PoolTracer (DBPool 6.0 API)

java.lang.Object
- snaq.util.PoolTracer<T>

Type Parameters:
T - class type of pooled objects

All Implemented Interfaces:

EventListener, ObjectPoolListener<T>
```
public class PoolTracer<T extends Reusable>
extends Object
implements ObjectPoolListener<T>
```
Class to create a simple trace of pool usage statistics to a log file. The default date format is local time in ISO 8601 compatible format.

Author:

Giles Winstanley

Constructor Summary

Constructors
Constructor and Description
`PoolTracer(ObjectPool<T> pool, File file)` Creates a new `PoolTracer` which logs to the specified file.
`PoolTracer(ObjectPool<T> pool, PrintWriter logWriter, boolean closeOnExit)` Creates a new `PoolTracer` which logs to the specified `PrintWriter`.
`PoolTracer(ObjectPool<T> pool, String filename)` Creates a new ObjectPoolAudit which logs to the specified File.
`PoolTracer(Properties props)` Creates a new `PoolTracer` which logs to the specified file.

Method Summary

Methods
Modifier and Type	Method and Description
`MessageFormat`	`getMessageFormatInstance()` Returns the current `MessageFormat` instance used for formatting log messages.
`protected void`	`logPoolStats(ObjectPoolEvent<T> evt)` Writes an entry containing the pool statistics to the log file.
`void`	`maxPoolLimitExceeded(ObjectPoolEvent<T> evt)` Called when a check-out request causes the poolSize limit to be exceeded.
`void`	`maxPoolLimitReached(ObjectPoolEvent<T> evt)` Called when a check-out request causes the poolSize limit to be reached.
`void`	`maxSizeLimitError(ObjectPoolEvent<T> evt)` Called when a check-out request attempts to exceed the maxSize limit.
`void`	`maxSizeLimitReached(ObjectPoolEvent<T> evt)` Called when a check-out request causes the maxSize limit to be reached.
`void`	`poolCheckIn(ObjectPoolEvent<T> evt)` Called when an item is checked back in to the pool.
`void`	`poolCheckOut(ObjectPoolEvent<T> evt)` Called when an item is checked out of the pool.
`void`	`poolFlushed(ObjectPoolEvent<T> evt)` Called when the pool is flushed of all free/unused items.
`void`	`poolInitCompleted(ObjectPoolEvent<T> evt)` Called when the pool's `ObjectPool.init(int)` method has completed.
`void`	`poolParametersChanged(ObjectPoolEvent<T> evt)` Called when the pool's parameters are changed.
`void`	`poolReleased(ObjectPoolEvent<T> evt)` Called when the pool is released (no more events are fired by the pool after this event).
`void`	`setDateFormat(DateFormat df)` Sets the date formatter for the logging.
`void`	`setMessageFormat(MessageFormat mf)` Sets the `MessageFormat` instance used for formatting log messages.
`void`	`validationError(ObjectPoolEvent<T> evt)` Called when an item is found to be invalid.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - PoolTracer
```
public PoolTracer(ObjectPool<T> pool,
          PrintWriter logWriter,
          boolean closeOnExit)
```
    Creates a new PoolTracer which logs to the specified PrintWriter.
    
    Parameters:
    pool - ObjectPool for which to trace activity
    logWriter - PrintWriter to use for writing trace activity
    closeOnExit - whether to close the PrintWriter on release
  - PoolTracer
```
public PoolTracer(ObjectPool<T> pool,
          File file)
           throws FileNotFoundException
```
    Creates a new PoolTracer which logs to the specified file. Note: if the file already exists it is truncated to zero-length, then used for writing the log.
    
    Parameters:
    pool - ObjectPool for which to trace activity
    file - File to which to log trace activity
    
    Throws:
    
    FileNotFoundException
  - PoolTracer
```
public PoolTracer(ObjectPool<T> pool,
          String filename)
           throws FileNotFoundException
```
    Creates a new ObjectPoolAudit which logs to the specified File.
    
    Parameters:
    pool - ObjectPool for which to trace activity
    filename - name of file to which to log trace activity
    
    Throws:
    
    FileNotFoundException
  - PoolTracer
```
public PoolTracer(Properties props)
           throws FileNotFoundException
```
    Creates a new PoolTracer which logs to the specified file. Note: if the file already exists it is truncated to zero-length, then used for writing the log.
    
    Parameters:
    props - Properties defining trace activity
    
    Throws:
    
    FileNotFoundException
- Method Detail
  - setDateFormat
```
public void setDateFormat(DateFormat df)
```
    Sets the date formatter for the logging. The default is the same as used by the LogUtil class.
    
    Parameters:
    df - DateFormat instance to use for formatting log messages
  - setMessageFormat
```
public final void setMessageFormat(MessageFormat mf)
```
    Sets the MessageFormat instance used for formatting log messages. To use the default instance, just call this method with a null argument.
    Format strings are specified using the following variables:
    - {0} - pool name (string)
    - {1} - minpool (integer)
    - {2} - maxpool (integer)
    - {3} - maxsize (integer)
    - {4} - idle timeout (long)
    - {5} - items checked out (integer)
    - {6} - free item count (integer)
    - {7} - current pool size (i.e. {5}+{6}, integer)
    - {8} - hit rate (float)
    - {9} - event type (string)
    The default format is as follows:
```
 {0}: minpool={1,number,#}, maxpool={2,number,#}, maxsize={3,number,#}, idleTimeout={4,number,#}, out={5,number,#}, free={6,number,#}, hitRate={8,number,0.0##%}
 
```
    Parameters:
    mf - MessageFormat instance to use for formatting log messages
  - getMessageFormatInstance
```
public MessageFormat getMessageFormatInstance()
```
    Returns the current MessageFormat instance used for formatting log messages.
    
