Web Services Review Quiz

XML stands for Extensible Markup Language. It is a markup language that is used for encoding documents in a format that is both human-readable and machine-readable. XML is commonly used for representing web services components because it allows for the structured and organized representation of data. Unlike HTML, which is primarily used for displaying web pages, XML is designed to store and transport data. Therefore, XML is the correct answer for this question.

Web services are loosely coupled. Loosely coupled refers to a design principle where the components of a system are independent and can function separately from each other. In the case of web services, this means that the service provider and service consumer can evolve independently, without affecting each other. They can be developed and deployed using different technologies and platforms, as long as they adhere to a common set of standards and protocols for communication. This loose coupling allows for flexibility, scalability, and easier integration of different systems.

The Command Facade Pattern is the correct answer because it focuses on separating the business logic from the service implementation class. By using distinct business objects, the pattern allows for better management and evolution of the business logic over time. This pattern helps in simplifying the complexity of the service implementation class by providing a simplified interface to access the business logic.

XML digital signatures provide integrity by ensuring that the data within an XML document has not been tampered with or altered during transmission or storage. The digital signature uses cryptographic algorithms to create a unique hash value for the XML document, which is then encrypted using the sender's private key. This encrypted hash value is attached to the XML document, allowing the recipient to verify the integrity of the data by decrypting the hash value using the sender's public key and comparing it to a recalculated hash value of the received XML document. If the hash values match, it indicates that the XML document has not been modified and its integrity is preserved.

UDDI is a registry and a repository, but it does not store the actual content. Instead, it stores metadata and information about the content, such as functional specifications, implementation details, and business documents like schemas and WSDL. The actual content is stored elsewhere, and UDDI provides a way to locate and access that content. Therefore, the statement "False, because the actual content is never stored in UDDI" is the correct explanation.

A in WSDL refers to the operations that can be performed and the messages that are involved. It defines the set of operations that a web service can support and the types of messages that can be exchanged between the client and the server. The element provides a high-level view of the functionality provided by the web service. It specifies the input and output messages for each operation, as well as any faults that can occur.

The UDDI (Universal Description, Discovery, and Integration) specification defines various data types used in the UDDI registry. BusinessEntity, BusinessService, tModel, and BindingTemplate are all valid UDDI data types. However, BusinessTemplate is not a recognized UDDI data type.

A Direct Invocation Interface cannot be used as a Web Service Client because it does not have the necessary functionality to communicate with a web service. Direct invocation involves directly calling methods on an object, without any network communication. In contrast, a Web Service Client needs to be able to make remote procedure calls and interact with the web service over a network. Therefore, a Direct Invocation Interface is not suitable for this purpose.

The odd one out in this list is "Facade Service." The other options, such as Service Simulator, Configuration Driven Service, Data Logger, and Input/Output Validator, all seem to be related to the concept of service or functionality within a system. However, a Facade Service is a design pattern that provides a simplified interface to a larger body of code, acting as a "facade" or intermediary between the client and the underlying system. Therefore, it stands out as a different type of concept compared to the other options.

The element in WSDL defines the data types that are used by the web service. This includes the definition of complex types, simple types, and enumerations. The element, on the other hand, defines the message format and protocol details for each port. This includes specifying the encoding style, transport protocol, and other communication details. The element defines the data elements of an operation, including the input and output parameters.

SOAP (Simple Object Access Protocol) defines the overall structure of the XML message, including the conventions representing the remote procedure call in the XML message. It also provides a binding to HTTP, allowing the XML message to be transmitted over the internet. Additionally, SOAP specifies the conventions to wrap and send an error back to the sender, ensuring proper error handling in the communication process.

The WS-I (Web Services Interoperability) compliance defines a set of standards and guidelines for ensuring interoperability between web services. Both RPC/literal and Document/literal Wrapped styles are strictly WS-I compliant. The RPC/literal style represents method calls and responses using XML elements, while Document/literal Wrapped style uses XML elements to wrap the input and output parameters of a web service operation. These styles adhere to the WS-I standards and guidelines, ensuring compatibility and interoperability between different web services. The other styles mentioned, Document/encoded and RPC/encoded, are not strictly WS-I compliant.

UDDI (Universal Description, Discovery, and Integration) and WSIL (Web Services Inspection Language) both act as directories in Web Services. UDDI is a specification that provides a platform-independent registry for businesses to list and discover web services. It allows service providers to publish their services and service consumers to search and find the desired services. WSIL, on the other hand, is an XML-based format that provides a directory of available web services. It allows users to discover and browse through different web services available on a particular server. Therefore, both UDDI and WSIL can be considered as components of Web Services that act as directories.

The given correct answer states that "With ASP.NET you have to write your own WSDL and SOAP documents" is false. This means that in ASP.NET, you do not need to manually write WSDL and SOAP documents as they are automatically generated. Additionally, the answer states that "Document/literal Wrapped style of WSDL originates from JAX-RPC provided by SUN Microsystems" is false. This suggests that the Document/literal Wrapped style of WSDL does not originate from JAX-RPC but from another source.

JAXB 1.0 provided validation at unmarshal time, meaning that the validation of XML data against a schema occurred during the unmarshalling process. JAXB 2.0 expanded on this capability by allowing validation at both unmarshal and marshal time, meaning that the validation can also occur during the marshalling process. Additionally, JAXB 1.0 enabled on-demand validation on a JAXB content tree, allowing the validation to be triggered manually when needed.

The SOAPAction HTTP header is optional in SOAP 1.2. This means that it is not required to include this header in the SOAP message. SOAP 1.2 disallows partially transmitted and sparse arrays, which means that arrays must be transmitted in their entirety and cannot contain empty or missing elements. Additionally, SOAP 1.2 adds a new standard header for reporting additional information in "MustUnderstand" faults. This header provides a standardized way to communicate additional details about errors that occur when processing SOAP messages.

The statement "With JAX-WS, the developer generates/parses SOAP messages" is incorrect because with JAX-WS, the developer does not need to manually generate or parse SOAP messages. The JAX-WS runtime system takes care of converting the API calls and responses to and from SOAP messages.

The statement "A JAX-WS client cannot access a web service that is not running on the Java platform, and vice versa" is incorrect. A JAX-WS client can access web services running on platforms other than Java, and a Java web service can be accessed by clients running on different platforms.

The statement "For a JAX-WS Endpoint: The implementing class should not explicitly reference an SEI through the endpointInterface element of the @WebService annotation" is incorrect. In JAX-WS, the implementing class should explicitly reference a Service Endpoint Interface (SEI) through the endpointInterface element of the @WebService annotation.