| 1 | /* |
| 2 | * SPDX-License-Identifier: LGPL-2.1-only |
| 3 | * |
| 4 | * Copyright (C) 2015 EfficiOS Inc. |
| 5 | * Copyright (C) 2015 Alexandre Montplaisir <alexmonthy@efficios.com> |
| 6 | * Copyright (C) 2013 David Goulet <dgoulet@efficios.com> |
| 7 | */ |
| 8 | |
| 9 | package org.lttng.ust.agent.jul; |
| 10 | |
| 11 | import java.io.IOException; |
| 12 | import java.util.Collection; |
| 13 | import java.util.Map; |
| 14 | import java.util.Map.Entry; |
| 15 | import java.util.concurrent.atomic.AtomicLong; |
| 16 | import java.util.logging.Formatter; |
| 17 | import java.util.logging.Handler; |
| 18 | import java.util.logging.LogRecord; |
| 19 | |
| 20 | import org.lttng.ust.agent.ILttngAgent; |
| 21 | import org.lttng.ust.agent.ILttngHandler; |
| 22 | import org.lttng.ust.agent.context.ContextInfoSerializer; |
| 23 | |
| 24 | /** |
| 25 | * LTTng-UST JUL log handler. |
| 26 | * |
| 27 | * Applications can attach this handler to their |
| 28 | * {@link java.util.logging.Logger} to have it generate UST events from logging |
| 29 | * events received through the logger. |
| 30 | * |
| 31 | * It sends its events to UST via the JNI library "liblttng-ust-jul-jni.so". |
| 32 | * Make sure this library is available before using this handler. |
| 33 | * |
| 34 | * @author Alexandre Montplaisir |
| 35 | * @author David Goulet |
| 36 | */ |
| 37 | public class LttngLogHandler extends Handler implements ILttngHandler { |
| 38 | |
| 39 | private static final String SHARED_OBJECT_NAME = "lttng-ust-jul-jni"; |
| 40 | |
| 41 | /** |
| 42 | * Dummy Formatter object, so we can use its |
| 43 | * {@link Formatter#formatMessage(LogRecord)} method. |
| 44 | */ |
| 45 | private static final Formatter FORMATTER = new Formatter() { |
| 46 | @Override |
| 47 | public String format(LogRecord record) { |
| 48 | throw new UnsupportedOperationException(); |
| 49 | } |
| 50 | }; |
| 51 | |
| 52 | private final ILttngAgent<LttngLogHandler> agent; |
| 53 | |
| 54 | /** Number of events logged (really sent through JNI) by this handler */ |
| 55 | private final AtomicLong eventCount = new AtomicLong(0); |
| 56 | |
| 57 | /** |
| 58 | * Constructor |
| 59 | * |
| 60 | * @throws IOException |
| 61 | * This handler requires the lttng-ust-jul-jni.so native |
| 62 | * library, through which it will send the trace events. This |
| 63 | * exception is throw is this library cannot be found. |
| 64 | * @throws SecurityException |
| 65 | * We will forward any SecurityExcepion that may be thrown when |
| 66 | * trying to load the JNI library. |
| 67 | */ |
| 68 | public LttngLogHandler() throws IOException, SecurityException { |
| 69 | super(); |
| 70 | /* Initialize LTTng UST tracer. */ |
| 71 | try { |
| 72 | System.loadLibrary(SHARED_OBJECT_NAME); //$NON-NLS-1$ |
| 73 | } catch (UnsatisfiedLinkError e) { |
| 74 | throw new IOException(e); |
| 75 | } |
| 76 | |
| 77 | /** Register to the relevant agent */ |
| 78 | agent = LttngJulAgent.getInstance(); |
| 79 | agent.registerHandler(this); |
| 80 | } |
| 81 | |
| 82 | @Override |
| 83 | public synchronized void close() { |
| 84 | agent.unregisterHandler(this); |
| 85 | } |
| 86 | |
| 87 | /** |
| 88 | * Get the number of events logged by this handler so far. This means the |
| 89 | * number of events actually sent through JNI to UST. |
| 90 | * |
| 91 | * @return The number of events logged so far |
| 92 | */ |
| 93 | @Override |
| 94 | public long getEventCount() { |
| 95 | return eventCount.get(); |
| 96 | } |
| 97 | |
| 98 | @Override |
| 99 | public void flush() { |
| 100 | } |
| 101 | |
| 102 | @Override |
| 103 | public void publish(LogRecord record) { |
| 104 | /* |
| 105 | * Check if the current message should be logged, according to the UST |
| 106 | * session settings. |
| 107 | */ |
| 108 | if (!agent.isEventEnabled(record.getLoggerName())) { |
| 109 | return; |
| 110 | } |
| 111 | |
| 112 | String formattedMessage = FORMATTER.formatMessage(record); |
| 113 | |
| 114 | /* Retrieve all the requested context information we can find */ |
| 115 | Collection<Entry<String, Map<String, Integer>>> enabledContexts = agent.getEnabledAppContexts(); |
| 116 | ContextInfoSerializer.SerializedContexts contextInfo = ContextInfoSerializer.queryAndSerializeRequestedContexts(enabledContexts); |
| 117 | |
| 118 | eventCount.incrementAndGet(); |
| 119 | |
| 120 | /* |
| 121 | * Specific tracepoint designed for JUL events. The source class of the |
| 122 | * caller is used for the event name, the raw message is taken, the |
| 123 | * loglevel of the record and the thread ID. |
| 124 | */ |
| 125 | LttngJulApi.tracepointWithContext(formattedMessage, |
| 126 | record.getLoggerName(), |
| 127 | record.getSourceClassName(), |
| 128 | record.getSourceMethodName(), |
| 129 | record.getMillis(), |
| 130 | record.getLevel().intValue(), |
| 131 | record.getThreadID(), |
| 132 | contextInfo.getEntriesArray(), |
| 133 | contextInfo.getStringsArray()); |
| 134 | } |
| 135 | |
| 136 | } |