XmlPullParser.START_TAG;
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+
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+import android.content.ContentProvider;
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+import android.content.ContentValues;
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+import android.content.Context;
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+import android.content.Intent;
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+import android.content.pm.PackageManager;
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+import android.content.pm.ProviderInfo;
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+import android.content.res.XmlResourceParser;
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+import android.database.Cursor;
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+import android.database.MatrixCursor;
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+import android.net.Uri;
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+import android.os.Build;
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+import android.os.Environment;
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+import android.os.ParcelFileDescriptor;
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+import android.provider.OpenableColumns;
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+import android.support.annotation.NonNull;
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+import android.support.annotation.Nullable;
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+import android.support.v4.content.ContextCompat;
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+import android.text.TextUtils;
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+import android.webkit.MimeTypeMap;
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+
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+import org.xmlpull.v1.XmlPullParserException;
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+
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+import java.io.File;
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+import java.io.FileNotFoundException;
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+import java.io.IOException;
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+import java.util.HashMap;
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+import java.util.Map;
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+
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+import javax.annotation.concurrent.GuardedBy;
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+
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+/**
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+ * FileProvider is a special subclass of {@link ContentProvider} that facilitates secure sharing
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+ * of files associated with an app by creating a <code>content://</code> {@link Uri} for a file
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+ * instead of a <code>file:///</code> {@link Uri}.
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+ * <p>
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+ * A content URI allows you to grant read and write access using
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+ * temporary access permissions. When you create an {@link Intent} containing
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+ * a content URI, in order to send the content URI
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+ * to a client app, you can also call {@link Intent#setFlags(int) Intent.setFlags()} to add
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+ * permissions. These permissions are available to the client app for as long as the stack for
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+ * a receiving {@link android.app.Activity} is active. For an {@link Intent} going to a
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+ * {@link android.app.Service}, the permissions are available as long as the
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+ * {@link android.app.Service} is running.
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+ * <p>
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+ * In comparison, to control access to a <code>file:///</code> {@link Uri} you have to modify the
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+ * file system permissions of the underlying file. The permissions you provide become available to
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+ * <em>any</em> app, and remain in effect until you change them. This level of access is
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+ * fundamentally insecure.
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+ * <p>
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+ * The increased level of file access security offered by a content URI
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+ * makes FileProvider a key part of Android's security infrastructure.
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+ * <p>
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+ * This overview of FileProvider includes the following topics:
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+ * </p>
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+ * <ol>
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+ * <li><a href="#ProviderDefinition">Defining a FileProvider</a></li>
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+ * <li><a href="#SpecifyFiles">Specifying Available Files</a></li>
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+ * <li><a href="#GetUri">Retrieving the Content URI for a File</li>
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+ * <li><a href="#Permissions">Granting Temporary Permissions to a URI</a></li>
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+ * <li><a href="#ServeUri">Serving a Content URI to Another App</a></li>
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+ * </ol>
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+ * <h3 id="ProviderDefinition">Defining a FileProvider</h3>
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+ * <p>
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+ * Since the default functionality of FileProvider includes content URI generation for files, you
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+ * don't need to define a subclass in code. Instead, you can include a FileProvider in your app
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+ * by specifying it entirely in XML. To specify the FileProvider component itself, add a
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+ * <code><a href="{@docRoot}guide/topics/manifest/provider-element.html"><provider></a></code>
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+ * element to your app manifest. Set the <code>android:name</code> attribute to
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+ * <code>FileProvider</code>. Set the <code>android:authorities</code>
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+ * attribute to a URI authority based on a domain you control; for example, if you control the
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+ * domain <code>mydomain.com</code> you should use the authority
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+ * <code>com.mydomain.fileprovider</code>. Set the <code>android:exported</code> attribute to
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+ * <code>false</code>; the FileProvider does not need to be public. Set the
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+ * <a href="{@docRoot}guide/topics/manifest/provider-element.html#gprmsn"
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+ * >android:grantUriPermissions</a> attribute to <code>true</code>, to allow you
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+ * to grant temporary access to files. For example:
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+ * <pre class="prettyprint">
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+ *<manifest>
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+ * ...
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+ * <application>
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+ * ...
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+ * <provider
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+ * android:name="FileProvider"
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+ * android:authorities="com.mydomain.fileprovider"
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+ * android:exported="false"
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+ * android:grantUriPermissions="true">
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+ * ...
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+ * </provider>
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+ * ...
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+ * </application>
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+ *</manifest></pre>
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+ * <p>
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+ * If you want to override any of the default behavior of FileProvider methods, extend
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+ * the FileProvider class and use the fully-qualified class name in the <code>android:name</code>
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+ * attribute of the <code><provider></code> element.
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+ * <h3 id="SpecifyFiles">Specifying Available Files</h3>
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+ * A FileProvider can only generate a content URI for files in directories that you specify
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+ * beforehand. To specify a directory, specify the its storage area and path in XML, using child
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+ * elements of the <code><paths></code> element.
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+ * For example, the following <code>paths</code> element tells FileProvider that you intend to
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+ * request content URIs for the <code>images/</code> subdirectory of your private file area.
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+ * <pre class="prettyprint">
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+ *<paths xmlns:android="http://schemas.android.com/apk/res/android">
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+ * <files-path name="my_images" path="images/"/>
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+ * ...
