Handler (Java EE 5 SDK)

javax.xml.rpc.handler Interface Handler

所有已知实现子孙类:

GenericHandler

public interface Handler

The javax.xml.rpc.handler.Handler interface is required to be implemented by a SOAP message handler. The handleRequest, handleResponse and handleFault methods for a SOAP message handler get access to the SOAPMessage from the SOAPMessageContext. The implementation of these methods can modify the SOAPMessage including the headers and body elements.

版本:

1.0

作者:

Rahul Sharma

handleRequest

boolean handleRequest(MessageContext context)

The handleRequest method processes the request message.

参数:

context - MessageContext parameter provides access to the request message.

返回:

boolean Indicates the processing mode

• Return true to indicate continued processing of the request handler chain. The HandlerChain takes the responsibility of invoking the next entity. The next entity may be the next handler in the HandlerChain or if this handler is the last handler in the chain, the next entity is the service endpoint object.
• Return false to indicate blocking of the request handler chain. In this case, further processing of the request handler chain is blocked and the target service endpoint is not dispatched. The JAX-RPC runtime system takes the responsibility of invoking the response handler chain next with the SOAPMessageContext. The Handler implementation class has the the responsibility of setting the appropriate response SOAP message in either handleRequest and/or handleResponse method. In the default processing model, the response handler chain starts processing from the same Handler instance (that returned false) and goes backward in the execution sequence.

抛出异常:

JAXRPCException - This exception indicates handler specific runtime error. If JAXRPCException is thrown by a handleRequest method, the HandlerChain terminates the further processing of this handler chain. On the server side, the HandlerChain generates a SOAP fault that indicates that the message could not be processed for reasons not directly attributable to the contents of the message itself but rather to a runtime error during the processing of the message. On the client side, the exception is propagated to the client code

SOAPFaultException - This indicates a SOAP fault. The Handler implementation class has the the responsibility of setting the SOAP fault in the SOAP message in either handleRequest and/or handleFault method. If SOAPFaultException is thrown by a server-side request handler's handleRequest method, the HandlerChain terminates the further processing of the request handlers in this handler chain and invokes the handleFault method on the HandlerChain with the SOAP message context. Next, the HandlerChain invokes the handleFault method on handlers registered in the handler chain, beginning with the Handler instance that threw the exception and going backward in execution. The client-side request handler's handleRequest method should not throw the SOAPFaultException.

handleResponse

boolean handleResponse(MessageContext context)

The handleResponse method processes the response SOAP message.

参数:

context - MessageContext parameter provides access to the response SOAP message

返回:

boolean Indicates the processing mode

• Return true to indicate continued processing ofthe response handler chain. The HandlerChain invokes the handleResponse method on the next Handler in the handler chain.
• Return false to indicate blocking of the response handler chain. In this case, no other response handlers in the handler chain are invoked.

抛出异常:

JAXRPCException - Indicates handler specific runtime error. If JAXRPCException is thrown by a handleResponse method, the HandlerChain terminates the further processing of this handler chain. On the server side, the HandlerChain generates a SOAP fault that indicates that the message could not be processed for reasons not directly attributable to the contents of the message itself but rather to a runtime error during the processing of the message. On the client side, the runtime exception is propagated to the client code.

handleFault

boolean handleFault(MessageContext context)

The handleFault method processes the SOAP faults based on the SOAP message processing model.

参数:

context - MessageContext parameter provides access to the SOAP message

返回:

boolean Indicates the processing mode

• Return true to indicate continued processing of SOAP Fault. The HandlerChain invokes the handleFault method on the next Handler in the handler chain.
• Return false to indicate end of the SOAP fault processing. In this case, no other handlers in the handler chain are invoked.

抛出异常:

JAXRPCException - Indicates handler specific runtime error. If JAXRPCException is thrown by a handleFault method, the HandlerChain terminates the further processing of this handler chain. On the server side, the HandlerChain generates a SOAP fault that indicates that the message could not be processed for reasons not directly attributable to the contents of the message itself but rather to a runtime error during the processing of the message. On the client side, the JAXRPCException is propagated to the client code.

init

void init(HandlerInfo config)

The init method enables the Handler instance to initialize itself. The init method passes the handler configuration as a HandlerInfo instance. The HandlerInfo is used to configure the Handler (for example: setup access to an external resource or service) during the initialization.

In the init method, the Handler class may get access to any resources (for example; access to a logging service or database) and maintain these as part of its instance variables. Note that these instance variables must not have any state specific to the SOAP message processing performed in the various handle method.

参数:

HandlerInfo - Configuration for the initialization of this handler

抛出异常:

JAXRPCException - If initialization of the handler fails

destroy

void destroy()

The destroy method indicates the end of lifecycle for a Handler instance. The Handler implementation class should release its resources and perform cleanup in the implementation of the destroy method.

抛出异常:

JAXRPCException - If any error during destroy

getHeaders

QName[] getHeaders()

Gets the header blocks that can be processed by this Handler instance.

返回:

Array of QNames of header blocks processed by this handler instance. QName is the qualified name of the outermost element of the Header block.

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