[Jrobin-commits] src/org/jrobin/core RrdDbPool.java,1.3,1.4

[<sa...@us...>]

Update of /cvsroot/jrobin/src/org/jrobin/core
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv20110/org/jrobin/core

Modified Files:
	RrdDbPool.java 
Log Message:
Improved RrdDbPool, removed bug in Grapher (RRD files were never closed or returned to the pool)

Index: RrdDbPool.java
===================================================================
RCS file: /cvsroot/jrobin/src/org/jrobin/core/RrdDbPool.java,v
retrieving revision 1.3
retrieving revision 1.4
diff -C2 -d -r1.3 -r1.4
*** RrdDbPool.java	12 Nov 2003 10:22:09 -0000	1.3
--- RrdDbPool.java	1 Mar 2004 12:02:46 -0000	1.4
***************
*** 90,95 ****
   * threads and many simultaneously open RRD files.<p>
   *
!  * The pool is thread-safe.
   *
   */
  public class RrdDbPool {
--- 90,99 ----
   * threads and many simultaneously open RRD files.<p>
   *
!  * RrdDbPool can be forced to block (force wait on) all threads requesting access
!  * to a single RRD file which is already in use (not yet returned to the pool).
!  * If you want such feature, call
!  * {@link #setExclusiveMode setExclusiveMode()} method with a <code>true</code> argument.<p>
   *
+  * The pool is thread-safe.<p>
   */
  public class RrdDbPool {
***************
*** 103,106 ****
--- 107,112 ----
  	private static int capacity = INITIAL_CAPACITY;
  
+ 	private boolean exclusiveMode = false;
+ 
  	private HashMap rrdMap = new HashMap();
  
***************
*** 131,146 ****
  	public synchronized RrdDb requestRrdDb(String path) throws IOException, RrdException {
  		String keypath = getCanonicalPath(path);
! 		if(rrdMap.containsKey(keypath)) {
! 			// already open
! 			RrdEntry rrdEntry = (RrdEntry) rrdMap.get(keypath);
! 			rrdEntry.reportUsage();
! 			debug("EXISTING: " + rrdEntry.dump());
! 			return rrdEntry.getRrdDb();
! 		}
! 		else {
! 			// not found, open it
! 			RrdDb rrdDb = new RrdDb(path);
! 			put(keypath, rrdDb);
! 			return rrdDb;
  		}
  	}
--- 137,162 ----
  	public synchronized RrdDb requestRrdDb(String path) throws IOException, RrdException {
  		String keypath = getCanonicalPath(path);
! 		for (;;) { // ugly, but it works
! 			if (rrdMap.containsKey(keypath)) {
! 				// already open
! 				RrdEntry rrdEntry = (RrdEntry) rrdMap.get(keypath);
! 				if(exclusiveMode && rrdEntry.getUsageCount() > 0) {
! 					// reference already in use, wait until the reference
! 					// is returned to the pool
! 					try {
! 						wait();
! 					} catch (InterruptedException e) { }
! 					// try to obtain the same reference once again
! 					continue;
! 				}
! 				rrdEntry.reportUsage();
! 				debug("EXISTING: " + rrdEntry.dump());
! 				return rrdEntry.getRrdDb();
! 			} else {
! 				// not found, open it
! 				RrdDb rrdDb = new RrdDb(path);
! 				put(keypath, rrdDb);
! 				return rrdDb;
! 			}
  		}
  	}
***************
*** 230,237 ****
  			RrdEntry rrdEntry = (RrdEntry) rrdMap.get(keypath);
  			rrdEntry.release();
  			debug("RELEASED: " + rrdEntry.dump());
  		}
  		else {
! 			throw new RrdException("RrdDb with path " + keypath + " not in pool");
  		}
  		gc();
--- 246,256 ----
  			RrdEntry rrdEntry = (RrdEntry) rrdMap.get(keypath);
  			rrdEntry.release();
+ 			if(exclusiveMode) {
+ 				notifyAll();
+ 			}
  			debug("RELEASED: " + rrdEntry.dump());
  		}
  		else {
! 			throw new RrdException("RrdDb with path " + keypath + " not in the pool");
  		}
  		gc();
***************
*** 342,345 ****
--- 361,385 ----
  	}
  
+ 	/**
+ 	 * Checks if RrdDbPool will return a reference to an already open RRD file if it is still
+ 	 * in use (not released, not returned to the pool). If true, simultaneous access
+ 	 * to the same RRD file will not be possible.
+ 	 * @return Current working mode of RrdDbPool (initial working mode is <code>false</code>)
+ 	 */
+ 	public boolean isExclusiveMode() {
+ 		return exclusiveMode;
+ 	}
+ 
+ 	/**
+ 	 * Method used to set the current working mode of RrdDbPool. If set to true, simultaneous
+ 	 * access to the same RRD file will not be possible. In case of several threads requesting
+ 	 * a reference to the same RRD file, one thread will get the reference, other threads will
+ 	 * block until the reference is returned to the pool.
+ 	 * @param exclusiveMode Working mode of RrdDbPool
+ 	 */
+ 	public void setExclusiveMode(boolean exclusiveMode) {
+ 		this.exclusiveMode = exclusiveMode;
+ 	}
+ 
  	private class RrdEntry {
  		private RrdDb rrdDb;