WaveCrest Web Legacy Services

One of the challenges for legacy developers is the integration of their legacy software routines with new applications and/or web services. The WaveCrest Web Legacy Services software is designed to let the legacy developer expose legacy routines and business logic to other applications. This promotes the reuse of proven legacy code and saves time and money by eliminating the need to rewrite complex business logic in another web service compatible language.

The Web Legacy Services product allows the legacy programmer to provide legacy routines to networked or web clients using a language neutral interface. These legacy routines (or services) can be accessed using standard SOAP calls from any application.

The WLS software provides a C API to interact with your legacy application. This API provides a set of functions that can be called to process service requests. If your legacy language can access C functions then the C API provides an easy to use solution.

Many legacy languages can not access C functions. We provide several other options for communicating between your legacy application and the WLS server. The WLS server can also communicate to your application via sockets, stdin/stdout, or files.

A WLS service is implemented through one or more interface routines written in the legacy language. These routines act as a link between the legacy programs and the WLS Server, passing variable information, opening files, and performing whatever is needed to invoke the legacy program logic.

The WLS software provides support for basic variable types such as integer, double, string, etc. In addition to this you can pass Vector’s and Objects even though the legacy language may not support it. A set of calls are provided to create these data types within the WLS server from the legacy variable values. Each service can receive multiple parameters of any type and return an Object. The return value can be any of the supported variable types. Due to the Vector and Object support, large amounts of data such as string arrays or text files can be returned from the legacy services. This is useful when requesting information to be displayed by the calling application. The WLS software also provides a service to let the legacy application throw a SOAP fault to the client application. This fault includes a string message set by the legacy application that can be used by the calling application to determine the cause of the error.

The WLS software let’s you configure how your legacy programs are invoked. You can define whether a single instance of the legacy application handles one or multiple calls and when to launch new instances of the application in response to service requests. In addition to this, session support is provided so that the legacy application can preserve its process state between service calls.

© 2002 WaveCrest Software, Inc