IBM MQ classes for Java client connections

When IBM MQ classes for Java is used as a client, it is like the IBM MQ MQI client, but has a number of differences.

If we are programming for IBM MQ classes for Java for use as a client, be aware of the following differences:

• It supports only TCP/IP.
• It does not read any IBM MQ environment variables at startup.
• Information that would be stored in a channel definition and in environment variables can be stored in a class called Environment. Alternatively, this information can be passed as parameters when the connection is made.
• Error and exception conditions are written to a log specified in the MQException class. The default error destination is the Java console.
• Only the following attributes in an IBM MQ client configuration file are relevant to IBM MQ classes for Java. If you specify other attributes, they are ineffective.

  Stanza	Attribute
  ClientExitPath stanza of the client configuration file	ExitsDefaultPath
  ClientExitPath stanza of the client configuration file	ExitsDefaultPath64
  ClientExitPath stanza of the client configuration file	JavaExitsClasspath
  MessageBuffer stanza of the client configuration file	MaximumSize
  MessageBuffer stanza of the client configuration file	PurgeTime
  MessageBuffer stanza of the client configuration file	UpdatePercentage
  TCP stanza of the client configuration file	ClntRcvBuffSize
  TCP stanza of the client configuration file	ClntSndBuffSize
  TCP stanza of the client configuration file	Connect_Timeout
  TCP stanza of the client configuration file	KeepAlive

• If connecting to a queue manager that requires character data to be converted, then the V7 Java client is now capable of doing the conversion if queue manager is unable to do so. The client JVM must support the conversion between the CCSID of the client and that of the queue manager.
• Automatic client reconnect is not supported by IBM MQ classes for Java.

When used in client mode, IBM MQ classes for Java does not support the MQBEGIN call.

Parent topic: IBM MQ classes for Java connection modes