/*
* Copyright (c) 2017, 2019, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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/**
* This package contains classes for consuming Flight Recorder data.
* <p>
* In the following example, the program prints a histogram of all method samples in a recording.
* <pre>
* <code>
* public static void main(String[] args) {
* if (args.length != 0) {
* System.out.println("Must specify recording file.");
* return;
* }
* try (RecordingFile f = new RecordingFile(Paths.get(args[0]))) {
* Map{@literal <}String, SimpleEntry{@literal <}String, Integer{@literal >}{@literal >} histogram = new HashMap{@literal <}{@literal >}();
* int total = 0;
* while (f.hasMoreEvents()) {
* RecordedEvent event = f.readEvent();
* if (event.getEventType().getName().equals("jdk.ExecutionSample")) {
* RecordedStackTrace s = event.getStackTrace();
* if (s != null) {
* RecordedFrame topFrame= s.getFrames().get(0);
* if (topFrame.isJavaFrame()) {
* RecordedMethod method = topFrame.getMethod();
* String methodName = method.getType().getName() + "#" + method.getName() + " " + method.getDescriptor();
* Entry entry = histogram.computeIfAbsent(methodName, u -{@literal >} new SimpleEntry{@literal <}String, Integer{@literal >}(methodName, 0));
* entry.setValue(entry.getValue() + 1);
* total++;
* List{@literal <}SimpleEntry{@literal <}String, Integer{@literal >}{@literal >} entries = new ArrayList{@literal <}{@literal >}(histogram.values());
* entries.sort((u, v) -{@literal >} v.getValue().compareTo(u.getValue()));
* for (SimpleEntry{@literal <}String, Integer{@literal >} c : entries) {
* System.out.printf("%2.0f%% %s\n", 100 * (float) c.getValue() / total, c.getKey());
* System.out.println("\nSample count: " + total);
* } catch (IOException ioe) {
* System.out.println("Error reading file " + args[0] + ". " + ioe.getMessage());
* </code>
* </pre>
* <b>Null-handling</b>
* All methods define whether they accept or return {@code null} in the Javadoc.
* Typically this is expressed as {@code "not null"}. If a {@code null}
* parameter is used where it is not allowed, a
* {@code java.lang.NullPointerException} is thrown. If a {@code null}
* parameters is passed to a method that throws other exceptions, such as
* {@code java.io.IOException}, the {@code java.lang.NullPointerException} takes
* precedence, unless the Javadoc for the method explicitly states how
* {@code null} is handled, i.e. by throwing {@code java.lang.IllegalArgumentException}.
* @since 8
package jdk.jfr.consumer;