Interface ConnectorRequestInterceptor

All Known Implementing Classes:
DebugRequestInterceptor

public interface ConnectorRequestInterceptor

A request interceptor. An interceptor allows intercepting the request created by a connector. See handleInvocation(ConnectorInvocation) for more details and usage patters.

The interceptor is invoked for every request created by a connector. As such, an interceptor implementation must be thread-safe.

Author:
Daniel Meyer
  • Method Details

    • handleInvocation

      Object handleInvocation(ConnectorInvocation invocation) throws Exception

      Intercept and handle the actual invocation. An implementation of this method *must* call invocation.proceed(); and return the result:

        public Object handleInvocation(ConnectorInvocation invocation) throws Exception {
          // do something before the request
          try {
            Object result = invocation.proceed();
            // do something after a successful request
            return result;
          } catch(Exception e) {
            // do something after a failed request
            throw e;
          }
        }
       

      This may be useful for "management" use cases such as logging, failure tracking etc... and modifying the Thread context of the request thread (Security Context, Transactions, ...).

      It is also possible for an implementation to access and modify the low level "raw" request object before it is executed by the connector:

        public Object handleInvocation(ConnectorInvocation invocation) throws Exception {
          Object rawRequest = invocation.getTarget();
          // cast rawRequest to the low-level connector implementation object and work with it.
      
          // finally
          return invocation.proceed();
        }
       
      Parameters:
      invocation - the invocation
      Returns:
      the result of the invocation
      Throws:
      Exception