Configuring Wire Formats

Using ActiveMQ Classic > Configuring Transports > ActiveMQ Classic Connection URIs > Configuring Wire Format

The OpenWire Wire Format

OpenWire is the default wire format used by ActiveMQ Classic. It provides a highly efficient binary format for high speed messaging. OpenWire options can be configured on a JMS client’s connection URI or on a broker’s transport bind URI.

Option	Default	Description
`cacheEnabled`	`true`	Should commonly repeated values be cached so that less marshaling occurs?
`cacheSize`	`1024`	When `cacheEnabled=true` then this parameter is used to specify the number of values to be cached.
`maxInactivityDuration`	`30000`	The maximum inactivity duration (before which the socket is considered dead) in milliseconds. On some platforms it can take a long time for a socket to die. Therefore allow the broker to kill connections when they have been inactive for the configured period of time. Used by some transports to enable a keep alive heart beat feature. Inactivity monitoring is disabled when set to a value `<= 0`.
`maxInactivityDurationInitalDelay`	`10000`	The initial delay before starting inactivity checks. Yes, the word `'Inital'` is supposed to be misspelled like that.
`maxFrameSize`	`MAX_LONG`	Maximum allowed frame size. Can help help prevent OOM DOS attacks.
`maxFrameSizeEnabled`	`true`	Should the maxFrameSize check be verified? (since: v5.16.4)
`sizePrefixDisabled`	`false`	Should the size of the packet be prefixed before each packet is marshaled?
`stackTraceEnabled`	`true`	Should the stack trace of exception that occur on the broker be sent to the client?
`tcpNoDelayEnabled`	`true`	Does not affect the wire format, but provides a hint to the peer that `TCP_NODELAY` should be enabled on the communications Socket.
`tightEncodingEnabled`	`true`	Should wire size be optimized over CPU usage?

Use the Correct Prefix!

Wire format options must have the prefix wireFormat. to take effect, e.g., wireFormat.maxInactivityDuration=10000. Options missing this prefix will be ignored.

Example Configurations

Java:

ActiveMQConnectionFactory cf = new ActiveMQConnectionFactory("tcp://localhost:61616?wireFormat.cacheEnabled=false&wireFormat.tightEncodingEnabled=false");

Spring:

<bean class="org.apache.activemq.ActiveMQConnectionFactory">
  <property name="brokerURL" value="failover:(tcp://localhost:61616?jms.optimizeAcknowledge=false&wireFormat.maxInactivityDuration=30000)"/>
  <!-- other options... -->
</bean>

Max Frame Size:

The maxFrameSizeEnabled check applies to both the client and server-side. The setting is not transferred from the server to the client during wireformat negotiation. This allows clients and servers to configure independently (generally only for testing).