InterceptorChain (synapse-core 0.24.1 API)

java.lang.Object
- de.otto.synapse.endpoint.InterceptorChain

All Implemented Interfaces:

MessageInterceptor
```
@ThreadSafe
public final class InterceptorChain
extends java.lang.Object
implements MessageInterceptor
```
Implementation of the Composite pattern for message interceptors that can be used to build chains of interceptors.
Just like any other MessageInterceptor, the InterceptorChain is used to process a message before it is consumed by message consumers on the receiver-side, or before it is sent by a message sender to the channel infrastructure.

The interceptors of the InterceptorChain will be called in order. The result of the first interceptor is propagated to the next interceptor, and so on.

If an interceptor returns null, the chain will return null without further processing of the message.

See Also:

Composite Pattern

Constructor Summary

Constructors
Constructor	Description
`InterceptorChain()`	Creates an empty InterceptorChain.
`InterceptorChain(com.google.common.collect.ImmutableList<MessageInterceptor> messageInterceptors)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`com.google.common.collect.ImmutableList<MessageInterceptor>`	`getInterceptors()`	Returns the immutable list of registered `message interceptors`.
`TextMessage`	`intercept(TextMessage message)`	Intercepts a message using all registered interceptors and returns the resulting message.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - InterceptorChain
```
public InterceptorChain()
```
    Creates an empty InterceptorChain.
  - InterceptorChain
```
public InterceptorChain(com.google.common.collect.ImmutableList<MessageInterceptor> messageInterceptors)
```
- Method Detail
  - getInterceptors
```
public com.google.common.collect.ImmutableList<MessageInterceptor> getInterceptors()
```
    Returns the immutable list of registered message interceptors.
    
    Returns:
    
    registered message interceptors
  - intercept
```
@Nullable
public TextMessage intercept(@Nonnull
                             TextMessage message)
```
    Intercepts a message using all registered interceptors and returns the resulting message.
    The interceptors are called in order. The result of one interceptor is propagated to the next interceptor in the chain, until the end of the chain is reached, or one interceptor has returned null.
    
    If null is returned, the message must be dropped by the AbstractMessageEndpoint.
    
    Every interceptor may transform the message, or may take additional actions like, for example, logging, monitoring or other things.
    
    Specified by:
    
    intercept in interface MessageInterceptor
    
    Parameters:
    
    message - the message to intercept
    
    Returns:
    
    the (possibly modified) message, or null if the message should be dropped.