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+ *</paths>
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+ *</pre>
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+ * <p>
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+ * The <code><paths></code> element must contain one or more of the following child elements:
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+ * </p>
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+ * <dl>
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+ * <dt>
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+ * <pre class="prettyprint">
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+ *<files-path name="<i>name</i>" path="<i>path</i>" />
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+ *</pre>
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+ * </dt>
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+ * <dd>
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+ * Represents files in the <code>files/</code> subdirectory of your app's internal storage
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+ * area. This subdirectory is the same as the value returned by {@link Context#getFilesDir()
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+ * Context.getFilesDir()}.
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+ * </dd>
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+ * <dt>
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+ * <pre>
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+ *<cache-path name="<i>name</i>" path="<i>path</i>" />
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+ *</pre>
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+ * <dt>
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+ * <dd>
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+ * Represents files in the cache subdirectory of your app's internal storage area. The root path
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+ * of this subdirectory is the same as the value returned by {@link Context#getCacheDir()
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+ * getCacheDir()}.
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+ * </dd>
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+ * <dt>
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+ * <pre class="prettyprint">
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+ *<external-path name="<i>name</i>" path="<i>path</i>" />
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+ *</pre>
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+ * </dt>
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+ * <dd>
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+ * Represents files in the root of the external storage area. The root path of this subdirectory
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+ * is the same as the value returned by
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+ * {@link Environment#getExternalStorageDirectory() Environment.getExternalStorageDirectory()}.
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+ * </dd>
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+ * <dt>
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+ * <pre class="prettyprint">
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+ *<external-files-path name="<i>name</i>" path="<i>path</i>" />
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+ *</pre>
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+ * </dt>
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+ * <dd>
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+ * Represents files in the root of your app's external storage area. The root path of this
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+ * subdirectory is the same as the value returned by
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+ * {@code Context#getExternalFilesDir(String) Context.getExternalFilesDir(null)}.
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+ * </dd>
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+ * <dt>
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+ * <pre class="prettyprint">
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+ *<external-cache-path name="<i>name</i>" path="<i>path</i>" />
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+ *</pre>
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+ * </dt>
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+ * <dd>
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+ * Represents files in the root of your app's external cache area. The root path of this
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+ * subdirectory is the same as the value returned by
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+ * {@link Context#getExternalCacheDir() Context.getExternalCacheDir()}.
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+ * </dd>
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+ * <dt>
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+ * <pre class="prettyprint">
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+ *<external-media-path name="<i>name</i>" path="<i>path</i>" />
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+ *</pre>
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+ * </dt>
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+ * <dd>
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+ * Represents files in the root of your app's external media area. The root path of this
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+ * subdirectory is the same as the value returned by the first result of
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+ * {@link Context#getExternalMediaDirs() Context.getExternalMediaDirs()}.
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+ * <p><strong>Note:</strong> this directory is only available on API 21+ devices.</p>
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+ * </dd>
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+ * </dl>
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+ * <p>
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+ * These child elements all use the same attributes:
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+ * </p>
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+ * <dl>
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+ * <dt>
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+ * <code>name="<i>name</i>"</code>
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+ * </dt>
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+ * <dd>
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+ * A URI path segment. To enforce security, this value hides the name of the subdirectory
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+ * you're sharing. The subdirectory name for this value is contained in the
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+ * <code>path</code> attribute.
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+ * </dd>
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+ * <dt>
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+ * <code>path="<i>path</i>"</code>
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+ * </dt>
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+ * <dd>
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+ * The subdirectory you're sharing. While the <code>name</code> attribute is a URI path
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+ * segment, the <code>path</code> value is an actual subdirectory name. Notice that the
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+ * value refers to a <b>subdirectory</b>, not an individual file or files. You can't
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+ * share a single file by its file name, nor can you specify a subset of files using
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+ * wildcards.
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+ * </dd>
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+ * </dl>
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+ * <p>
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+ * You must specify a child element of <code><paths></code> for each directory that contains
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+ * files for which you want content URIs. For example, these XML elements specify two directories:
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+ * <pre class="prettyprint">
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+ *<paths xmlns:android="http://schemas.android.com/apk/res/android">
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+ * <files-path name="my_images" path="images/"/>
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+ * <files-path name="my_docs" path="docs/"/>
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+ *</paths>
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+ *</pre>
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+ * <p>
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+ * Put the <code><paths></code> element and its children in an XML file in your project.
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+ * For example, you can add them to a new file called <code>res/xml/file_paths.xml</code>.
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+ * To link this file to the FileProvider, add a
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+ * <a href="{@docRoot}guide/topics/manifest/meta-data-element.html"><meta-data></a> element
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+ * as a child of the <code><provider></code> element that defines the FileProvider. Set the
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+ * <code><meta-data></code> element's "android:name" attribute to
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+ * <code>android.support.FILE_PROVIDER_PATHS</code>. Set the element's "android:resource" attribute
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+ * to <code>@xml/file_paths</code> (notice that you don't specify the <code>.xml</code>
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+ * extension). For example:
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+ * <pre class="prettyprint">
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+ *<provider
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+ * android:name="FileProvider"
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+ * android:authorities="com.mydomain.fileprovider"
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+ * android:exported="false"
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+ * android:grantUriPermissions="true">
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+ * <meta-data
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+ * android:name="android.support.FILE_PROVIDER_PATHS"
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+ * android:resource="@xml/file_paths" />
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+ *</provider>
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+ *</pre>
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+ * <h3 id="GetUri">Generating the Content URI for a File</h3>
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+ * <p>
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+ * To share a file with another app using a content URI, your app has to generate the content URI.
