Dynamic Method Invocation (DMI) is a feature of Struts2 framework that lets the "!" (bang) character invoke a method other than `execute`.
Dynamic Method Invocation (DMI) is a feature of Struts2 framework that lets the "!" (bang) character invoke a method other than execute. The "!" character added to the URL after the action name and followed by a method name to execute. The difference with the mapping actions in this way as the opposite where the action is mapped directly to the method in the action configuration the any other method could be executed regardless of the method configured or the method execute which is used by default.
This feature is configurable by the property or constant struts.enable.DynamicMethodInvocation which can take values true or false. By default this feature is enabled.
Since Struts 2.3, an option was added to restrict the methods that DMI can invoke. You can use the attribute strict-method-invocation="true" of the package tag. In this case Struts will reject any method that is not defined in the method attribute or allowed-methods of the action tag.
Documentation: http://struts.apache.org/docs/action-configuration.html#ActionConfiguration-DynamicMethodInvocation
