1 /* 2 * Copyright (C) 2008 Apple Inc. All Rights Reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 * 25 */ 26 27 #ifndef ActiveDOMObject_h 28 #define ActiveDOMObject_h 29 30 #include "core/dom/ContextLifecycleObserver.h" 31 #include "wtf/Assertions.h" 32 33 namespace blink { 34 35 class ActiveDOMObject : public ContextLifecycleObserver { 36 public: 37 ActiveDOMObject(ExecutionContext*); 38 39 // suspendIfNeeded() should be called exactly once after object construction to synchronize 40 // the suspend state with that in ExecutionContext. 41 void suspendIfNeeded(); 42 #if ENABLE(ASSERT) 43 bool suspendIfNeededCalled() const { return m_suspendIfNeededCalled; } 44 #endif 45 46 // Should return true if there's any pending asynchronous activity, and so 47 // this object must not be garbage collected. 48 virtual bool hasPendingActivity() const; 49 50 // These methods have an empty default implementation so that subclasses 51 // which don't need special treatment can skip implementation. 52 virtual void suspend(); 53 virtual void resume(); 54 virtual void stop(); 55 56 void didMoveToNewExecutionContext(ExecutionContext*); 57 58 protected: 59 virtual ~ActiveDOMObject(); 60 61 private: 62 #if ENABLE(ASSERT) 63 bool m_suspendIfNeededCalled; 64 #endif 65 }; 66 67 } // namespace blink 68 69 #endif // ActiveDOMObject_h 70