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+ * To generate the content URI, create a new {@link File} for the file, then pass the {@link File}
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+ * to {@link #getUriForFile(Context, String, File) getUriForFile()}. You can send the content URI
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+ * returned by {@link #getUriForFile(Context, String, File) getUriForFile()} to another app in an
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+ * {@link Intent}. The client app that receives the content URI can open the file
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+ * and access its contents by calling
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+ * {@link android.content.ContentResolver#openFileDescriptor(Uri, String)
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+ * ContentResolver.openFileDescriptor} to get a {@link ParcelFileDescriptor}.
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+ * <p>
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+ * For example, suppose your app is offering files to other apps with a FileProvider that has the
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+ * authority <code>com.mydomain.fileprovider</code>. To get a content URI for the file
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+ * <code>default_image.jpg</code> in the <code>images/</code> subdirectory of your internal storage
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+ * add the following code:
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+ * <pre class="prettyprint">
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+ *File imagePath = new File(Context.getFilesDir(), "images");
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+ *File newFile = new File(imagePath, "default_image.jpg");
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+ *Uri contentUri = getUriForFile(getContext(), "com.mydomain.fileprovider", newFile);
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+ *</pre>
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+ * As a result of the previous snippet,
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+ * {@link #getUriForFile(Context, String, File) getUriForFile()} returns the content URI
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+ * <code>content://com.mydomain.fileprovider/my_images/default_image.jpg</code>.
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+ * <h3 id="Permissions">Granting Temporary Permissions to a URI</h3>
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+ * To grant an access permission to a content URI returned from
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+ * {@link #getUriForFile(Context, String, File) getUriForFile()}, do one of the following:
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+ * <ul>
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+ * <li>
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+ * Call the method
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+ * {@link Context#grantUriPermission(String, Uri, int)
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+ * Context.grantUriPermission(package, Uri, mode_flags)} for the <code>content://</code>
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+ * {@link Uri}, using the desired mode flags. This grants temporary access permission for the
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+ * content URI to the specified package, according to the value of the
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+ * the <code>mode_flags</code> parameter, which you can set to
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+ * {@link Intent#FLAG_GRANT_READ_URI_PERMISSION}, {@link Intent#FLAG_GRANT_WRITE_URI_PERMISSION}
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+ * or both. The permission remains in effect until you revoke it by calling
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+ * {@link Context#revokeUriPermission(Uri, int) revokeUriPermission()} or until the device
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+ * reboots.
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+ * </li>
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+ * <li>
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+ * Put the content URI in an {@link Intent} by calling {@link Intent#setData(Uri) setData()}.
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+ * </li>
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+ * <li>
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+ * Next, call the method {@link Intent#setFlags(int) Intent.setFlags()} with either
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+ * {@link Intent#FLAG_GRANT_READ_URI_PERMISSION} or
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+ * {@link Intent#FLAG_GRANT_WRITE_URI_PERMISSION} or both.
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+ * </li>
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+ * <li>
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+ * Finally, send the {@link Intent} to
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+ * another app. Most often, you do this by calling
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+ * {@link android.app.Activity#setResult(int, Intent) setResult()}.
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+ * <p>
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+ * Permissions granted in an {@link Intent} remain in effect while the stack of the receiving
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+ * {@link android.app.Activity} is active. When the stack finishes, the permissions are
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+ * automatically removed. Permissions granted to one {@link android.app.Activity} in a client
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+ * app are automatically extended to other components of that app.
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+ * </p>
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+ * </li>
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+ * </ul>
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+ * <h3 id="ServeUri">Serving a Content URI to Another App</h3>
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+ * <p>
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+ * There are a variety of ways to serve the content URI for a file to a client app. One common way
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+ * is for the client app to start your app by calling
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+ * {@link android.app.Activity#startActivityForResult(Intent, int, Bundle) startActivityResult()},
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+ * which sends an {@link Intent} to your app to start an {@link android.app.Activity} in your app.
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+ * In response, your app can immediately return a content URI to the client app or present a user
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+ * interface that allows the user to pick a file. In the latter case, once the user picks the file
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+ * your app can return its content URI. In both cases, your app returns the content URI in an
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+ * {@link Intent} sent via {@link android.app.Activity#setResult(int, Intent) setResult()}.
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+ * </p>
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+ * <p>
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+ * You can also put the content URI in a {@link android.content.ClipData} object and then add the
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+ * object to an {@link Intent} you send to a client app. To do this, call
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+ * {@link Intent#setClipData(ClipData) Intent.setClipData()}. When you use this approach, you can
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+ * add multiple {@link android.content.ClipData} objects to the {@link Intent}, each with its own
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+ * content URI. When you call {@link Intent#setFlags(int) Intent.setFlags()} on the {@link Intent}
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+ * to set temporary access permissions, the same permissions are applied to all of the content
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+ * URIs.
