CLucene - a full-featured, c++ search engine
API Documentation

---

Lock.h

Go to the documentation of this file.

/*------------------------------------------------------------------------------
* Copyright (C) 2003-2006 Ben van Klinken and the CLucene Team
* 
* Distributable under the terms of either the Apache License (Version 2.0) or 
* the GNU Lesser General Public License, as specified in the COPYING file.
------------------------------------------------------------------------------*/
#ifndef _lucene_store_Lock_
#define _lucene_store_Lock_

#if defined(_LUCENE_PRAGMA_ONCE)
# pragma once
#endif

CL_NS_DEF(store)
  class LuceneLock: LUCENE_BASE{
  public:
      LUCENE_STATIC_CONSTANT(int64_t, LOCK_POLL_INTERVAL = 1000);

      virtual bool obtain() = 0;

      bool obtain(int64_t lockWaitTimeout);

      // Release exclusive access.
      virtual void release() = 0;

      virtual bool isLocked() = 0;

      virtual ~LuceneLock()
      {
      }
      
      virtual TCHAR* toString() = 0;
  };


  // Utility class for executing code with exclusive access.
  template<typename T>
  class LuceneLockWith {
  private:
    LuceneLock* lock;
    int64_t lockWaitTimeout;

  protected:
    // Code to execute with exclusive access.
    virtual T doBody() = 0;

  // Constructs an executor that will grab the named lock.
  public:   
    LuceneLockWith(LuceneLock* lock, int64_t lockWaitTimeout) {
      this->lock = lock;
      this->lockWaitTimeout = lockWaitTimeout;
    }
    virtual ~LuceneLockWith(){
        } 

    T runAndReturn() {
        bool locked = false;
        T ret = NULL;
        try {
            locked = lock->obtain(lockWaitTimeout);
            ret = doBody();
        }_CLFINALLY(
            if (locked) 
                lock->release();
        );
                return ret;
    }

        void run() {
        bool locked = false;
        try {
            locked = lock->obtain(lockWaitTimeout);
            doBody();
        }_CLFINALLY(
            if (locked) 
                lock->release();
        );
    }
  };

CL_NS_END
#endif

---

clucene.sourceforge.net