com.sun.enterprise.resource.pool.ConnectionPool Maven / Gradle / Ivy
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package com.sun.enterprise.resource.pool;
import com.sun.enterprise.connectors.ConnectorConnectionPool;
import com.sun.enterprise.connectors.ConnectorRuntime;
import com.sun.enterprise.connectors.service.ConnectorAdminServiceUtils;
import com.sun.enterprise.resource.ResourceHandle;
import com.sun.enterprise.resource.ResourceSpec;
import com.sun.enterprise.resource.ResourceState;
import com.sun.enterprise.resource.listener.PoolLifeCycleListener;
import com.sun.enterprise.resource.allocator.ResourceAllocator;
import com.sun.enterprise.resource.pool.datastructure.DataStructure;
import com.sun.enterprise.resource.pool.datastructure.DataStructureFactory;
import com.sun.enterprise.resource.pool.resizer.Resizer;
import com.sun.enterprise.resource.pool.waitqueue.PoolWaitQueue;
import com.sun.enterprise.resource.pool.waitqueue.PoolWaitQueueFactory;
import com.sun.enterprise.util.i18n.StringManager;
import com.sun.enterprise.transaction.api.JavaEETransaction;
import com.sun.logging.LogDomains;
import com.sun.appserv.connectors.internal.api.PoolingException;
import javax.naming.Context;
import javax.naming.NamingException;
import javax.resource.ResourceException;
import javax.transaction.Transaction;
import java.util.*;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
* Connection Pool for Connector & JDBC resources
*
* @author Jagadish Ramu
*/
public class ConnectionPool implements ResourcePool, ConnectionLeakListener,
ResourceHandler, PoolProperties {
protected final static StringManager localStrings =
StringManager.getManager(ConnectionPool.class);
protected final static Logger _logger = LogDomains.getLogger(ConnectionPool.class,LogDomains.RSR_LOGGER);
//pool life-cycle config properties
protected int maxPoolSize; // Max size of the pool
protected int steadyPoolSize; // Steady size of the pool
protected int resizeQuantity; // used by resizer to downsize the pool
protected int maxWaitTime; // The total time a thread is willing to wait for a resource object.
protected long idletime; // time (in ms) before destroying a free resource
//pool config properties
protected boolean failAllConnections = false;
protected boolean matchConnections = false;
protected boolean validation = false;
protected boolean preferValidateOverRecreate = false;
// hold on to the resizer task so we can cancel/reschedule it.
protected Resizer resizerTask;
protected volatile boolean poolInitialized = false;
protected Timer timer;
//advanced pool config properties
protected boolean connectionCreationRetry_;
protected int connectionCreationRetryAttempts_;
protected long conCreationRetryInterval_;
protected long validateAtmostPeriodInMilliSeconds_;
protected int maxConnectionUsage_;
//To validate a Sun RA Pool Connection if it hasnot been validated
// in the past x sec. (x=idle-timeout)
//The property will be set from system property -
// com.sun.enterprise.connectors.ValidateAtmostEveryIdleSecs=true
private boolean validateAtmostEveryIdleSecs = false;
protected String resourceSelectionStrategyClass;
protected PoolLifeCycleListener poolLifeCycleListener;
//Gateway used to control the concurrency within the round-trip of resource access.
protected ResourceGateway gateway;
protected String resourceGatewayClass;
protected ConnectionLeakDetector leakDetector;
protected DataStructure ds;
protected String dataStructureType;
protected String dataStructureParameters;
protected PoolWaitQueue waitQueue;
protected String poolWaitQueueClass;
protected final String name; //poolName
private PoolTxHelper poolTxHelper;
// adding resourceSpec and allocator
protected ResourceSpec resourceSpec;
// NOTE: This resource allocator may not be the same as the allocator passed in to getResource()
protected ResourceAllocator allocator;
private boolean selfManaged_;
public ConnectionPool(String poolName) throws PoolingException {
this.name = poolName;
setPoolConfiguration();
initializePoolDataStructure();
initializeResourceSelectionStragegy();
initializePoolWaitQueue();
poolTxHelper = new PoolTxHelper(name);
gateway = ResourceGateway.getInstance(resourceGatewayClass);
_logger.log(Level.FINE, "Connection Pool : " + poolName);
}
protected void initializePoolWaitQueue() throws PoolingException {
waitQueue = PoolWaitQueueFactory.createPoolWaitQueue(poolWaitQueueClass);
}
protected void initializePoolDataStructure() throws PoolingException {
ds = DataStructureFactory.getDataStructure(dataStructureType, dataStructureParameters,
maxPoolSize, this, resourceSelectionStrategyClass);
}
protected void initializeResourceSelectionStragegy() {
//do nothing
}
private void setPoolConfiguration() throws PoolingException {
ConnectorConnectionPool poolResource = getPoolConfigurationFromJndi();
idletime = Integer.parseInt(poolResource.getIdleTimeoutInSeconds()) * 1000;
maxPoolSize = Integer.parseInt(poolResource.getMaxPoolSize());
steadyPoolSize = Integer.parseInt(poolResource.getSteadyPoolSize());
if (maxPoolSize < steadyPoolSize) {
maxPoolSize = steadyPoolSize;
}
resizeQuantity = Integer.parseInt(poolResource.getPoolResizeQuantity());
maxWaitTime = Integer.parseInt(poolResource.getMaxWaitTimeInMillis());
//Make sure it's not negative.
