The InvocationContext object provides information that enables interceptor methods to control the behavior of the invocation chain.
public interface InvocationContext {
public Object getTarget();
public Object getTimer();
public Method getMethod();
public Constructor<?> getConstructor();
public Object[] getParameters();
public void setParameters(Object[] params);
public java.util.Map<String, Object> getContextData();
public Object proceed() throws Exception;
}The same InvocationContext instance is passed to each interceptor method for a given target class method or lifecycle event interception.
The InvocationContext instance allows an interceptor method to save information in the Map obtained via the getContextData method. This information can subsequently be retrieved and/or updated by other interceptor methods in the invocation chain, and thus serves as a means to pass contextual data between interceptors. The contextual data is not sharable across separate target class method or or lifecycle callback event invocations. The lifecycle of the InvocationContext instance is otherwise unspecified.
If interceptor methods are invoked as a result of the invocation on a web service endpoint, the map returned by getContextData will be the JAX-WS MessageContext [bib4].
The getTarget method returns the associated target instance. For around-construct lifecycle callback interceptor methods, getTarget returns null if called before the proceed method returns.
The getTimer method returns the timer object associated with a timeout method invocation. The getTimer method returns null for interceptor method types other than around-timeout interceptor methods.
The getMethod method returns the method of the target class for which the current interceptor method was invoked. The getMethod returns null in a lifecycle callback interceptor method for which there is no corresponding lifecycle callback method declared in the target class (or inherited from a superclass) or in an around-construct lifecycle callback interceptor method.
The getConstructor method returns the constructor of the target class for which the current around-construct interceptor method was invoked. The getConstructor method returns null for interceptor method types other than around-construct interceptor methods.
The getParameters method returns the parameters of the method or constructor invocation. If the setParameters method has been called, getParameters returns the values to which the parameters have been set.
The setParameters method modifies the parameters used for the invocation of the target class method or constructor. Modifying the parameter values does not affect the determination of the method or the constructor that is invoked on the target class. The parameter types must match the types for the target class method or constructor, and the number of parameters supplied must equal the number of parameters on the target class method or {fn-3}, or the IllegalArgumentException is thrown to the setParameters call.
The proceed method causes the invocation of the next interceptor method in the chain or, when called from the last around-invoke or around-timeout interceptor method, the target class method. For around-construct lifecycle callback interceptor methods, the invocation of the proceed method in the last interceptor method in the chain causes the target instance to be created. Interceptor methods must always call the InvocationContext.proceed method or no subsequent interceptor methods, target class method, or lifecycle callback methods will be invoked, or—in the case of around-construct interceptor methods—the target instance will not be created. The proceed method returns the result of the next method invoked. If a method is of type void , the invocation of the proceed method returns null . For around-construct lifecycle callback interceptor methods, the invocation of proceed in the last interceptor method in the chain causes the target instance to be created. For all other lifecycle callback interceptor methods, if there is no lifecycle callback interceptor method defined on the target class, the invocation of proceed in the last interceptor method in the chain is a no-{fn-4}, and null is returned.