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+ * </p>
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+ * <p class="note">
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+ * <strong>Note:</strong> The {@link Intent#setClipData(ClipData) Intent.setClipData()} method is
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+ * only available in platform version 16 (Android 4.1) and later. If you want to maintain
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+ * compatibility with previous versions, you should send one content URI at a time in the
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+ * {@link Intent}. Set the action to {@link Intent#ACTION_SEND} and put the URI in data by calling
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+ * {@link Intent#setData setData()}.
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+ * </p>
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+ * <h3 id="">More Information</h3>
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+ * <p>
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+ * To learn more about FileProvider, see the Android training class
|
|
|
+ * <a href="{@docRoot}training/secure-file-sharing/index.html">Sharing Files Securely with URIs</a>.
|
|
|
+ * </p>
|
|
|
+ */
|
|
|
+public class FileProvider extends ContentProvider {
|
|
|
+ private static final String[] COLUMNS = {
|
|
|
+ OpenableColumns.DISPLAY_NAME, OpenableColumns.SIZE };
|
|
|
+
|
|
|
+ private static final String
|
|
|
+ META_DATA_FILE_PROVIDER_PATHS = "android.support.FILE_PROVIDER_PATHS";
|
|
|
+
|
|
|
+ private static final String TAG_ROOT_PATH = "root-path";
|
|
|
+ private static final String TAG_FILES_PATH = "files-path";
|
|
|
+ private static final String TAG_CACHE_PATH = "cache-path";
|
|
|
+ private static final String TAG_EXTERNAL = "external-path";
|
|
|
+ private static final String TAG_EXTERNAL_FILES = "external-files-path";
|
|
|
+ private static final String TAG_EXTERNAL_CACHE = "external-cache-path";
|
|
|
+ private static final String TAG_EXTERNAL_MEDIA = "external-media-path";
|
|
|
+
|
|
|
+ private static final String ATTR_NAME = "name";
|
|
|
+ private static final String ATTR_PATH = "path";
|
|
|
+
|
|
|
+ private static final File DEVICE_ROOT = new File("/");
|
|
|
+
|
|
|
+ @GuardedBy("sCache")
|
|
|
+ private static HashMap<String, PathStrategy> sCache = new HashMap<String, PathStrategy>();
|
|
|
+
|
|
|
+ private PathStrategy mStrategy;
|
|
|
+
|
|
|
+ /**
|
|
|
+ * The default FileProvider implementation does not need to be initialized. If you want to
|
|
|
+ * override this method, you must provide your own subclass of FileProvider.
|
|
|
+ */
|
|
|
+ @Override
|
|
|
+ public boolean onCreate() {
|
|
|
+ return true;
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * After the FileProvider is instantiated, this method is called to provide the system with
|
|
|
+ * information about the provider.
|
|
|
+ *
|
|
|
+ * @param context A {@link Context} for the current component.
|
|
|
+ * @param info A {@link ProviderInfo} for the new provider.
|
|
|
+ */
|
|
|
+ @Override
|
|
|
+ public void attachInfo(@NonNull Context context, @NonNull ProviderInfo info) {
|
|
|
+ super.attachInfo(context, info);
|
|
|
+
|
|
|
+ // Sanity check our security
|
|
|
+ if (info.exported) {
|
|
|
+ throw new SecurityException("Provider must not be exported");
|
|
|
+ }
|
|
|
+ if (!info.grantUriPermissions) {
|
|
|
+ throw new SecurityException("Provider must grant uri permissions");
|
|
|
+ }
|
|
|
+
|
|
|
+ mStrategy = getPathStrategy(context, info.authority);
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * Return a content URI for a given {@link File}. Specific temporary
|
|
|
+ * permissions for the content URI can be set with
|
|
|
+ * {@link Context#grantUriPermission(String, Uri, int)}, or added
|
|
|
+ * to an {@link Intent} by calling {@link Intent#setData(Uri) setData()} and then
|
|
|
+ * {@link Intent#setFlags(int) setFlags()}; in both cases, the applicable flags are
|
|
|
+ * {@link Intent#FLAG_GRANT_READ_URI_PERMISSION} and
|
|
|
+ * {@link Intent#FLAG_GRANT_WRITE_URI_PERMISSION}. A FileProvider can only return a
|
|
|
+ * <code>content</code> {@link Uri} for file paths defined in their <code><paths></code>
|
|
|
+ * meta-data element. See the Class Overview for more information.
|
|
|
+ *
|
|
|
+ * @param context A {@link Context} for the current component.
|
|
|
+ * @param authority The authority of a {@link FileProvider} defined in a
|
|
|
+ * {@code <provider>} element in your app's manifest.
|
|
|
+ * @param file A {@link File} pointing to the filename for which you want a
|
|
|
+ * <code>content</code> {@link Uri}.
|
|
|
+ * @return A content URI for the file.
|
|
|
+ * @throws IllegalArgumentException When the given {@link File} is outside
|
|
|
+ * the paths supported by the provider.
