TransactionFilter (Top level OA4MP 5.6 API)

```
public interface TransactionFilter
```
A Filter pattern for working with servlets. Every servlet that can/does work with transactions will invoke these methods as needed. Do recall that the servlet will still have all the machinery from its AbstractEnvironment available.
Created by Jeff Gaynor
on 4/23/12 at 4:39 PM

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`postprocess(TransactionState transactionState)`	Invoked after the response has been written to the `HttpServletResponse` stream.
`void`	`preprocess(TransactionState transactionState)`	Invoked after the transaction state has been determined, but before writing any response

- Method Detail
  - preprocess
```
void preprocess(TransactionState transactionState)
         throws Throwable
```
    Invoked after the transaction state has been determined, but before writing any response
    
    Parameters:
    
    transactionState -
    
    Throws:
    
    Throwable
  - postprocess
```
void postprocess(TransactionState transactionState)
          throws Throwable
```
    Invoked after the response has been written to the HttpServletResponse stream. This is the very last call made by the servlet before returning.
    
    Parameters:
    
    transactionState -
    
    Throws:
    
    Throwable