if (maxWaitTime < 0) {
maxWaitTime = 0;
}
failAllConnections = poolResource.isFailAllConnections();
validation = poolResource.isIsConnectionValidationRequired();
validateAtmostEveryIdleSecs = poolResource.isValidateAtmostEveryIdleSecs();
dataStructureType = poolResource.getPoolDataStructureType();
dataStructureParameters = poolResource.getDataStructureParameters();
poolWaitQueueClass = poolResource.getPoolWaitQueue();
resourceSelectionStrategyClass = poolResource.getResourceSelectionStrategyClass();
resourceGatewayClass = poolResource.getResourceGatewayClass();
setAdvancedPoolConfiguration(poolResource);
}
protected ConnectorConnectionPool getPoolConfigurationFromJndi() throws PoolingException {
ConnectorConnectionPool poolResource;
try {
Context ic = ConnectorRuntime.getRuntime().getNamingManager().getInitialContext();
String jndiNameOfPool = ConnectorAdminServiceUtils.getReservePrefixedJNDINameForPool(name);
poolResource = (ConnectorConnectionPool) ic.lookup(jndiNameOfPool);
} catch (NamingException ex) {
throw new PoolingException(ex);
}
return poolResource;
}
// This method does not need to be synchronized since all caller methods are,
// but it does not hurt. Just to be safe.
protected synchronized void initPool(ResourceSpec resourceSpec,
ResourceAllocator allocator)
throws PoolingException {
if (poolInitialized) {
return;
}
this.resourceSpec = resourceSpec;
this.allocator = allocator;
createResources(this.allocator, steadyPoolSize - ds.getResourcesSize());
// if the idle time out is 0, then don't schedule the resizer task
if (idletime > 0) {
scheduleResizerTask();
}
poolInitialized = true;
}
/**
* Schedules the resizer timer task. If a task is currently scheduled,
* it would be canceled and a new one is scheduled.
*/
private void scheduleResizerTask() {
if (resizerTask != null) {
//cancel the current task
resizerTask.cancel();
resizerTask = null;
}
resizerTask = new Resizer(name, ds, this, this, preferValidateOverRecreate);
if (timer == null) {
timer = ConnectorRuntime.getRuntime().getTimer();
}
timer.scheduleAtFixedRate(resizerTask, idletime, idletime);
if (_logger.isLoggable(Level.FINEST)) {
_logger.finest("scheduled resizer task");
}
}
/**
* add a resource with status busy and not enlisted
*
* @param alloc ResourceAllocator
* @throws PoolingException when unable to add a resource
*/
public void addResource(ResourceAllocator alloc) throws PoolingException {
ds.addResource(alloc, 1);
if (_logger.isLoggable(Level.FINE)) {
_logger.log(Level.FINE, "Pool: resource added");
}
}
/**
* marks resource as free. This method should be used instead of directly calling
* resoureHandle.getResourceState().setBusy(false)
* OR
* getResourceState(resourceHandle).setBusy(false)
* as this method handles stopping of connection leak tracing
* If connection leak tracing is enabled, takes care of stopping
* connection leak tracing
*
* @param resourceHandle Resource
*/
protected void setResourceStateToFree(ResourceHandle resourceHandle) {
getResourceState(resourceHandle).setBusy(false);
leakDetector.stopConnectionLeakTracing(resourceHandle, this);
}
/**
* marks resource as busy. This method should be used instead of directly calling
* resoureHandle.getResourceState().setBusy(true)
* OR
* getResourceState(resourceHandle).setBusy(true)
* as this method handles starting of connection leak tracing
* If connection leak tracing is enabled, takes care of starting
* connection leak tracing
*
* @param resourceHandle Resource
*/
protected void setResourceStateToBusy(ResourceHandle resourceHandle) {
getResourceState(resourceHandle).setBusy(true);
leakDetector.startConnectionLeakTracing(resourceHandle, this);
}
/**
* returns resource from the pool.
*
* @return a free pooled resource object matching the ResourceSpec
* @throws PoolingException - if any error occurrs
* - or the pool has reached its max size and the
* max-connection-wait-time-in-millis has expired.
*/
public ResourceHandle getResource(ResourceSpec spec,
ResourceAllocator alloc,
Transaction tran) throws PoolingException {
//Note: this method should not be synchronized or the
// startTime would be incorrect for threads waiting to enter
/*
* Here are all the comments for the method put togethar for
* easy reference.
* 1.
// - Try to get a free resource. Note: internalGetResource()
// will create a new resource if none is free and the max has
// not been reached.
// - If can't get one, get on the wait queue.
// - Repeat this until maxWaitTime expires.
// - If maxWaitTime == 0, repeat indefinitely.
2.
//the doFailAllConnectionsProcessing method would already
//have been invoked by now.
