spring - Only one thread is utilized in the ThreadPoolTaskExecutor and JMS -

I have a JMS message listener that is configured by Spring. However ThreadPoolTaskExecutor is configured for the original pool size 15, I think it is only the fulfillment of a thread requests, and the others are waiting for me to be a finite line, but I do not think that spring I Why does this allow it?

Here is the configuration:

  & lt; Bean id = "connectionFactory" class = "org.springframework.jndi.jndiObjectFactoryBean" & gt; & Lt; Property Name = "jndiName" value = "java: / ConnectionFactory" /> & Lt; Property Name = "jndiTemplate" ref = "jndiTemplate" /> & Lt; / Bean & gt; & Lt; Bean id = "destination" category = "org.springframework.jndi.JndiObjectFactoryBean" & gt; & Lt; Property name = "jndiName" value = "qi / some questions" /> & Lt; Property Name = "jndiTemplate" ref = "jndiTemplate" /> & Lt; / Bean & gt; & Lt; Bean id = "Jms Receive Destination Resolver" class = "org.springframework.jms.support.destination.JndiDestinationResolver" & gt; & Lt; Property Name = "jndiTemplate" ref = "jndiTemplate" /> & Lt; / Bean & gt; & Lt; Bean id = "some listener" category = "com.company.SomeListener" & gt; & Lt; Property Name = "..." ref = "..." /> & Lt; / Bean & gt; & Lt; jms: listener-container connections-factory = "connectionFactory" destination-type = "line" destination-resolver = "jmsReceiveDestinationResolver" performer = "jmsTaskExecutor" & gt; & Lt; JMS: listeners destination = "queue / some questions" riff = "message listener" /> & Lt; / Jms: listener-container & gt; & Lt; Bean name = "jmtask excl." Class = "org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor" & gt; & Lt; Property name = "core polish size" value = "15" /> & Lt; Property Name = "maxPoolSize" value = "50" /> & Lt; Property Name = "ThreadNamePrint" value = "Some-Queue-Thread" /> & Lt; / Bean & gt;   
 The 14 thread stack trace of waiting:  
  "something Pankti- thread7" prio = 10 TID = 0x000000004dcfc800 nid = on 0x1d90 Waiting condition [0x00000000435f7000] java.lang.Thread.State: waiting for sun.misc.Unsafe.park (parking) - parking & lt wait; 0x000000070f5abad8 & gt; java.util.concurrent.locks.LockSupport.park (LockSupport.java:158) on java.util.concurrent.locks.AbstractQueuedSynchronizer $ ConditionObject.await (a java.util.concurrent.locks.AbstractQueuedSynchronizer $ ConditionObject) (AbstractQueuedSynchronizer. Java: 1987) on java.util.concurrent.LinkedBlockingQueue.take (LinkedBlockingQueue.java:399) java.util.concurrent.ThreadPoolExecutor.getTask (ThreadPoolExecutor.java:947) java.util.concurrent.ThreadPoolExecutor at $ Worker.run at java.lang.Thread.run (ThreadPoolExecutor.java:907) (Thread.java:662)   
 Notice that it may be similar, but the core of my case pool plus sizes 1   
 
 
 says that you  & lt; Maximum identical users with jms need to specify: Listener-Container Synagimation = "15" ... & gt; , otherwise it would be 1.