Class Channel<Data extends Channel.Config>

java.lang.Object

org.apidesign.jvm.channel.Channel<Data>

Type Parameters:

Data - internal data of the channel

All Implemented Interfaces:

AutoCloseable

public final class Channel<Data extends Channel.Config>
extends Object
implements AutoCloseable

Channel connects two JVM instances. A "channel" creates two (almost) identical instances of the Channel on both sides of the "channel" - e.g. in each of the JVMs. The instances are initialized with the same Channel.Config, so they both understand the same messages when communicating with each other.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Channel.Config	Set of methods necessary for construction of a Channel.

Method Summary

Modifier and Type	Method	Description
void	close()
static <D extends Channel.Config> Channel<D>	create(JVM jvm, Class<? extends D> configClass)	Factory method to initialize the Channel in the SubstrateVM.
final <C, R extends C> R	execute(Class<C> resultType, Function<? super Channel<Data>, R> msg)	Executes a message in the other JVM.
final Data	getConfig()	Getter for data associated with the channel.
boolean	isDualJvmMode()	Check for "real dual JVM mode".
final boolean	isMaster()	Master channel check.
String	toString()

Methods inherited from class Object

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

Method Details

create

public static <D extends Channel.Config> Channel<D> create(JVM jvm,
 Class<? extends D> configClass)

Factory method to initialize the Channel in the SubstrateVM.

Type Parameters:

D - type of internal data as well as provider of the pool

Parameters:

jvm - instance of HotSpot JVM to connect to (can be null to create a mock channel inside of a single JVM)

configClass - the class which has public default constructor and can supply an instance of persistance pool to use for communication

Returns:

channel for sending messages to the HotSpot JVM

getConfig

public final Data getConfig()

Getter for data associated with the channel. Each instance of Channel on both sides of the "channel" gets different instance of Data. The data may be used in the functions that implement the logic in execute(Class, Function) message processing.

Returns:

data associated with this channel

See Also:

• execute(Class, Function)

isMaster

public final boolean isMaster()

Master channel check. One instance of the Channel on the initializing side is marked as master. The other one is slave.

Returns:

is master

isDualJvmMode

public boolean isDualJvmMode()

Check for "real dual JVM mode". There is a way to create a channel in a "mock mode" via create(org.apidesign.ni.jvm.channel.JVM, java.lang.Class) - such emulation is running both sides of the channel in the same JVM. One can detect such a situation by checking result of this method.

Returns:

true when two different JVMs are on each side of the channel. false otherwise, for example in the "mock mode".

execute

public final <C, R extends C> R execute(Class<C> resultType,
 Function<? super Channel<Data>, R> msg)

Executes a message in the other JVM. The message is any subclass of Function ready to be serialized/deserialized via channel's Channel.Config. The result (which is of type R) also has to be registered for serialization/deserialization.

Type Parameters:

C - the actual type of the Channel.Config subclass

R - the type of result we expect the message to return

Parameters:

resultType - class with the type of R to use for deserialization

msg - the message that gets serialized, transferred into the other JVM, deserialized on the other side and evaluated there

Returns:

the value gets computed via Function.apply(T) of msg in the other JVM and then it gets serialized and transferred back to us. Deserialized and the value is then returned from this method

close

public void close()
           throws Exception

Specified by:

close in interface AutoCloseable

Throws:

Exception

toString

public String toString()

Overrides:

toString in class Object