public interface InvocationHandler
InvocationHandleris the interface implemented by the invocation handler of a proxy instance.
Each proxy instance has an associated invocation handler.
When a method is invoked on a proxy instance, the method
invocation is encoded and dispatched to the
method of its invocation handler.
proxy- the proxy instance that the method was invoked on
Methodinstance corresponding to the interface method invoked on the proxy instance. The declaring class of the
Methodobject will be the interface that the method was declared in, which may be a superinterface of the proxy interface that the proxy class inherits the method through.
args- an array of objects containing the values of the arguments passed in the method invocation on the proxy instance, or
nullif interface method takes no arguments. Arguments of primitive types are wrapped in instances of the appropriate primitive wrapper class, such as
nulland the interface method's return type is primitive, then a
NullPointerExceptionwill be thrown by the method invocation on the proxy instance. If the value returned by this method is otherwise not compatible with the interface method's declared return type as described above, a
ClassCastExceptionwill be thrown by the method invocation on the proxy instance.
Throwable- the exception to throw from the method invocation on the proxy instance. The exception's type must be assignable either to any of the exception types declared in the
throwsclause of the interface method or to the unchecked exception types
java.lang.Error. If a checked exception is thrown by this method that is not assignable to any of the exception types declared in the
throwsclause of the interface method, then an
UndeclaredThrowableExceptioncontaining the exception that was thrown by this method will be thrown by the method invocation on the proxy instance.
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