io.reactivex.netty.contexts

Class ContextsContainerImpl

java.lang.Object

io.reactivex.netty.contexts.ContextsContainerImpl

All Implemented Interfaces:

ContextsContainer

public class ContextsContainerImpl
extends java.lang.Object
implements ContextsContainer

An implementation of ContextsContainer

Thread safety

Since the contexts can be concurrently modified/added this class needs to be thread safe.
However, generally the concurrency will be low as typically a requests is not concurrently processed by multiple threads. This is the reason, this implementation chooses to do brute-force thread-safety by making all public methods synchronized.
This context must not be used across requests.

Constructor Summary

Constructors

Constructor and Description
ContextsContainerImpl(ContextKeySupplier keySupplier)

Method Summary

Modifier and Type	Method and Description
void	addContext(java.lang.String contextName, java.lang.String context) Adds a custom String context to this request scope.
<T> void	addContext(java.lang.String contextName, T context, ContextSerializer<T> serializer) Adds a custom context (arbitrary object) to this container.
void	consumeBidirectionalContextsFromResponse(ContextKeySupplier contextKeySupplier) Reads the bi-directional contexts from the HTTP response and updates this ContextsContainer with those contexts.
<T> T	getContext(java.lang.String contextName) Retrieves the value of the context added previously in this request scope via ContextsContainer.addContext(String, String) or ContextsContainer.addContext(String, Object, ContextSerializer) The context could have been set in a different service and transferred here on the wire.
<T> T	getContext(java.lang.String contextName, ContextSerializer<T> serializer) Retrieves the value of the context added previously in this request scope via ContextsContainer.addContext(String, String) or ContextsContainer.addContext(String, Object, ContextSerializer) The context could have been set in a different service and transferred here on the wire.
java.util.Map<java.lang.String,java.lang.String>	getModifiedBidirectionalContexts() Map of bi-directional context names and values (serialized form) that were modified within the current application.
java.util.Map<java.lang.String,java.lang.String>	getSerializedContexts() Map of context names and values (serialized form) associated with this request.
boolean	removeContext(java.lang.String contextName) Removes a context with name contextName added previously in this request scope via ContextsContainer.addContext(String, String) or ContextsContainer.addContext(String, Object, ContextSerializer) The context could have been set in a different service and transferred here on the wire.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ContextsContainerImpl

public ContextsContainerImpl(ContextKeySupplier keySupplier)

Method Detail

addContext

public <T> void addContext(java.lang.String contextName,
                           T context,
                           ContextSerializer<T> serializer)

Description copied from interface: ContextsContainer

Adds a custom context (arbitrary object) to this container.

This context will be passed for all outbound service calls made by RxClient.
Serialization/de-serialization mechanism for this context will be delegated to serializer. Serialization will be done when an outbound service call is made, to send this context on the wire.

De-serialization will be done in the outbound service for the above call, if and only if, a client invokes ContextsContainer.getContext(String) for the same context name. This method overwrites any existing value with the passed context name.

Context updates:

If the context is mutable, then every mutation should add the context back here otherwise, the mutation will be lost when the context gets passed to a remote application.

Bi-directional contexts:

The following scenario counts as an update to a bi-directional context:

• The added context is bi-directional.
• There already is a value associated with this context name.
• The associated value is of the same class as the new value.
• The associated value is not equal to the new value as indicated by Object.equals(Object)

In case this is actually an update, any subsequent calls to ContextsContainer.getModifiedBidirectionalContexts() will also include this context.

Specified by:

addContext in interface ContextsContainer

Type Parameters:

T - Type of the context.

