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/*
* Copyright (C) 2011 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.example.android.apis.content;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import android.content.ContentProvider;
import android.content.ContentValues;
import android.content.ContentProvider.PipeDataWriter;
import android.content.res.AssetFileDescriptor;
import android.database.Cursor;
import android.database.MatrixCursor;
import android.net.Uri;
import android.os.Bundle;
import android.os.ParcelFileDescriptor;
import android.provider.OpenableColumns;
import android.util.Log;
/**
* A very simple content provider that can serve arbitrary asset files from
* our .apk.
*/
public class FileProvider extends ContentProvider
implements PipeDataWriter<InputStream> {
@Override
public boolean onCreate() {
return true;
}
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
String sortOrder) {
// content providers that support open and openAssetFile should support queries for all
// android.provider.OpenableColumns.
int displayNameIndex = -1;
int sizeIndex = -1;
// If projection is null, return all columns.
if (projection == null) {
projection = new String[] {
OpenableColumns.DISPLAY_NAME,
OpenableColumns.SIZE};
}
for (int i = 0; i < projection.length; i++) {
if (OpenableColumns.DISPLAY_NAME.equals(projection[i])) {
displayNameIndex = i;
}
if (OpenableColumns.SIZE.equals(projection[i])) {
sizeIndex = i;
}
}
MatrixCursor cursor = new MatrixCursor(projection);
Object[] result = new Object[projection.length];
for (int i = 0; i < result.length; i++) {
if (i == displayNameIndex) {
result[i] = uri.getPath();
}
if (i == sizeIndex) {
result[i] = null; // Size is unknown, so null, if it was known, it would go here.
}
}
cursor.addRow(result);
return cursor;
}
@Override
public Uri insert(Uri uri, ContentValues values) {
// Don't support inserts.
return null;
}
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
// Don't support deletes.
return 0;
}
@Override
public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
// Don't support updates.
return 0;
}
@Override
public String getType(Uri uri) {
// For this sample, assume all files are .apks.
return "application/vnd.android.package-archive";
}
@Override
public AssetFileDescriptor openAssetFile(Uri uri, String mode) throws FileNotFoundException {
// Try to open an asset with the given name.
try {
InputStream is = getContext().getAssets().open(uri.getPath());
// Start a new thread that pipes the stream data back to the caller.
return new AssetFileDescriptor(
openPipeHelper(uri, null, null, is, this), 0,
AssetFileDescriptor.UNKNOWN_LENGTH);
} catch (IOException e) {
FileNotFoundException fnf = new FileNotFoundException("Unable to open " + uri);
throw fnf;
}
}
@Override
public void writeDataToPipe(ParcelFileDescriptor output, Uri uri, String mimeType,
Bundle opts, InputStream args) {
// Transfer data from the asset to the pipe the client is reading.
byte[] buffer = new byte[8192];
int n;
FileOutputStream fout = new FileOutputStream(output.getFileDescriptor());
try {
while ((n=args.read(buffer)) >= 0) {
fout.write(buffer, 0, n);
}
} catch (IOException e) {
Log.i("InstallApk", "Failed transferring", e);
} finally {
try {
args.close();
} catch (IOException e) {
}
try {
fout.close();
} catch (IOException e) {
}
}
}
}
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