|
|
|
+ */
|
|
|
+ public static Uri getUriForFile(@NonNull Context context, @NonNull String authority,
|
|
|
+ @NonNull File file) {
|
|
|
+ final PathStrategy strategy = getPathStrategy(context, authority);
|
|
|
+ return strategy.getUriForFile(file);
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * Use a content URI returned by
|
|
|
+ * {@link #getUriForFile(Context, String, File) getUriForFile()} to get information about a file
|
|
|
+ * managed by the FileProvider.
|
|
|
+ * FileProvider reports the column names defined in {@link OpenableColumns}:
|
|
|
+ * <ul>
|
|
|
+ * <li>{@link OpenableColumns#DISPLAY_NAME}</li>
|
|
|
+ * <li>{@link OpenableColumns#SIZE}</li>
|
|
|
+ * </ul>
|
|
|
+ * For more information, see
|
|
|
+ * {@link ContentProvider#query(Uri, String[], String, String[], String)
|
|
|
+ * ContentProvider.query()}.
|
|
|
+ *
|
|
|
+ * @param uri A content URI returned by {@link #getUriForFile}.
|
|
|
+ * @param projection The list of columns to put into the {@link Cursor}. If null all columns are
|
|
|
+ * included.
|
|
|
+ * @param selection Selection criteria to apply. If null then all data that matches the content
|
|
|
+ * URI is returned.
|
|
|
+ * @param selectionArgs An array of {@link String}, containing arguments to bind to
|
|
|
+ * the <i>selection</i> parameter. The <i>query</i> method scans <i>selection</i> from left to
|
|
|
+ * right and iterates through <i>selectionArgs</i>, replacing the current "?" character in
|
|
|
+ * <i>selection</i> with the value at the current position in <i>selectionArgs</i>. The
|
|
|
+ * values are bound to <i>selection</i> as {@link String} values.
|
|
|
+ * @param sortOrder A {@link String} containing the column name(s) on which to sort
|
|
|
+ * the resulting {@link Cursor}.
|
|
|
+ * @return A {@link Cursor} containing the results of the query.
|
|
|
+ *
|
|
|
+ */
|
|
|
+ @Override
|
|
|
+ public Cursor query(@NonNull Uri uri, @Nullable String[] projection, @Nullable String selection,
|
|
|
+ @Nullable String[] selectionArgs,
|
|
|
+ @Nullable String sortOrder) {
|
|
|
+ // ContentProvider has already checked granted permissions
|
|
|
+ final File file = mStrategy.getFileForUri(uri);
|
|
|
+
|
|
|
+ if (projection == null) {
|
|
|
+ projection = COLUMNS;
|
|
|
+ }
|
|
|
+
|
|
|
+ String[] cols = new String[projection.length];
|
|
|
+ Object[] values = new Object[projection.length];
|
|
|
+ int i = 0;
|
|
|
+ for (String col : projection) {
|
|
|
+ if (OpenableColumns.DISPLAY_NAME.equals(col)) {
|
|
|
+ cols[i] = OpenableColumns.DISPLAY_NAME;
|
|
|
+ values[i++] = file.getName();
|
|
|
+ } else if (OpenableColumns.SIZE.equals(col)) {
|
|
|
+ cols[i] = OpenableColumns.SIZE;
|
|
|
+ values[i++] = file.length();
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ cols = copyOf(cols, i);
|
|
|
+ values = copyOf(values, i);
|
|
|
+
|
|
|
+ final MatrixCursor cursor = new MatrixCursor(cols, 1);
|
|
|
+ cursor.addRow(values);
|
|
|
+ return cursor;
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * Returns the MIME type of a content URI returned by
|
|
|
+ * {@link #getUriForFile(Context, String, File) getUriForFile()}.
|
|
|
+ *
|
|
|
+ * @param uri A content URI returned by
|
|
|
+ * {@link #getUriForFile(Context, String, File) getUriForFile()}.
|
|
|
+ * @return If the associated file has an extension, the MIME type associated with that
|
|
|
+ * extension; otherwise <code>application/octet-stream</code>.
|
|
|
+ */
|
|
|
+ @Override
|
|
|
+ public String getType(@NonNull Uri uri) {
|
|
|
+ // ContentProvider has already checked granted permissions
|
|
|
+ final File file = mStrategy.getFileForUri(uri);
|
|
|
+
|
|
|
+ final int lastDot = file.getName().lastIndexOf('.');
|
|
|
+ if (lastDot >= 0) {
|
|
|
+ final String extension = file.getName().substring(lastDot + 1);
|
|
|
+ final String mime = MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension);
|
|
|
+ if (mime != null) {
|
|
|
+ return mime;
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ return "application/octet-stream";
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * By default, this method throws an {@link UnsupportedOperationException}. You must
|
|
|
+ * subclass FileProvider if you want to provide different functionality.
|
|
|
+ */
|
|
|
+ @Override
|
|
|
+ public Uri insert(@NonNull Uri uri, ContentValues values) {
|
|
|
+ throw new UnsupportedOperationException("No external inserts");
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * By default, this method throws an {@link UnsupportedOperationException}. You must
|
|
|
+ * subclass FileProvider if you want to provide different functionality.