//We simply go ahead and create a new resource here
//from the allocator that we have and adjust the resources
//list accordingly so as to not exceed the maxPoolSize ever
//(i.e if steadyPoolSize == maxPoolSize )
///Also since we are creating the resource out of the allocator
//that we came into this method with, we need not worry about
//matching
*/
ResourceHandle result = null;
long startTime = 0;
long elapsedWaitTime;
long remainingWaitTime = 0;
if (maxWaitTime > 0) {
startTime = System.currentTimeMillis();
}
while (true) {
if (gateway.allowed()) {
//See comment #1 above
try {
result = internalGetResource(spec, alloc, tran);
} finally {
gateway.acquiredResource();
}
}
if (result != null) {
// got one, return it
if (poolLifeCycleListener != null) {
poolLifeCycleListener.connectionAcquired();
elapsedWaitTime = System.currentTimeMillis() - startTime;
poolLifeCycleListener.connectionRequestServed(elapsedWaitTime);
}
//got one - seems we are not doing validation or matching
//return it
break;
} else {
// did not get a resource.
if (maxWaitTime > 0) {
elapsedWaitTime = System.currentTimeMillis() - startTime;
if (elapsedWaitTime < maxWaitTime) {
// time has not expired, determine remaining wait time.
remainingWaitTime = maxWaitTime - elapsedWaitTime;
} else {
// wait time has expired
if (poolLifeCycleListener != null) {
poolLifeCycleListener.connectionTimedOut();
}
String msg = localStrings.getStringWithDefault(
"poolmgr.no.available.resource",
"No available resource. Wait-time expired.");
throw new PoolingException(msg);
}
}
Object waitMonitor = waitQueue.addToQueue();
synchronized (waitMonitor) {
try {
logFine("Resource Pool: getting on wait queue");
waitMonitor.wait(remainingWaitTime);
} catch (InterruptedException ex) {
//Could be system shutdown.
break;
}
//try to remove in case that the monitor has timed
// out. We dont expect the queue to grow to great numbers
// so the overhead for removing inexistant objects is low.
if (_logger.isLoggable(Level.FINE)) {
_logger.log(Level.FINE, "removing wait monitor from queue: " + waitMonitor);
}
waitQueue.removeFromQueue(waitMonitor);
}
}
}
alloc.fillInResourceObjects(result);
return result;
}
/**
* Overridden in AssocWithThreadResourcePool to fetch the resource
* cached in the ThreadLocal
* In ConnectionPool this simply returns null.
*
* @param spec ResourceSpec
* @param alloc ResourceAllocator to create a resource
* @param tran Transaction
* @return ResourceHandle resource from ThreadLocal
*/
protected ResourceHandle prefetch(ResourceSpec spec,
ResourceAllocator alloc, Transaction tran) {
return null;
}
protected ResourceHandle internalGetResource(ResourceSpec spec,
ResourceAllocator alloc,
Transaction tran) throws PoolingException {
if (!poolInitialized) {
initPool(spec, alloc);
}
ResourceHandle result;
result = prefetch(spec, alloc, tran);
if (result != null) {
return result;
}
result = getResourceFromTransaction(tran, alloc, spec);
// We didnt get a connection that is already enlisted in the current transaction (if any).
if (result == null) {
result = getUnenlistedResource(spec, alloc, tran);
if (result != null) {
if (maxConnectionUsage_ > 0) {
result.incrementUsageCount();
}
if (poolLifeCycleListener != null) {
poolLifeCycleListener.connectionUsed();
}
}
}
return result;
}
/**
* Try to get a resource from current transaction if it is shareable
* @param tran Current Transaction
* @param alloc ResourceAllocator
* @param spec ResourceSpec
* @return result ResourceHandle
*/
private ResourceHandle getResourceFromTransaction(Transaction tran, ResourceAllocator alloc, ResourceSpec spec) {
ResourceHandle result = null;
try {
//comment-1: sharing is possible only if caller is marked
//shareable, so abort right here if that's not the case
if (tran != null && alloc.shareableWithinComponent()) {
//TODO V3 should be handled by PoolTxHelper
JavaEETransaction j2eetran = (JavaEETransaction) tran;
// case 1. look for free and enlisted in same tx
Set set = j2eetran.getResources(name);
if (set != null) {
Iterator iter = set.iterator();
while (iter.hasNext()) {
ResourceHandle h = (ResourceHandle) iter.next();
if (h.hasConnectionErrorOccurred()) {
iter.remove();
continue;
}
ResourceState state = h.getResourceState();
/*
* One can share a resource only for the following conditions:
* 1. The caller resource is shareable (look at the outermost
* if marked comment-1
* 2. The resource enlisted inside the transaction is shareable
* 3. We are dealing with XA resources OR
* We are deling with a non-XA resource that's not in use
* Note that sharing a non-xa resource that's in use involves
* associating physical connections.
* 4. The credentials of the resources match
*/
if (h.getResourceAllocator().shareableWithinComponent()) {
if (spec.isXA() || poolTxHelper.isNonXAResourceAndFree(j2eetran, h)) {
if (matchConnections) {
if (!alloc.matchConnection(h)) {
//TODO V3 : enable connectionNotMatched
/*if (poolLifeCycleListener != null) {
poolLifeCycleListener.connectionNotMatched();
}*/
continue;
}
if (h.hasConnectionErrorOccurred()) {
if (failAllConnections) {
//if failAllConnections has happened, we flushed the
//pool, so we don't have to do iter.remove else we
//will get a ConncurrentModificationException
result = null;
break;
}
iter.remove();
continue;
}
//TODO V3 : enabled matched counter here
/*if (poolLifeCycleListener != null) {
poolLifeCycleListener.connectionMatched();
}*/
}
if (state.isFree())
setResourceStateToBusy(h);
result = h;
break;
}
}
}
}
}
} catch (ClassCastException e) {
_logger.log(Level.FINE, "Pool: getResource : " +
"transaction is not J2EETransaction but a " + tran.getClass().getName(), e);
}
return result;
}
/**
* To provide an unenlisted, valid, matched resource from pool.
