Merge "SoundTrigger Event logging" into qt-dev

services/voiceinteraction/java/com/android/server/soundtrigger/SoundTriggerLogger.java

+/*
+ * 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.server.soundtrigger;
+
+import android.util.Log;
+
+import java.io.PrintWriter;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.LinkedList;
+
+/**
+* Constructor SoundTriggerLogger class
+*/
+public class SoundTriggerLogger {
+
+    // ring buffer of events to log.
+    private final LinkedList<Event> mEvents;
+
+    private final String mTitle;
+
+    // the maximum number of events to keep in log
+    private final int mMemSize;
+
+    /**
+     * Constructor for Event class.
+     */
+    public abstract static class Event {
+        // formatter for timestamps
+        private static final SimpleDateFormat sFormat = new SimpleDateFormat("MM-dd HH:mm:ss:SSS");
+
+        private final long mTimestamp;
+
+        Event() {
+            mTimestamp = System.currentTimeMillis();
+        }
+
+    /**
+     * Convert event to String
+     * @return StringBuilder
+     */
+        public String toString() {
+            return (new StringBuilder(sFormat.format(new Date(mTimestamp))))
+                    .append(" ").append(eventToString()).toString();
+        }
+
+        /**
+         * Causes the string message for the event to appear in the logcat.
+         * Here is an example of how to create a new event (a StringEvent), adding it to the logger
+         * (an instance of SoundTriggerLogger) while also making it show in the logcat:
+         * <pre>
+         *     myLogger.log(
+         *         (new StringEvent("something for logcat and logger")).printLog(MyClass.TAG) );
+         * </pre>
+         * @param tag the tag for the android.util.Log.v
+         * @return the same instance of the event
+         */
+        public Event printLog(String tag) {
+            Log.i(tag, eventToString());
+            return this;
+        }
+
+        /**
+         * Convert event to String.
+         * This method is only called when the logger history is about to the dumped,
+         * so this method is where expensive String conversions should be made, not when the Event
+         * subclass is created.
+         * Timestamp information will be automatically added, do not include it.
+         * @return a string representation of the event that occurred.
+         */
+        public abstract String eventToString();
+    }
+
+    /**
+    * Constructor StringEvent class
+    */
+    public static class StringEvent extends Event {
+        private final String mMsg;
+
+        public StringEvent(String msg) {
+            mMsg = msg;
+        }
+
+        @Override
+        public String eventToString() {
+            return mMsg;
+        }
+    }
+
+    /**
+     * Constructor for logger.
+     * @param size the maximum number of events to keep in log
+     * @param title the string displayed before the recorded log
+     */
+    public SoundTriggerLogger(int size, String title) {
+        mEvents = new LinkedList<Event>();
+        mMemSize = size;
+        mTitle = title;
+    }
+
+    /**
+     * Constructor for logger.
+     * @param evt the maximum number of events to keep in log
+     */
+    public synchronized void log(Event evt) {
+        if (mEvents.size() >= mMemSize) {
+            mEvents.removeFirst();
+        }
+        mEvents.add(evt);
+    }
+
+    /**
+     * Constructor for logger.
+     * @param pw the maximum number of events to keep in log
+     */
+    public synchronized void dump(PrintWriter pw) {
+        pw.println("ST Event log: " + mTitle);
+        for (Event evt : mEvents) {
+            pw.println(evt.toString());
+        }
+    }
+}