NullPointerException

[jayzch]

Caused by: java.lang.NullPointerException: null at
org.springframework.amqp.rabbit.connection.SimpleConnection.createChannel(SimpleConnection.java:59) at org.springframework.amqp.rabbit.connection.CachingConnectionFactory$ChannelCachingConnectionProxy.createBareChannel(CachingConnectionFactory.java:1156) at org.springframework.amqp.rabbit.connection.CachingConnectionFactory$ChannelCachingConnectionProxy.access$200(CachingConnectionFactory.java:1144) at org.springframework.amqp.rabbit.connection.CachingConnectionFactory.doCreateBareChannel(CachingConnectionFactory.java:585) at org.springframework.amqp.rabbit.connection.CachingConnectionFactory.createBareChannel(CachingConnectionFactory.java:568) at org.springframework.amqp.rabbit.connection.CachingConnectionFactory.getCachedChannelProxy(CachingConnectionFactory.java:538) at org.springframework.amqp.rabbit.connection.CachingConnectionFactory.getChannel(CachingConnectionFactory.java:520) at org.springframework.amqp.rabbit.connection.CachingConnectionFactory.access$1500(CachingConnectionFactory.java:94) at org.springframework.amqp.rabbit.connection.CachingConnectionFactory$ChannelCachingConnectionProxy.createChannel(CachingConnectionFactory.java:1161) at org.springframework.amqp.rabbit.connection.ConnectionFactoryUtils$1.createChannel(ConnectionFactoryUtils.java:112) at org.springframework.amqp.rabbit.connection.ConnectionFactoryUtils.doGetTransactionalResourceHolder(ConnectionFactoryUtils.java:173) at org.springframework.amqp.rabbit.connection.ConnectionFactoryUtils.getTransactionalResourceHolder(ConnectionFactoryUtils.java:92) at org.springframework.amqp.rabbit.core.RabbitTemplate.doExecute(RabbitTemplate.java:1802) at org.springframework.amqp.rabbit.core.RabbitTemplate.execute(RabbitTemplate.java:1784) at org.springframework.amqp.rabbit.core.RabbitTemplate.send(RabbitTemplate.java:864) at org.springframework.amqp.rabbit.core.RabbitTemplate.convertAndSend(RabbitTemplate.java:927) at org.springframework.amqp.rabbit.core.RabbitTemplate.convertAndSend(RabbitTemplate.java:910) at

[garyrussell]

That implies the underlying rabbit connection returned no channel, which should not be possible.

Please show your configuration. the code that exhibits this behavior, together with version information for all libraries.

[jayzch]

    <spring-amqp.version>2.0.2.RELEASE</spring-amqp.version>

I changed different rabbit mq server .
At First , a number of servers conneted to the same RabbitMQ Server.
The problem occur when I connect to this RabbitMQ Server where maxChannel = 10

The problem disappeared when I connect to this RabbitMQ Server where maxChannel = 0

And then I solved the problem by setting maxChannel to 0.

But I think the framework should not threw NullPointerException.

[artembilan]

Not clear, what you show to us, @jayzch .
That's why Gary asked about some code to reproduce.

Indeed, Framework should not throw NPE, but you see your comment is not readable and we can't understand that stack trace properly. If you could format it the standard console output way, that would be helpful. Anyway +1 for some code to reproduce. Otherwise neither we can help you, nor you for us to fix the problem if it is there.

Thank you for understanding.

[jayzch]

This problem occurs when the number of RabbitMQ Server channels exceeds the limit maxChannel

[artembilan]

OK! Let it be. But how to reproduce, please?
Why also don't edit the mentioned stack trace to help us to read it clearly?

[garyrussell]

It's a bit odd that the client returns null in this case rather than throwing an exception.

I think the assertion should be made regardless of whether a transaction is being used.

[garyrussell]

It is odd, indeed, but clear in the javadocs...

/**
 * Create a new channel, using an internally allocated channel number.
 * If <a href="http://www.rabbitmq.com/api-guide.html#recovery">automatic connection recovery</a>
 * is enabled, the channel returned by this method will be {@link Recoverable}.
 *
 * @return a new channel descriptor, or null if none is available
 * @throws IOException if an I/O problem is encountered
 */
Channel createChannel() throws IOException;