*
* @param spec ResourceSpec
* @param alloc ResourceAllocator
* @param tran Transaction
* @return ResourceHandle resource from pool
* @throws PoolingException Exception while getting resource from pool
*/
protected ResourceHandle getUnenlistedResource(ResourceSpec spec, ResourceAllocator alloc,
Transaction tran) throws PoolingException {
return getResourceFromPool(alloc, spec);
}
/**
* Check whether the connection is valid
*
* @param h Resource to be validated
* @param alloc Allocator to validate the resource
* @return boolean representing validation result
*/
private boolean isConnectionValid(ResourceHandle h, ResourceAllocator alloc) {
boolean connectionValid = true;
if (validation || validateAtmostEveryIdleSecs) {
long validationPeriod;
//validation period is idle timeout if validateAtmostEveryIdleSecs is set to true
//else it is validateAtmostPeriodInMilliSeconds_
if (validation)
validationPeriod = validateAtmostPeriodInMilliSeconds_;
else
validationPeriod = idletime;
boolean validationRequired = true;
long currentTime = h.getLastValidated();
if (validationPeriod > 0) {
currentTime = System.currentTimeMillis();
long timeSinceValidation = currentTime - h.getLastValidated();
if (timeSinceValidation < validationPeriod)
validationRequired = false;
}
if (validationRequired) {
if (!alloc.isConnectionValid(h)) {
connectionValid = false;
incrementNumConnFailedValidation();
} else {
h.setLastValidated(currentTime);
}
}
}
return connectionValid;
}
/**
* check whether the connection retrieved from the pool matches with the request.
*
* @param resource Resource to be matched
* @param alloc ResourceAllocator used to match the connection
* @return boolean representing the match status of the connection
*/
protected boolean matchConnection(ResourceHandle resource, ResourceAllocator alloc) {
boolean matched = true;
if (matchConnections) {
matched = alloc.matchConnection(resource);
//TODO V3 : enabled matched/unmatched
/*if (poolLifeCycleListener != null) {
if (matched) {
poolLifeCycleListener.connectionMatched();
} else {
poolLifeCycleListener.connectionNotMatched();
}
}*/
}
return matched;
}
/**
* return resource in free list. If none is found, try to scale up the pool/purge pool and
* return a new resource. returns null if the pool new resources cannot be created.
*
* @param alloc ResourceAllocator
* @return ResourceHandle resource from pool
* @throws PoolingException if unable to create a new resource
*/
protected ResourceHandle getResourceFromPool(ResourceAllocator alloc, ResourceSpec spec)
throws PoolingException {
// the order of serving a resource request
// 1. free and enlisted in the same transaction
// 2. free and unenlisted
// Do NOT give out a connection that is
// free and enlisted in a different transaction
ResourceHandle result = null;
ResourceHandle h;
ArrayList freeResources = new ArrayList();
try{
while ((h = ds.getResource()) != null) {
if (h.hasConnectionErrorOccurred()) {
ds.removeResource(h);
continue;
}
if (matchConnection(h, alloc)) {
boolean isValid = isConnectionValid(h, alloc);
if (h.hasConnectionErrorOccurred() || !isValid) {
if (failAllConnections) {
h = createSingleResourceAndAdjustPool(alloc, spec);
//no need to match since the resource is created with the allocator of caller.
break;
} else {
ds.removeResource(h);
//resource is invalid, continue iteration.
continue;
}
}
// got a matched, valid resource
result = h;
break;
} else {
freeResources.add(h);
}
}
}finally{
//return all unmatched, free resources
for (ResourceHandle freeResource : freeResources) {
ds.returnResource(freeResource);
}
freeResources.clear();
}
if (result != null) {
// set correct state
setResourceStateToBusy(result);
} else {
result = resizePoolAndGetNewResource(alloc);
}
return result;
}
/**
* Scale-up the pool to serve the new request.
* If pool is at max-pool-size and free resources are found, purge unmatched
* resources, create new connections and serve the request.
*
* @param alloc ResourceAllocator used to create new resources
* @return ResourceHandle newly created resource
* @throws PoolingException when not able to create resources
*/
private ResourceHandle resizePoolAndGetNewResource(ResourceAllocator alloc) throws PoolingException {
//Must be called from the thread holding the lock to this pool.
ResourceHandle result = null;
int numOfConnsToCreate = 0;
if (ds.getResourcesSize() < steadyPoolSize) {
// May be all invalid resources are destroyed as
// a result no free resource found and no. of resources is less than steady-pool-size
numOfConnsToCreate = steadyPoolSize - ds.getResourcesSize();
} else if (ds.getResourcesSize() + resizeQuantity <= maxPoolSize) {
//Create and add resources of quantity "resizeQuantity"
numOfConnsToCreate = resizeQuantity;
} else if (ds.getResourcesSize() < maxPoolSize) {
// This else if "test condition" is not needed. Just to be safe.
// still few more connections (less than "resizeQuantity" and to reach the count of maxPoolSize)
// can be added
numOfConnsToCreate = maxPoolSize - ds.getResourcesSize();
}
if (numOfConnsToCreate > 0) {
createResources(alloc, numOfConnsToCreate);
result = getMatchedResourceFromPool(alloc);
} else if (ds.getFreeListSize() > 0) {
//pool cannot create more connections as it is at max-pool-size.
