75 lines
2.4 KiB
Java
Executable File
75 lines
2.4 KiB
Java
Executable File
// Copyright 2013 The Chromium Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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package org.chromium.base;
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import android.content.ContentResolver;
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import android.content.Context;
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import android.net.Uri;
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import android.os.ParcelFileDescriptor;
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import android.util.Log;
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/**
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* This class provides methods to access content URI schemes.
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*/
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abstract class ContentUriUtils {
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private static final String TAG = "ContentUriUtils";
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// Prevent instantiation.
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private ContentUriUtils() {}
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/**
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* Opens the content URI for reading, and returns the file descriptor to
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* the caller. The caller is responsible for closing the file desciptor.
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*
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* @param context {@link Context} in interest
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* @param uriString the content URI to open
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* @returns file desciptor upon sucess, or -1 otherwise.
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*/
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@CalledByNative
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public static int openContentUriForRead(Context context, String uriString) {
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ParcelFileDescriptor pfd = getParcelFileDescriptor(context, uriString);
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if (pfd != null) {
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return pfd.detachFd();
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}
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return -1;
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}
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/**
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* Check whether a content URI exists.
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*
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* @param context {@link Context} in interest.
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* @param uriString the content URI to query.
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* @returns true if the uri exists, or false otherwise.
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*/
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@CalledByNative
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public static boolean contentUriExists(Context context, String uriString) {
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ParcelFileDescriptor pfd = getParcelFileDescriptor(context, uriString);
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if (pfd == null) {
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return false;
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}
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return true;
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}
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/**
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* Helper method to open a content URI and return the ParcelFileDescriptor.
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*
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* @param context {@link Context} in interest.
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* @param uriString the content URI to open.
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* @returns ParcelFileDescriptor of the content URI, or NULL if the file does not exist.
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*/
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private static ParcelFileDescriptor getParcelFileDescriptor(Context context, String uriString) {
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ContentResolver resolver = context.getContentResolver();
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Uri uri = Uri.parse(uriString);
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ParcelFileDescriptor pfd = null;
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try {
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pfd = resolver.openFileDescriptor(uri, "r");
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} catch (java.io.FileNotFoundException e) {
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Log.w(TAG, "Cannot find content uri: " + uriString, e);
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}
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return pfd;
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}
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}
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