Revert^2 "Update the BackgroundThread dependency"

1df0ae18

Change-Id: I64489e569ab77585ab02b01872f64673e574b3ff
Bug: 333092549

packages/CrashRecovery/services/java/com/android/server/PackageWatchdog.java

@@ -38,13 +38,13 @@ import android.text.TextUtils;
 import android.util.ArrayMap;
 import android.util.ArraySet;
 import android.util.AtomicFile;
+import android.util.BackgroundThread;
 import android.util.LongArrayQueue;
 import android.util.Slog;
 import android.util.Xml;
 
 import com.android.internal.annotations.GuardedBy;
 import com.android.internal.annotations.VisibleForTesting;
-import com.android.internal.os.BackgroundThread;
 import com.android.internal.util.IndentingPrintWriter;
 import com.android.internal.util.XmlUtils;
 import com.android.modules.utils.TypedXmlPullParser;

packages/CrashRecovery/services/java/com/android/util/BackgroundThread.java

+/*
+ *  * Copyright (C) 2024 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 android.util;
+
+import android.annotation.NonNull;
+import android.os.Handler;
+import android.os.HandlerThread;
+
+import com.android.internal.annotations.GuardedBy;
+
+import java.util.concurrent.Executor;
+
+/**
+ * Thread for asynchronous event processing. This thread is configured as
+ * {@link android.os.Process#THREAD_PRIORITY_BACKGROUND}, which means fewer CPU
+ * resources will be dedicated to it, and it will "have less chance of impacting
+ * the responsiveness of the user interface."
+ * <p>
+ * This thread is best suited for tasks that the user is not actively waiting
+ * for, or for tasks that the user expects to be executed eventually.
+ *
+ * @see com.android.internal.os.BackgroundThread
+ *
+ * TODO: b/326916057 depend on modules-utils-backgroundthread instead
+ * @hide
+ */
+public final class BackgroundThread extends HandlerThread {
+    private static final Object sLock = new Object();
+
+    @GuardedBy("sLock")
+    private static BackgroundThread sInstance;
+    @GuardedBy("sLock")
+    private static Handler sHandler;
+    @GuardedBy("sLock")
+    private static HandlerExecutor sHandlerExecutor;
+
+    private BackgroundThread() {
+        super(BackgroundThread.class.getName(), android.os.Process.THREAD_PRIORITY_BACKGROUND);
+    }
+
+    @GuardedBy("sLock")
+    private static void ensureThreadLocked() {
+        if (sInstance == null) {
+            sInstance = new BackgroundThread();
+            sInstance.start();
+            sHandler = new Handler(sInstance.getLooper());
+            sHandlerExecutor = new HandlerExecutor(sHandler);
+        }
+    }
+
+    /**
+     * Get the singleton instance of this class.
+     *
+     * @return the singleton instance of this class
+     */
+    @NonNull
+    public static BackgroundThread get() {
+        synchronized (sLock) {
+            ensureThreadLocked();
+            return sInstance;
+        }
+    }
+
+    /**
+     * Get the singleton {@link Handler} for this class.
+     *
+     * @return the singleton {@link Handler} for this class.
+     */
+    @NonNull
+    public static Handler getHandler() {
+        synchronized (sLock) {
+            ensureThreadLocked();
+            return sHandler;
+        }
+    }
+
+    /**
+     * Get the singleton {@link Executor} for this class.
+     *
+     * @return the singleton {@link Executor} for this class.
+     */
+    @NonNull
+    public static Executor getExecutor() {
+        synchronized (sLock) {
+            ensureThreadLocked();
+            return sHandlerExecutor;
+        }
+    }
+}

packages/CrashRecovery/services/java/com/android/util/HandlerExecutor.java

+/*
+ * Copyright (C) 2024 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 android.util;
+
+import android.annotation.NonNull;
+import android.os.Handler;
+
+import java.util.Objects;
+import java.util.concurrent.Executor;
+import java.util.concurrent.RejectedExecutionException;
+
+/**
+ * An adapter {@link Executor} that posts all executed tasks onto the given
+ * {@link Handler}.
+ *
+ * TODO: b/326916057 depend on modules-utils-backgroundthread instead
+ * @hide
+ */
+public class HandlerExecutor implements Executor {
+    private final Handler mHandler;
+
+    public HandlerExecutor(@NonNull Handler handler) {
+        mHandler = Objects.requireNonNull(handler);
+    }
+
+    @Override
+    public void execute(Runnable command) {
+        if (!mHandler.post(command)) {
+            throw new RejectedExecutionException(mHandler + " is shutting down");
+        }
+    }
+}