//If there are free resources at max-pool-size, then none of the free resources
//has matched this allocator's request (credential). Hence purge free resources
//of size <=resizeQuantity
if (purgeResources(resizeQuantity) > 0) {
result = resizePoolAndGetNewResource(alloc);
}
}
return result;
}
//TODO V3 can't this be replaced by getResourceFromPool ?
private ResourceHandle getMatchedResourceFromPool(ResourceAllocator alloc) {
ResourceHandle handle;
ResourceHandle result = null;
ArrayList activeResources = new ArrayList();
try{
while ((handle = ds.getResource()) != null) {
if (matchConnection(handle, alloc)) {
result = handle;
setResourceStateToBusy(result);
break;
} else {
activeResources.add(handle);
}
}
}finally{
//return unmatched resources
for (ResourceHandle activeResource : activeResources) {
ds.returnResource(activeResource);
}
activeResources.clear();
}
return result;
}
/**
* Try to purge resources by size <= quantity
*
* @param quantity maximum no. of resources to remove.
* @return resourceCount No. of resources actually removed.
*/
private int purgeResources(int quantity) {
//Must be called from the thread holding the lock to this pool.
int totalResourcesRemoved = 0;
int freeResourcesCount = ds.getFreeListSize();
int resourcesCount = (freeResourcesCount >= quantity) ?
quantity : freeResourcesCount;
if (_logger.isLoggable(Level.FINE)) {
_logger.log(Level.FINE, "Purging resources of size : " + resourcesCount);
}
for (int i = resourcesCount - 1; i >= 0; i--) {
ResourceHandle resource = ds.getResource();
if (resource != null) {
ds.removeResource(resource);
totalResourcesRemoved += 1;
}
}
return totalResourcesRemoved;
}
/**
* This method will be called from the getUnenlistedResource method if
* we detect a failAllConnection flag.
* Here we simply create a new resource and replace a free resource in
* the pool by this resource and then give it out.
* This replacement is required since the steadypoolsize might equal
* maxpoolsize and in that case if we were not to remove a resource
* from the pool, our resource would be above maxPoolSize
*
* @param alloc ResourceAllocator to create resource
* @param spec ResourceSpec
* @return newly created resource
* @throws PoolingException when unable to create a resource
*/
protected ResourceHandle createSingleResourceAndAdjustPool(
ResourceAllocator alloc, ResourceSpec spec)
throws PoolingException {
ResourceHandle handle = ds.getResource();
if (handle != null) {
ds.removeResource(handle);
}
ResourceHandle result = getNewResource(alloc);
if (result != null) {
alloc.fillInResourceObjects(result);
result.getResourceState().setBusy(true);
}
return result;
}
/**
* Method to be used to create resource, instead of calling ResourceAllocator.createResource().
* This method handles the connection creation retrial in case of failure
*
* @param resourceAllocator ResourceAllocator
* @return ResourceHandle newly created resource
* @throws PoolingException when unable create a resource
*/
protected ResourceHandle createSingleResource(ResourceAllocator resourceAllocator) throws PoolingException {
ResourceHandle resourceHandle;
int count = 0;
while (true) {
try {
count++;
resourceHandle = resourceAllocator.createResource();
if (validation || validateAtmostEveryIdleSecs)
resourceHandle.setLastValidated(System.currentTimeMillis());
break;
} catch (Exception ex) {
_logger.log(Level.FINE, "Connection creation failed for " + count + " time. It will be retried, "
+ "if connection creation retrial is enabled.", ex);
if (!connectionCreationRetry_ || count >= connectionCreationRetryAttempts_)
throw new PoolingException(ex);
try {
Thread.sleep(conCreationRetryInterval_);
} catch (InterruptedException ie) {
//ignore this exception
}
}
}
return resourceHandle;
}
/**
* Create specified number of resources.
*
* @param alloc ResourceAllocator
* @param size number of resources to create.