Parameters:

contextName - Name of the context.

context - Context instance.

serializer - Serializer for the context.

addContext

public void addContext(java.lang.String contextName,
                       java.lang.String context)

Description copied from interface: ContextsContainer

Adds a custom String context to this request scope.
This has exactly the same effect as calling ContextsContainer.addContext(String, Object, ContextSerializer) with the serializer as StringSerializer

Specified by:

addContext in interface ContextsContainer

Parameters:

contextName - Name of the context.

context - Context instance.

removeContext

public boolean removeContext(java.lang.String contextName)

Description copied from interface: ContextsContainer

Removes a context with name contextName added previously in this request scope via ContextsContainer.addContext(String, String) or ContextsContainer.addContext(String, Object, ContextSerializer)

The context could have been set in a different service and transferred here on the wire.

Specified by:

removeContext in interface ContextsContainer

Parameters:

contextName - Name of the context to remove.

Returns:

true if the context existed and was removed. false if the context did not exist.

getContext

public <T> T getContext(java.lang.String contextName)
                 throws ContextSerializationException

Description copied from interface: ContextsContainer

Retrieves the value of the context added previously in this request scope via ContextsContainer.addContext(String, String) or ContextsContainer.addContext(String, Object, ContextSerializer)

The context could have been set in a different service and transferred here on the wire. In such a case, the serializer passed during addition of the context will be used for de-serialization.

All values of the context after de-serialization are cached, unless overwritten by a corresponding ContextsContainer.addContext(String, Object, ContextSerializer). Also, the serializer instance will be cached once created.

Specified by:

getContext in interface ContextsContainer

Parameters:

contextName - Name of the context.

Throws:

ContextSerializationException

getContext

public <T> T getContext(java.lang.String contextName,
                        ContextSerializer<T> serializer)
                 throws ContextSerializationException

Description copied from interface: ContextsContainer

Retrieves the value of the context added previously in this request scope via ContextsContainer.addContext(String, String) or ContextsContainer.addContext(String, Object, ContextSerializer)

The context could have been set in a different service and transferred here on the wire. In such a case, the serializer passed will be used for de-serialization and the serializer passed during context addition will be ignored.

Word of caution: If the value is cached as a result of a prior invocation of this method or ContextsContainer.getContext(String), the passed serializer will not be used.

This method should only be used if your serializer is stateful or requires custom initializations. Otherwise, the serializer associated with this context must be used i.e. by calling ContextsContainer.getContext(String)

All values of the context after de-serialization are cached, unless overwritten by a corresponding ContextsContainer.addContext(String, Object, ContextSerializer). Also, the serializer instance will be cached once created.

Specified by:

getContext in interface ContextsContainer

Parameters:

contextName - Name of the context.

serializer - The serializer instance to use if the context is required to be de-serialized.

Throws:

ContextSerializationException

getSerializedContexts

public java.util.Map<java.lang.String,java.lang.String> getSerializedContexts()
                                                                       throws ContextSerializationException

Description copied from interface: ContextsContainer

Map of context names and values (serialized form) associated with this request.

Specified by:

getSerializedContexts in interface ContextsContainer

Returns:

Immutable map of name and value of the contexts. Empty map if none present.

Throws:

ContextSerializationException - If the serialization fails.

getModifiedBidirectionalContexts

public java.util.Map<java.lang.String,java.lang.String> getModifiedBidirectionalContexts()
                                                                                  throws ContextSerializationException

Description copied from interface: ContextsContainer

Map of bi-directional context names and values (serialized form) that were modified within the current application. See BiDirectional for details.

Specified by:

getModifiedBidirectionalContexts in interface ContextsContainer

Returns:

Immutable map of name and value of the contexts. Empty map if none present.

Throws:

ContextSerializationException - If the serialization fails.

consumeBidirectionalContextsFromResponse

public void consumeBidirectionalContextsFromResponse(ContextKeySupplier contextKeySupplier)
                                              throws ContextSerializationException

Description copied from interface: ContextsContainer

Reads the bi-directional contexts from the HTTP response and updates this ContextsContainer with those contexts.

Specified by:

consumeBidirectionalContextsFromResponse in interface ContextsContainer

Parameters:

contextKeySupplier - The ContextKeySupplier for the response.

Throws:

ContextSerializationException - If the de-serialization of the bidrectional context fails.