|
|
|
+ */
|
|
|
+ @Override
|
|
|
+ public int update(@NonNull Uri uri, ContentValues values, @Nullable String selection,
|
|
|
+ @Nullable String[] selectionArgs) {
|
|
|
+ throw new UnsupportedOperationException("No external updates");
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * Deletes the file associated with the specified content URI, as
|
|
|
+ * returned by {@link #getUriForFile(Context, String, File) getUriForFile()}. Notice that this
|
|
|
+ * method does <b>not</b> throw an {@link IOException}; you must check its return value.
|
|
|
+ *
|
|
|
+ * @param uri A content URI for a file, as returned by
|
|
|
+ * {@link #getUriForFile(Context, String, File) getUriForFile()}.
|
|
|
+ * @param selection Ignored. Set to {@code null}.
|
|
|
+ * @param selectionArgs Ignored. Set to {@code null}.
|
|
|
+ * @return 1 if the delete succeeds; otherwise, 0.
|
|
|
+ */
|
|
|
+ @Override
|
|
|
+ public int delete(@NonNull Uri uri, @Nullable String selection,
|
|
|
+ @Nullable String[] selectionArgs) {
|
|
|
+ // ContentProvider has already checked granted permissions
|
|
|
+ final File file = mStrategy.getFileForUri(uri);
|
|
|
+ return file.delete() ? 1 : 0;
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * By default, FileProvider automatically returns the
|
|
|
+ * {@link ParcelFileDescriptor} for a file associated with a <code>content://</code>
|
|
|
+ * {@link Uri}. To get the {@link ParcelFileDescriptor}, call
|
|
|
+ * {@link android.content.ContentResolver#openFileDescriptor(Uri, String)
|
|
|
+ * ContentResolver.openFileDescriptor}.
|
|
|
+ *
|
|
|
+ * To override this method, you must provide your own subclass of FileProvider.
|
|
|
+ *
|
|
|
+ * @param uri A content URI associated with a file, as returned by
|
|
|
+ * {@link #getUriForFile(Context, String, File) getUriForFile()}.
|
|
|
+ * @param mode Access mode for the file. May be "r" for read-only access, "rw" for read and
|
|
|
+ * write access, or "rwt" for read and write access that truncates any existing file.
|
|
|
+ * @return A new {@link ParcelFileDescriptor} with which you can access the file.
|
|
|
+ */
|
|
|
+ @Override
|
|
|
+ public ParcelFileDescriptor openFile(@NonNull Uri uri, @NonNull String mode)
|
|
|
+ throws FileNotFoundException {
|
|
|
+ // ContentProvider has already checked granted permissions
|
|
|
+ final File file = mStrategy.getFileForUri(uri);
|
|
|
+ final int fileMode = modeToMode(mode);
|
|
|
+ return ParcelFileDescriptor.open(file, fileMode);
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * Return {@link PathStrategy} for given authority, either by parsing or
|
|
|
+ * returning from cache.
|
|
|
+ */
|
|
|
+ private static PathStrategy getPathStrategy(Context context, String authority) {
|
|
|
+ PathStrategy strat;
|
|
|
+ synchronized (sCache) {
|
|
|
+ strat = sCache.get(authority);
|
|
|
+ if (strat == null) {
|
|
|
+ try {
|
|
|
+ strat = parsePathStrategy(context, authority);
|
|
|
+ } catch (IOException e) {
|
|
|
+ throw new IllegalArgumentException(
|
|
|
+ "Failed to parse " + META_DATA_FILE_PROVIDER_PATHS + " meta-data", e);
|
|
|
+ } catch (XmlPullParserException e) {
|
|
|
+ throw new IllegalArgumentException(
|
|
|
+ "Failed to parse " + META_DATA_FILE_PROVIDER_PATHS + " meta-data", e);
|
|
|
+ }
|
|
|
+ sCache.put(authority, strat);
|
|
|
+ }
|
|
|
+ }
|
|
|
+ return strat;
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * Parse and return {@link PathStrategy} for given authority as defined in
|
|
|
+ * {@link #META_DATA_FILE_PROVIDER_PATHS} {@code <meta-data>}.
