| /* |
| * Copyright (C) 2006 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.UnsupportedAppUsage; |
| import android.os.SystemClock; |
| |
| import java.io.FileDescriptor; |
| import java.io.PrintWriter; |
| import java.time.Instant; |
| import java.time.LocalDateTime; |
| import java.util.ArrayDeque; |
| import java.util.Deque; |
| import java.util.Iterator; |
| |
| /** |
| * @hide |
| */ |
| public final class LocalLog { |
| |
| private final Deque<String> mLog; |
| private final int mMaxLines; |
| |
| /** |
| * {@code true} to use log timestamps expressed in local date/time, {@code false} to use log |
| * timestamped expressed with the elapsed realtime clock and UTC system clock. {@code false} is |
| * useful when logging behavior that modifies device time zone or system clock. |
| */ |
| private final boolean mUseLocalTimestamps; |
| |
| @UnsupportedAppUsage |
| public LocalLog(int maxLines) { |
| this(maxLines, true /* useLocalTimestamps */); |
| } |
| |
| public LocalLog(int maxLines, boolean useLocalTimestamps) { |
| mMaxLines = Math.max(0, maxLines); |
| mLog = new ArrayDeque<>(mMaxLines); |
| mUseLocalTimestamps = useLocalTimestamps; |
| } |
| |
| @UnsupportedAppUsage |
| public void log(String msg) { |
| if (mMaxLines <= 0) { |
| return; |
| } |
| final String logLine; |
| if (mUseLocalTimestamps) { |
| logLine = String.format("%s - %s", LocalDateTime.now(), msg); |
| } else { |
| logLine = String.format( |
| "%s / %s - %s", SystemClock.elapsedRealtime(), Instant.now(), msg); |
| } |
| append(logLine); |
| } |
| |
| private synchronized void append(String logLine) { |
| while (mLog.size() >= mMaxLines) { |
| mLog.remove(); |
| } |
| mLog.add(logLine); |
| } |
| |
| @UnsupportedAppUsage |
| public synchronized void dump(FileDescriptor fd, PrintWriter pw, String[] args) { |
| dump(pw); |
| } |
| |
| public synchronized void dump(PrintWriter pw) { |
| Iterator<String> itr = mLog.iterator(); |
| while (itr.hasNext()) { |
| pw.println(itr.next()); |
| } |
| } |
| |
| public synchronized void reverseDump(FileDescriptor fd, PrintWriter pw, String[] args) { |
| reverseDump(pw); |
| } |
| |
| public synchronized void reverseDump(PrintWriter pw) { |
| Iterator<String> itr = mLog.descendingIterator(); |
| while (itr.hasNext()) { |
| pw.println(itr.next()); |
| } |
| } |
| |
| public static class ReadOnlyLocalLog { |
| private final LocalLog mLog; |
| ReadOnlyLocalLog(LocalLog log) { |
| mLog = log; |
| } |
| @UnsupportedAppUsage |
| public void dump(FileDescriptor fd, PrintWriter pw, String[] args) { |
| mLog.dump(pw); |
| } |
| public void dump(PrintWriter pw) { |
| mLog.dump(pw); |
| } |
| public void reverseDump(FileDescriptor fd, PrintWriter pw, String[] args) { |
| mLog.reverseDump(pw); |
| } |
| public void reverseDump(PrintWriter pw) { |
| mLog.reverseDump(pw); |
| } |
| } |
| |
| @UnsupportedAppUsage |
| public ReadOnlyLocalLog readOnlyLocalLog() { |
| return new ReadOnlyLocalLog(this); |
| } |
| } |