jdk/test/jdk/jdk/jfr/jvm/TestGetEventWriterPackage.java
2024-05-30 13:32:57 +00:00

78 lines
3.5 KiB
Java

/*
* Copyright (c) 2022, 2024, 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.
*
* 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.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package jdk.jfr.jvm;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import jdk.jfr.Event;
import jdk.jfr.FlightRecorder;
import jdk.jfr.Recording;
import jdk.jfr.Registered;
/**
* @test Tests that a module can't execute code in jdk.jfr.internal.event unless an event has been registered.
* @key jfr
* @requires vm.hasJFR
* @library /test/lib
* @run main/othervm
* --add-opens jdk.jfr/jdk.jfr.events=ALL-UNNAMED
* jdk.jfr.jvm.TestGetEventWriterPackage
*/
public class TestGetEventWriterPackage {
@Registered(false)
static class PackageUnlockEvent extends Event {
}
public static void main(String... args) throws Throwable {
// --add-opens jdk.jfr/jdk.jfr.events=ALL-UNNAMED gives access to
// the FileReadEvent class in the jdk.jfr module.
// When JFR is initialized the DirectBufferStatisticsEvent is registered and an EventConfiguration object
// assigned to its static field eventConfiguration
try (Recording r = new Recording()) {
r.start();
}
// The tests gets the EventConfiguration object from the class
Class<?>c = Class.forName("jdk.jfr.events.DirectBufferStatisticsEvent");
Field f = c.getDeclaredField("eventConfiguration");
f.setAccessible(true);
Object o = f.get(null);
Class<?> clazz = Class.forName("jdk.jfr.internal.event.EventConfiguration");
Method m = clazz.getDeclaredMethod("isRegistered", new Class[0]);
// it then tries to execute a method on the object from the unnamed module
try {
System.out.println("Is registered: " + m.invoke(o, new Object[0]));
throw new Exception("Did NOT expect unnamed module to be able to execute method in EventConfiguration object before event registration");
} catch (IllegalAccessException iae) {
// OK, as expected
}
// The registration makes the jdk.jfr.internal.event accessible
FlightRecorder.register(PackageUnlockEvent.class);
try {
System.out.println("Is registered: " + m.invoke(o, new Object[0]));
} catch (IllegalAccessException iae) {
throw new Exception("Did expect unnamed module to be able to execute method in EventConfiguration object efter event registration", iae);
}
// If a Security Manager would be present, the caller would need
// to have FlightRecorderPermission("registerEvent")
}
}