|
|
|
+ *
|
|
|
+ * @see #getPathStrategy(Context, String)
|
|
|
+ */
|
|
|
+ private static PathStrategy parsePathStrategy(Context context, String authority)
|
|
|
+ throws IOException, XmlPullParserException {
|
|
|
+ final SimplePathStrategy strat = new SimplePathStrategy(authority);
|
|
|
+
|
|
|
+ final ProviderInfo info = context.getPackageManager()
|
|
|
+ .resolveContentProvider(authority, PackageManager.GET_META_DATA);
|
|
|
+ final XmlResourceParser in = info.loadXmlMetaData(
|
|
|
+ context.getPackageManager(), META_DATA_FILE_PROVIDER_PATHS);
|
|
|
+ if (in == null) {
|
|
|
+ throw new IllegalArgumentException(
|
|
|
+ "Missing " + META_DATA_FILE_PROVIDER_PATHS + " meta-data");
|
|
|
+ }
|
|
|
+
|
|
|
+ int type;
|
|
|
+ while ((type = in.next()) != END_DOCUMENT) {
|
|
|
+ if (type == START_TAG) {
|
|
|
+ final String tag = in.getName();
|
|
|
+
|
|
|
+ final String name = in.getAttributeValue(null, ATTR_NAME);
|
|
|
+ String path = in.getAttributeValue(null, ATTR_PATH);
|
|
|
+
|
|
|
+ File target = null;
|
|
|
+ if (TAG_ROOT_PATH.equals(tag)) {
|
|
|
+ target = DEVICE_ROOT;
|
|
|
+ } else if (TAG_FILES_PATH.equals(tag)) {
|
|
|
+ target = context.getFilesDir();
|
|
|
+ } else if (TAG_CACHE_PATH.equals(tag)) {
|
|
|
+ target = context.getCacheDir();
|
|
|
+ } else if (TAG_EXTERNAL.equals(tag)) {
|
|
|
+ target = Environment.getExternalStorageDirectory();
|
|
|
+ } else if (TAG_EXTERNAL_FILES.equals(tag)) {
|
|
|
+ File[] externalFilesDirs = ContextCompat.getExternalFilesDirs(context, null);
|
|
|
+ if (externalFilesDirs.length > 0) {
|
|
|
+ target = externalFilesDirs[0];
|
|
|
+ }
|
|
|
+ } else if (TAG_EXTERNAL_CACHE.equals(tag)) {
|
|
|
+ File[] externalCacheDirs = ContextCompat.getExternalCacheDirs(context);
|
|
|
+ if (externalCacheDirs.length > 0) {
|
|
|
+ target = externalCacheDirs[0];
|
|
|
+ }
|
|
|
+ } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP
|
|
|
+ && TAG_EXTERNAL_MEDIA.equals(tag)) {
|
|
|
+ File[] externalMediaDirs = context.getExternalMediaDirs();
|
|
|
+ if (externalMediaDirs.length > 0) {
|
|
|
+ target = externalMediaDirs[0];
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ if (target != null) {
|
|
|
+ strat.addRoot(name, buildPath(target, path));
|
|
|
+ }
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ return strat;
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * Strategy for mapping between {@link File} and {@link Uri}.
|
|
|
+ * <p>
|
|
|
+ * Strategies must be symmetric so that mapping a {@link File} to a
|
|
|
+ * {@link Uri} and then back to a {@link File} points at the original
|
|
|
+ * target.
|
|
|
+ * <p>
|
|
|
+ * Strategies must remain consistent across app launches, and not rely on
|
|
|
+ * dynamic state. This ensures that any generated {@link Uri} can still be
|
|
|
+ * resolved if your process is killed and later restarted.
|
|
|
+ *
|
|
|
+ * @see SimplePathStrategy
|
|
|
+ */
|
|
|
+ interface PathStrategy {
|
|
|
+ /**
|
|
|
+ * Return a {@link Uri} that represents the given {@link File}.
|
|
|
+ */
|
|
|
+ Uri getUriForFile(File file);
|
|
|
+
|
|
|
+ /**
|
|
|
+ * Return a {@link File} that represents the given {@link Uri}.
|
|
|
+ */
|
|
|
+ File getFileForUri(Uri uri);
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * Strategy that provides access to files living under a narrow whitelist of
|
|
|
+ * filesystem roots. It will throw {@link SecurityException} if callers try
|
|
|
+ * accessing files outside the configured roots.
|
|
|
+ * <p>
|
|
|
+ * For example, if configured with
|
|
|
+ * {@code addRoot("myfiles", context.getFilesDir())}, then
|
|
|
+ * {@code context.getFileStreamPath("foo.txt")} would map to
|
|
|
+ * {@code content://myauthority/myfiles/foo.txt}.
|
|
|
+ */
|
|
|
+ static class SimplePathStrategy implements PathStrategy {
|
|
|
+ private final String mAuthority;
|
|
|
+ private final HashMap<String, File> mRoots = new HashMap<String, File>();
|
|
|
+
|
|
|
+ SimplePathStrategy(String authority) {
|
|
|
+ mAuthority = authority;
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * Add a mapping from a name to a filesystem root. The provider only offers
|
|
|
+ * access to files that live under configured roots.