* @throws PoolingException When unable to create a resource
*/
private void createResources(ResourceAllocator alloc, int size) throws PoolingException {
for (int i = 0; i < size; i++) {
createResourceAndAddToPool(alloc);
}
}
public void setPoolLifeCycleListener(PoolLifeCycleListener listener) {
this.poolLifeCycleListener = listener;
}
public void removePoolLifeCycleListener() {
poolLifeCycleListener = null;
}
public void deleteResource(ResourceHandle resourceHandle) {
try {
resourceHandle.getResourceAllocator().destroyResource(resourceHandle);
} catch (Exception ex) {
_logger.log(Level.WARNING, "poolmgr.destroy_resource_failed");
if (_logger.isLoggable(Level.FINE)) {
_logger.log(Level.FINE, "poolmgr.destroy_resource_failed", ex);
}
} finally {
//if connection leak tracing is running on connection being
//destroyed due to error, then stop it
if (resourceHandle.getResourceState().isBusy())
leakDetector.stopConnectionLeakTracing(resourceHandle, this);
if (poolLifeCycleListener != null) {
poolLifeCycleListener.connectionDestroyed();
if (resourceHandle.getResourceState().isBusy()) {
//Destroying a Connection due to error
poolLifeCycleListener.decrementConnectionUsed(true, steadyPoolSize);
} else {
//Destroying a free Connection
poolLifeCycleListener.decrementFreeConnectionsSize(steadyPoolSize);
}
}
}
}
/**
* this method is called to indicate that the resource is
* not used by a bean/application anymore
*/
public void resourceClosed(ResourceHandle h)
throws IllegalStateException {
if (_logger.isLoggable(Level.FINE)) {
_logger.log(Level.FINE, "Pool: resourceClosed: " + h);
}
ResourceState state = getResourceState(h);
if (state == null) {
throw new IllegalStateException("State is null");
}
if (!state.isBusy()) {
throw new IllegalStateException("state.isBusy() : false");
}
setResourceStateToFree(h); // mark as not busy
state.touchTimestamp();
if (state.isUnenlisted() || (poolTxHelper.isNonXAResource(h)
&& poolTxHelper.isLocalResourceEligibleForReuse(h))) {
freeUnenlistedResource(h);
}
if (poolLifeCycleListener != null) {
poolLifeCycleListener.connectionReleased();
}
if (_logger.isLoggable(Level.FINE)) {
_logger.log(Level.FINE, "Pool: resourceFreed: " + h);
}
}
/**
* If the resource is used for maxConnectionUsage times, destroy and create one
*
* @param handle Resource to be checked
*/
protected void performMaxConnectionUsageOperation(ResourceHandle handle) {
if (handle.getUsageCount() >= maxConnectionUsage_) {
ds.removeResource(handle);
_logger.log(Level.INFO, "resource_pool.remove_max_used_conn", handle.getUsageCount());
//compensate with a new resource only when the pool-size is less than steady-pool-size
if (ds.getResourcesSize() < steadyPoolSize) {
try {
createResourceAndAddToPool(handle.getResourceAllocator());
} catch (Exception e) {
_logger.log(Level.WARNING, "resource_pool.failed_creating_resource", e);
}
}
}
}
protected void freeUnenlistedResource(ResourceHandle h) {
freeResource(h);
}
protected void freeResource(ResourceHandle resourceHandle) {
// Put it back to the free collection.
ds.returnResource(resourceHandle);
//update the monitoring data
if (poolLifeCycleListener != null) {
poolLifeCycleListener.decrementConnectionUsed(false, steadyPoolSize);
}
if (maxConnectionUsage_ > 0) {
performMaxConnectionUsageOperation(resourceHandle);
}
//for both the cases of free.add and maxConUsageOperation, a free resource is added.
// Hence notify waiting threads
notifyWaitingThreads();
}
public void resourceErrorOccurred(ResourceHandle h)
throws IllegalStateException {
if (_logger.isLoggable(Level.FINE)) {
_logger.log(Level.FINE, "Pool: resourceErrorOccurred: " + h);
}
if (failAllConnections) {
doFailAllConnectionsProcessing();
return;
}
ResourceState state = getResourceState(h);
// The reason is that normally connection error is expected
// to occur only when the connection is in use by the application.
// When there is connection validation involved, the connection
// can be checked for validity "before" it is passed to the
// application i.e. when the resource is still free. Since,
// the connection error can occur when the resource
// is free, the following is being commented out.
/*if (state == null ||
state.isBusy() == false) {
throw new IllegalStateException();
} */
if (state == null) {
throw new IllegalStateException();
}
// changed order of commands
//Commenting resources.remove() out since we will call an iter.remove()
//in the getUnenlistedResource method in the if check after
//matchManagedConnections or in the internalGetResource method
//If we were to call remove directly here there is always the danger
//of a ConcurrentModificationExceptionbeing thrown when we return
//
//In case of this method being called asynchronously, since
//the resource has been marked as "errorOccured", it will get
//removed in the next iteration of getUnenlistedResource
//or internalGetResource
ds.removeResource(h);
}
private void doFailAllConnectionsProcessing() {
logFine("doFailAllConnectionsProcessing entered");
cancelResizerTask();
if (poolLifeCycleListener != null) {
poolLifeCycleListener.connectionValidationFailed(ds.getResourcesSize());
}
emptyPool();
try {
createResources(allocator, steadyPoolSize);
} catch (PoolingException pe) {
//Ignore and hope the resizer does its stuff
logFine("in doFailAllConnectionsProcessing couldn't create steady resources");
}
scheduleResizerTask();
logFine("doFailAllConnectionsProcessing done - created new resources");
}
/**
* this method is called when a resource is enlisted in
*
* @param tran Transaction
* @param resource ResourceHandle
*/
public void resourceEnlisted(Transaction tran, ResourceHandle resource)
throws IllegalStateException {
poolTxHelper.resourceEnlisted(tran, resource);
}
/**
* this method is called when transaction tran is completed
*
* @param tran Transaction
* @param status status of transaction
*/
public void transactionCompleted(Transaction tran, int status) throws IllegalStateException {
List delistedResources = poolTxHelper.transactionCompleted(tran, status, name);
for (ResourceHandle resource : delistedResources) {
// Application might not have closed the connection.
