| /* |
| * Copyright (C) 2019 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.systemui |
| |
| import android.util.Log |
| import androidx.annotation.GuardedBy |
| import com.android.internal.util.Preconditions |
| import java.io.FileDescriptor |
| import java.io.PrintWriter |
| import java.lang.ref.WeakReference |
| import javax.inject.Inject |
| import javax.inject.Singleton |
| |
| // TODO: Move all Dumpable dependencies to use DumpController |
| /** |
| * Controller that allows any [Dumpable] to subscribe and be dumped along with other SystemUI |
| * dependencies. |
| */ |
| @Singleton |
| class DumpController @Inject constructor() : Dumpable { |
| |
| companion object { |
| private const val TAG = "DumpController" |
| private const val DEBUG = false |
| } |
| |
| @GuardedBy("listeners") |
| private val listeners = mutableListOf<WeakReference<Dumpable>>() |
| val numListeners: Int |
| get() = listeners.size |
| |
| /** |
| * Adds a [Dumpable] listener to be dumped. It will only be added if it is not already tracked. |
| * |
| * @param listener the [Dumpable] to be added |
| */ |
| fun addListener(listener: Dumpable) { |
| Preconditions.checkNotNull(listener, "The listener to be added cannot be null") |
| if (DEBUG) Log.v(TAG, "*** register callback for $listener") |
| synchronized<Unit>(listeners) { |
| if (listeners.any { it.get() == listener }) { |
| if (DEBUG) { |
| Log.e(TAG, "Object tried to add another callback") |
| } |
| } else { |
| listeners.add(WeakReference(listener)) |
| } |
| } |
| } |
| |
| /** |
| * Removes a listener from the list of elements to be dumped. |
| * |
| * @param listener the [Dumpable] to be removed. |
| */ |
| fun removeListener(listener: Dumpable) { |
| if (DEBUG) Log.v(TAG, "*** unregister callback for $listener") |
| synchronized(listeners) { |
| listeners.removeAll { it.get() == listener || it.get() == null } |
| } |
| } |
| |
| /** |
| * Dump all the [Dumpable] registered with the controller |
| */ |
| override fun dump(fd: FileDescriptor?, pw: PrintWriter, args: Array<String>?) { |
| pw.println("DumpController state:") |
| synchronized(listeners) { |
| listeners.forEach { it.get()?.dump(fd, pw, args) } |
| } |
| } |
| } |