|
|
|
+ */
|
|
|
+ void addRoot(String name, File root) {
|
|
|
+ if (TextUtils.isEmpty(name)) {
|
|
|
+ throw new IllegalArgumentException("Name must not be empty");
|
|
|
+ }
|
|
|
+
|
|
|
+ try {
|
|
|
+ // Resolve to canonical path to keep path checking fast
|
|
|
+ root = root.getCanonicalFile();
|
|
|
+ } catch (IOException e) {
|
|
|
+ throw new IllegalArgumentException(
|
|
|
+ "Failed to resolve canonical path for " + root, e);
|
|
|
+ }
|
|
|
+
|
|
|
+ mRoots.put(name, root);
|
|
|
+ }
|
|
|
+
|
|
|
+ @Override
|
|
|
+ public Uri getUriForFile(File file) {
|
|
|
+ String path;
|
|
|
+ try {
|
|
|
+ path = file.getCanonicalPath();
|
|
|
+ } catch (IOException e) {
|
|
|
+ throw new IllegalArgumentException("Failed to resolve canonical path for " + file);
|
|
|
+ }
|
|
|
+
|
|
|
+ // Find the most-specific root path
|
|
|
+ Map.Entry<String, File> mostSpecific = null;
|
|
|
+ for (Map.Entry<String, File> root : mRoots.entrySet()) {
|
|
|
+ final String rootPath = root.getValue().getPath();
|
|
|
+ if (path.startsWith(rootPath) && (mostSpecific == null
|
|
|
+ || rootPath.length() > mostSpecific.getValue().getPath().length())) {
|
|
|
+ mostSpecific = root;
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ if (mostSpecific == null) {
|
|
|
+ throw new IllegalArgumentException(
|
|
|
+ "Failed to find configured root that contains " + path);
|
|
|
+ }
|
|
|
+
|
|
|
+ // Start at first char of path under root
|
|
|
+ final String rootPath = mostSpecific.getValue().getPath();
|
|
|
+ if (rootPath.endsWith("/")) {
|
|
|
+ path = path.substring(rootPath.length());
|
|
|
+ } else {
|
|
|
+ path = path.substring(rootPath.length() + 1);
|
|
|
+ }
|
|
|
+
|
|
|
+ // Encode the tag and path separately
|
|
|
+ path = Uri.encode(mostSpecific.getKey()) + '/' + Uri.encode(path, "/");
|
|
|
+ return new Uri.Builder().scheme("content")
|
|
|
+ .authority(mAuthority).encodedPath(path).build();
|
|
|
+ }
|
|
|
+
|
|
|
+ @Override
|
|
|
+ public File getFileForUri(Uri uri) {
|
|
|
+ String path = uri.getEncodedPath();
|
|
|
+
|
|
|
+ final int splitIndex = path.indexOf('/', 1);
|
|
|
+ final String tag = Uri.decode(path.substring(1, splitIndex));
|
|
|
+ path = Uri.decode(path.substring(splitIndex + 1));
|
|
|
+
|
|
|
+ final File root = mRoots.get(tag);
|
|
|
+ if (root == null) {
|
|
|
+ throw new IllegalArgumentException("Unable to find configured root for " + uri);
|
|
|
+ }
|
|
|
+
|
|
|
+ File file = new File(root, path);
|
|
|
+ try {
|
|
|
+ file = file.getCanonicalFile();
|
|
|
+ } catch (IOException e) {
|
|
|
+ throw new IllegalArgumentException("Failed to resolve canonical path for " + file);
|
|
|
+ }
|
|
|
+
|
|
|
+ if (!file.getPath().startsWith(root.getPath())) {
|
|
|
+ throw new SecurityException("Resolved path jumped beyond configured root");
|
|
|
+ }
|
|
|
+
|
|
|
+ return file;
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ /**
|
|
|
+ * Copied from ContentResolver.java
|
|
|
+ */
|
|
|
+ private static int modeToMode(String mode) {
|
|
|
+ int modeBits;
|
|
|
+ if ("r".equals(mode)) {
|
|
|
+ modeBits = ParcelFileDescriptor.MODE_READ_ONLY;
|
|
|
+ } else if ("w".equals(mode) || "wt".equals(mode)) {
|
|
|
+ modeBits = ParcelFileDescriptor.MODE_WRITE_ONLY
|
|
|
+ | ParcelFileDescriptor.MODE_CREATE
|
|
|
+ | ParcelFileDescriptor.MODE_TRUNCATE;
|
|
|
+ } else if ("wa".equals(mode)) {
|
|
|
+ modeBits = ParcelFileDescriptor.MODE_WRITE_ONLY
|
|
|
+ | ParcelFileDescriptor.MODE_CREATE
|
|
|
+ | ParcelFileDescriptor.MODE_APPEND;
|
|
|
+ } else if ("rw".equals(mode)) {
|
|
|
+ modeBits = ParcelFileDescriptor.MODE_READ_WRITE
|
|
|
+ | ParcelFileDescriptor.MODE_CREATE;
|
|
|
+ } else if ("rwt".equals(mode)) {
|
|
|
+ modeBits = ParcelFileDescriptor.MODE_READ_WRITE
|
|
|
+ | ParcelFileDescriptor.MODE_CREATE
|
|
|
+ | ParcelFileDescriptor.MODE_TRUNCATE;
|
|
|
+ } else {
|
|
|
+ throw new IllegalArgumentException("Invalid mode: " + mode);
|
|
|
+ }
|
|
|
+ return modeBits;
|
|
|
+ }
|
|
|
+
|
|
|
+ private static File buildPath(File base, String... segments) {
|
|
|
+ File cur = base;
|
|
|
+ for (String segment : segments) {
|
|
|
+ if (segment != null) {
|
|
|
+ cur = new File(cur, segment);
|
|
|
+ }
|
|
|
+ }
|
|
|
+ return cur;
|
|
|
+ }
|
|
|
+
|
|
|
+ private static String[] copyOf(String[] original, int newLength) {
|
|
|
+ final String[] result = new String[newLength];
|
|
|
+ System.arraycopy(original, 0, result, 0, newLength);
|
|
|
+ return result;
|
|
|
+ }
|
|
|
+
|
|
|
+ private static Object[] copyOf(Object[] original, int newLength) {
|
|
|
+ final Object[] result = new Object[newLength];
|
|
|
+ System.arraycopy(original, 0, result, 0, newLength);
|
|
|
+ return result;
|
|
|
+ }
|
|
|
+}
|