| /* |
| * Copyright (C) 2014 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.net; |
| |
| import android.os.Handler; |
| import android.os.HandlerThread; |
| import android.text.TextUtils; |
| import android.util.Log; |
| |
| import java.io.BufferedOutputStream; |
| import java.io.DataOutputStream; |
| import java.io.FileOutputStream; |
| import java.io.IOException; |
| |
| public class DelayedDiskWrite { |
| private HandlerThread mDiskWriteHandlerThread; |
| private Handler mDiskWriteHandler; |
| /* Tracks multiple writes on the same thread */ |
| private int mWriteSequence = 0; |
| private final String TAG = "DelayedDiskWrite"; |
| |
| public interface Writer { |
| public void onWriteCalled(DataOutputStream out) throws IOException; |
| } |
| |
| public void write(final String filePath, final Writer w) { |
| write(filePath, w, true); |
| } |
| |
| public void write(final String filePath, final Writer w, final boolean open) { |
| if (TextUtils.isEmpty(filePath)) { |
| throw new IllegalArgumentException("empty file path"); |
| } |
| |
| /* Do a delayed write to disk on a separate handler thread */ |
| synchronized (this) { |
| if (++mWriteSequence == 1) { |
| mDiskWriteHandlerThread = new HandlerThread("DelayedDiskWriteThread"); |
| mDiskWriteHandlerThread.start(); |
| mDiskWriteHandler = new Handler(mDiskWriteHandlerThread.getLooper()); |
| } |
| } |
| |
| mDiskWriteHandler.post(new Runnable() { |
| @Override |
| public void run() { |
| doWrite(filePath, w, open); |
| } |
| }); |
| } |
| |
| private void doWrite(String filePath, Writer w, boolean open) { |
| DataOutputStream out = null; |
| try { |
| if (open) { |
| out = new DataOutputStream(new BufferedOutputStream( |
| new FileOutputStream(filePath))); |
| } |
| w.onWriteCalled(out); |
| } catch (IOException e) { |
| loge("Error writing data file " + filePath); |
| } finally { |
| if (out != null) { |
| try { |
| out.close(); |
| } catch (Exception e) {} |
| } |
| |
| // Quit if no more writes sent |
| synchronized (this) { |
| if (--mWriteSequence == 0) { |
| mDiskWriteHandler.getLooper().quit(); |
| mDiskWriteHandler = null; |
| mDiskWriteHandlerThread = null; |
| } |
| } |
| } |
| } |
| |
| private void loge(String s) { |
| Log.e(TAG, s); |
| } |
| } |
| |