    Returns:
    The current MessageFormat instance used for formatting log messages
  - logPoolStats
```
protected void logPoolStats(ObjectPoolEvent<T> evt)
```
    Writes an entry containing the pool statistics to the log file.
    
    Parameters:
    evt - event instance to log
  - poolInitCompleted
```
public void poolInitCompleted(ObjectPoolEvent<T> evt)
```
    Description copied from interface: ObjectPoolListener
    
    Called when the pool's ObjectPool.init(int) method has completed.
    
    Specified by:
    
    poolInitCompleted in interface ObjectPoolListener<T extends Reusable>
    
    Parameters:
    evt - event instance
  - validationError
```
public void validationError(ObjectPoolEvent<T> evt)
```
    Description copied from interface: ObjectPoolListener
    
    Called when an item is found to be invalid.
    
    Specified by:
    
    validationError in interface ObjectPoolListener<T extends Reusable>
    
    Parameters:
    evt - event instance
  - maxPoolLimitReached
```
public void maxPoolLimitReached(ObjectPoolEvent<T> evt)
```
    Description copied from interface: ObjectPoolListener
    
    Called when a check-out request causes the poolSize limit to be reached.
    
    Specified by:
    
    maxPoolLimitReached in interface ObjectPoolListener<T extends Reusable>
    
    Parameters:
    evt - event instance
  - maxPoolLimitExceeded
```
public void maxPoolLimitExceeded(ObjectPoolEvent<T> evt)
```
    Description copied from interface: ObjectPoolListener
    
    Called when a check-out request causes the poolSize limit to be exceeded.
    
    Specified by:
    
    maxPoolLimitExceeded in interface ObjectPoolListener<T extends Reusable>
    
    Parameters:
    evt - event instance
  - maxSizeLimitReached
```
public void maxSizeLimitReached(ObjectPoolEvent<T> evt)
```
    Description copied from interface: ObjectPoolListener
    
    Called when a check-out request causes the maxSize limit to be reached.
    
    Specified by:
    
    maxSizeLimitReached in interface ObjectPoolListener<T extends Reusable>
    
    Parameters:
    evt - event instance
  - maxSizeLimitError
```
public void maxSizeLimitError(ObjectPoolEvent<T> evt)
```
    Description copied from interface: ObjectPoolListener
    
    Called when a check-out request attempts to exceed the maxSize limit.
    
    Specified by:
    
    maxSizeLimitError in interface ObjectPoolListener<T extends Reusable>
    
    Parameters:
    evt - event instance
  - poolCheckIn
```
public void poolCheckIn(ObjectPoolEvent<T> evt)
```
    Description copied from interface: ObjectPoolListener
    
    Called when an item is checked back in to the pool.
    
    Specified by:
    
    poolCheckIn in interface ObjectPoolListener<T extends Reusable>
    
    Parameters:
    evt - event instance
  - poolCheckOut
```
public void poolCheckOut(ObjectPoolEvent<T> evt)
```
    Description copied from interface: ObjectPoolListener
    
    Called when an item is checked out of the pool.
    
    Specified by:
    
    poolCheckOut in interface ObjectPoolListener<T extends Reusable>
    
    Parameters:
    evt - event instance
  - poolParametersChanged
```
public void poolParametersChanged(ObjectPoolEvent<T> evt)
```
    Description copied from interface: ObjectPoolListener
    
    Called when the pool's parameters are changed.
    
    Specified by:
    
    poolParametersChanged in interface ObjectPoolListener<T extends Reusable>
    
    Parameters:
    evt - event instance
  - poolFlushed
```
public void poolFlushed(ObjectPoolEvent<T> evt)
```
    Description copied from interface: ObjectPoolListener
    
    Called when the pool is flushed of all free/unused items.
    
    Specified by:
    
    poolFlushed in interface ObjectPoolListener<T extends Reusable>
    
    Parameters:
    evt - event instance
  - poolReleased
```
public void poolReleased(ObjectPoolEvent<T> evt)
```
    Description copied from interface: ObjectPoolListener
    
    Called when the pool is released (no more events are fired by the pool after this event).
    
    Specified by:
    
    poolReleased in interface ObjectPoolListener<T extends Reusable>
    
    Parameters:
    evt - event instance

Class PoolTracer<T extends Reusable>

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

PoolTracer

PoolTracer

PoolTracer

PoolTracer

Method Detail

setDateFormat

setMessageFormat

getMessageFormatInstance

logPoolStats

poolInitCompleted

validationError

maxPoolLimitReached

maxPoolLimitExceeded

maxSizeLimitReached

maxSizeLimitError

poolCheckIn

poolCheckOut

poolParametersChanged

poolFlushed

poolReleased