1 /*
   2  * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 package jdk.vm.ci.hotspot.services;
  24 
  25 import jdk.vm.ci.code.CompiledCode;
  26 import jdk.vm.ci.code.InstalledCode;
  27 import jdk.vm.ci.hotspot.HotSpotCodeCacheProvider;
  28 import jdk.vm.ci.hotspot.HotSpotJVMCIRuntime;
  29 import jdk.vm.ci.meta.JVMCIMetaAccessContext;
  30 import jdk.vm.ci.meta.ResolvedJavaType;
  31 import jdk.vm.ci.services.JVMCIPermission;
  32 
  33 /**
  34  * Service-provider class for responding to VM events and for creating
  35  * {@link JVMCIMetaAccessContext}s.
  36  */
  37 public abstract class HotSpotVMEventListener {
  38 
  39     private static Void checkPermission() {
  40         SecurityManager sm = System.getSecurityManager();
  41         if (sm != null) {
  42             sm.checkPermission(new JVMCIPermission());
  43         }
  44         return null;
  45     }
  46 
  47     @SuppressWarnings("unused")
  48     HotSpotVMEventListener(Void ignore) {
  49     }
  50 
  51     /**
  52      * Initializes a new instance of this class.
  53      *
  54      * @throws SecurityException if a security manager has been installed and it denies
  55      *             {@link JVMCIPermission}
  56      */
  57     protected HotSpotVMEventListener() {
  58         this(checkPermission());
  59     }
  60 
  61     /**
  62      * Notifies this client that the VM is shutting down.
  63      */
  64     public void notifyShutdown() {
  65     }
  66 
  67     /**
  68      * Notify on successful install into the code cache.
  69      *
  70      * @param hotSpotCodeCacheProvider
  71      * @param installedCode
  72      * @param compiledCode
  73      */
  74     public void notifyInstall(HotSpotCodeCacheProvider hotSpotCodeCacheProvider, InstalledCode installedCode, CompiledCode compiledCode) {
  75     }
  76 
  77     /**
  78      * Notify on completion of a bootstrap.
  79      */
  80     public void notifyBootstrapFinished() {
  81     }
  82 
  83     /**
  84      * Create a custom {@link JVMCIMetaAccessContext} to be used for managing the lifetime of loaded
  85      * metadata. It a custom one isn't created then the default implementation will be a single
  86      * context with globally shared instances of {@link ResolvedJavaType} that are never released.
  87      *
  88      * @param runtime the runtime instance that will use the returned context
  89      * @return a custom context or null
  90      */
  91     public JVMCIMetaAccessContext createMetaAccessContext(HotSpotJVMCIRuntime runtime) {
  92         return null;
  93     }
  94 }