Introduction
This chapter is about making Spring interact with another piece of software over a network. Different protocols can be used for this, but each one of them uses a client/server architecture. Spring can be the client or server.
Java RMI and HTTP Invoker are remote method invocation technologies; a Java client executes a method located on a Java server just as with a normal method. The request contains the method's arguments and the response contains the method's return value.
Hessian, REST, and SOAP are web services; the request is an HTTP request to a web server, which sends back an HTTP response. Web services are platform agnostic; for example, the client could be a Spring application (Java) and the server could be a PHP application.
REST is currently the most popular option; it's simple, flexible, and cross-platform.
As a rule of thumb, use:
- HTTP Invoker to interact with another Spring application
- Java RMI to interact with another Java application not using Spring...