if (isResourceUnused(resource)) {
freeResource(resource);
}
}
}
protected boolean isResourceUnused(ResourceHandle h) {
return h.getResourceState().isFree();
}
public ResourceHandle createResource(ResourceAllocator alloc) throws PoolingException {
//NOTE : Pool should not call this method directly, it should be called only by pool-datastructure
ResourceHandle result = createSingleResource(alloc);
ResourceState state = new ResourceState();
state.setBusy(false);
state.setEnlisted(false);
result.setResourceState(state);
if (poolLifeCycleListener != null) {
poolLifeCycleListener.connectionCreated();
}
return result;
}
public void createResourceAndAddToPool() throws PoolingException {
createResourceAndAddToPool(allocator);
}
public Set getInvalidConnections(Set connections) throws ResourceException {
return allocator.getInvalidConnections(connections);
}
public void invalidConnectionDetected(ResourceHandle h) {
incrementNumConnFailedValidation();
}
public void resizePool(boolean forced) {
resizerTask.resizePool(forced);
}
protected void notifyWaitingThreads() {
// notify the first thread in the waitqueue
Object waitMonitor = null;
if (waitQueue.getQueueLength() > 0) {
waitMonitor = waitQueue.peek();
}
if (waitMonitor != null) {
synchronized (waitMonitor) {
if (_logger.isLoggable(Level.FINE)) {
_logger.log(Level.FINE, "Notifying wait monitor : " + waitMonitor.toString());
}
waitMonitor.notify();
}
} else {
logFine(" Wait monitor is null");
}
}
private void incrementNumConnFailedValidation() {
if (poolLifeCycleListener != null) {
poolLifeCycleListener.connectionValidationFailed(1);
}
}
private ResourceHandle getNewResource(ResourceAllocator alloc) throws PoolingException {
ds.addResource(alloc, 1);
return ds.getResource();
}
private ResourceState getResourceState(ResourceHandle h) {
return h.getResourceState();
}
public void emptyPool() {
if (_logger.isLoggable(Level.FINE)) {
_logger.log(Level.FINE, "EmptyPool: Name = " + name);
}
ds.removeAll();
}
public void emptyFreeConnectionsInPool() {
if (_logger.isLoggable(Level.FINE)) {
_logger.log(Level.FINE, "Emptying free connections in pool : " + name);
}
ResourceHandle h;
while ((h = ds.getResource()) != null) {
ds.removeResource(h);
}
}
public String toString() {
StringBuffer sb = new StringBuffer("Pool [");
sb.append(name);
sb.append("] PoolSize=");
sb.append(ds.getResourcesSize());
sb.append(" FreeResources=");
sb.append(ds.getFreeListSize());
sb.append(" QueueSize=");
sb.append(waitQueue.getQueueLength());
sb.append(" matching=");
sb.append((matchConnections ? "on" : "off"));
sb.append(" validation=");
sb.append((validation ? "on" : "off"));
return sb.toString();
}
/**
* Reconfigure the Pool's properties. The reconfigConnectorConnectionPool
* method in the ConnectorRuntime will use this method (through PoolManager)
* if it needs to just change pool properties and not recreate the pool
*
* @param poolResource - the ConnectorConnectionPool javabean that holds
* the new pool properties
* @throws PoolingException if the pool resizing fails
*/
public synchronized void reconfigPoolProperties(ConnectorConnectionPool poolResource)
throws PoolingException {
int _idleTime = Integer.parseInt(poolResource.getIdleTimeoutInSeconds())
* 1000;
if (poolInitialized) {
if (_idleTime != idletime && _idleTime != 0) {
scheduleResizerTask();
}
if (_idleTime == 0) {
//resizerTask.cancel();
cancelResizerTask();
}
}
idletime = _idleTime;
resizeQuantity = Integer.parseInt(poolResource.getPoolResizeQuantity());
maxWaitTime = Integer.parseInt(poolResource.getMaxWaitTimeInMillis());
//Make sure it's not negative.
if (maxWaitTime < 0) {
maxWaitTime = 0;
}
validation = poolResource.isIsConnectionValidationRequired();
failAllConnections = poolResource.isFailAllConnections();
setAdvancedPoolConfiguration(poolResource);
//Self managed quantities. These are ignored if self management
//is on
if (!isSelfManaged()) {
int _maxPoolSize = Integer.parseInt(poolResource.getMaxPoolSize());
if (_maxPoolSize < steadyPoolSize) {
//should not happen, admin must throw exception when this condition happens.
//as a precaution set max pool size to steady pool size
maxPoolSize = steadyPoolSize;
} else {
maxPoolSize = _maxPoolSize;
}
int _steadyPoolSize = Integer.parseInt(poolResource.getSteadyPoolSize());
int oldSteadyPoolSize = steadyPoolSize;
if (_steadyPoolSize > maxPoolSize) {
//should not happen, admin must throw exception when this condition happens.
//as a precaution set steady pool size to max pool size
steadyPoolSize = maxPoolSize;
} else {
steadyPoolSize = _steadyPoolSize;
}
if (poolInitialized) {
//In this case we need to kill extra connections in the pool
//For the case where the value is increased, we need not
//do anything
//num resources to kill is decided by the resources in the pool.
//if we have less than current maxPoolSize resources, we need to
//kill less.
int toKill = ds.getResourcesSize() - maxPoolSize;
if (toKill > 0)
killExtraResources(toKill);
}
if (oldSteadyPoolSize != steadyPoolSize) {
if (poolInitialized) {
if (oldSteadyPoolSize < steadyPoolSize)
increaseSteadyPoolSize(_steadyPoolSize);
} else if (poolLifeCycleListener != null) {
poolLifeCycleListener.connectionsFreed(steadyPoolSize);
}
}
}
}
/**
* sets advanced pool properties
* used during pool configuration (initialization) and re-configuration
*
* @param poolResource Connector Connection Pool
*/
private void setAdvancedPoolConfiguration(ConnectorConnectionPool poolResource) {
matchConnections = poolResource.matchConnections();
preferValidateOverRecreate = poolResource.isPreferValidateOverRecreate();
maxConnectionUsage_ = Integer.parseInt(poolResource.getMaxConnectionUsage());
connectionCreationRetryAttempts_ = Integer.parseInt
(poolResource.getConCreationRetryAttempts());
//Converting seconds to milliseconds as TimerTask will take input in milliseconds
conCreationRetryInterval_ =
Integer.parseInt(poolResource.getConCreationRetryInterval()) * 1000;
connectionCreationRetry_ = connectionCreationRetryAttempts_ > 0;
validateAtmostPeriodInMilliSeconds_ =
Integer.parseInt(poolResource.getValidateAtmostOncePeriod()) * 1000;
boolean connectionLeakReclaim_ = poolResource.isConnectionReclaim();
long connectionLeakTimeoutInMilliSeconds_ = Integer.parseInt(
poolResource.getConnectionLeakTracingTimeout()) * 1000;
boolean connectionLeakTracing_ = connectionLeakTimeoutInMilliSeconds_ > 0;
if (leakDetector == null) {
leakDetector = new ConnectionLeakDetector(name, connectionLeakTracing_,
connectionLeakTimeoutInMilliSeconds_, connectionLeakReclaim_);
} else {
leakDetector.reset(connectionLeakTracing_,
connectionLeakTimeoutInMilliSeconds_, connectionLeakReclaim_);
}
}
/*
* Kill the extra resources at the end of the Hashtable
* The maxPoolSize being reduced causes this method to
* be called
*/
private void killExtraResources(int numToKill) {
cancelResizerTask();
ResourceHandle h;
for (int i = 0; i < numToKill && ((h = ds.getResource()) != null); i++) {
ds.removeResource(h);
}
scheduleResizerTask();
}
/*
* Increase the number of steady resources in the pool
* if we detect that the steadyPoolSize has been increased
*/
private void increaseSteadyPoolSize(int newSteadyPoolSize)
throws PoolingException {
cancelResizerTask();
for (int i = ds.getResourcesSize(); i < newSteadyPoolSize; i++) {
createResourceAndAddToPool(allocator);
}
scheduleResizerTask();
}
/**
* @param alloc ResourceAllocator
* @throws PoolingException when unable to create a resource
*/
private void createResourceAndAddToPool(ResourceAllocator alloc) throws PoolingException {
addResource(alloc);
}
/**
* Switch on matching of connections in the pool.
*/
public void switchOnMatching() {
matchConnections = true;
}
/**
* query the name of this pool. Required by monitoring
*
* @return the name of this pool
*/
public String getPoolName() {
return name;
}
public synchronized void cancelResizerTask() {
logFine("Cancelling resizer");
if (resizerTask != null) {
resizerTask.cancel();
}
resizerTask = null;
if (timer != null) {
timer.purge();
}
}
/**
* This method can be used for debugging purposes
*/
public synchronized void dumpPoolStatus() {
_logger.log(Level.INFO, "Name of pool :" + name);
_logger.log(Level.INFO, "Free connections :" + ds.getFreeListSize());
_logger.log(Level.INFO, "Total connections :" + ds.getResourcesSize());
_logger.log(Level.INFO, "Pool's matching is :" + matchConnections);
}
private void logFine(String msg) {
if (_logger.isLoggable(Level.FINE)) {
_logger.fine(msg);
}
}
//Self management methods
public int getMaxPoolSize() {
return maxPoolSize;
}
public int getResizeQuantity() {
return resizeQuantity;
}
public long getIdleTimeout() {
return idletime;
}
public int getWaitQueueLength() {
return waitQueue.getQueueLength();
}
public int getSteadyPoolSize() {
return steadyPoolSize;
}
public void setMaxPoolSize(int size) {
if (size < ds.getResourcesSize()) {
synchronized (this) {
int toKill = ds.getResourcesSize() - size;
if (toKill > 0) {
try {
killExtraResources(toKill);
} catch (Exception re) {
//ignore for now
if (_logger.isLoggable(Level.FINE)) {
_logger.log(Level.FINE, "setMaxPoolSize:: killExtraResources " +
"throws exception: " + re.getMessage());
}
}
}
}
}
maxPoolSize = size;
}
public void setSteadyPoolSize(int size) {
steadyPoolSize = size;
}
public void setSelfManaged(boolean selfManaged) {
if (_logger.isLoggable(Level.FINE)) {
_logger.log(Level.FINE, "Setting selfManaged to : " + selfManaged + " in pool : " + name);
}
selfManaged_ = selfManaged;
}
protected boolean isSelfManaged() {
return selfManaged_;
}
public void potentialConnectionLeakFound() {
if (poolLifeCycleListener != null)
poolLifeCycleListener.foundPotentialConnectionLeak();
}
public void printConnectionLeakTrace(StringBuffer stackTrace) {
if (poolLifeCycleListener != null) {
String msg = localStrings.getStringWithDefault("monitoring.statistics", "Monitoring Statistics :");
stackTrace.append("\n");
stackTrace.append(msg);
stackTrace.append("\n");
//TODO V3 : change toString() to a more specific method name
poolLifeCycleListener.toString(stackTrace);
}
}
public void reclaimConnection(ResourceHandle handle) {
freeResource(handle);
}
}
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