Package io.vertx.servicediscovery.types

Class AbstractServiceReference<T>

java.lang.Object

io.vertx.servicediscovery.types.AbstractServiceReference<T>

Type Parameters:

T - the type of service object

All Implemented Interfaces:

ServiceReference, AutoCloseable

public abstract class AbstractServiceReference<T>
extends Object
implements ServiceReference

A class to simplify the implementation of service reference. It stores the service object once retrieved. This class handles the synchronization, so callbacks are called with the monitor lock to avoid concurrent accesses.

Author:

Clement Escoffier

Field Summary

Fields

Modifier and Type	Field	Description
protected T	service
protected Vertx	vertx

Constructor Summary

Constructors

Constructor	Description
AbstractServiceReference(Vertx vertx, ServiceDiscovery discovery, Record record)	Creates a new instance of AbstractServiceReference.

Method Summary

Modifier and Type	Method	Description
<X> X	cached()	Returns the service object.
<X> X	cachedAs(Class<X> x)	GGets the service object if already retrieved.
void	close()	Same as release(), here to implement AutoCloseable.
<X> X	get()	Gets the service object.
<X> X	getAs(Class<X> x)	Gets the service object.
boolean	isHolding(Object object)	Checks whether or not the service reference has the given service object.
protected void	onClose()	Callback that let you cleanup the service object.
Record	record()
void	release()	If the service object has been retrieved, calls onClose() and release the reference.
protected abstract T	retrieve()	Method to implement to retrieve the service object.

Methods inherited from class java.lang.Object

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

Field Detail

service

protected T service

vertx

protected final Vertx vertx

Constructor Detail

AbstractServiceReference

public AbstractServiceReference(Vertx vertx,
                                ServiceDiscovery discovery,
                                Record record)

Creates a new instance of AbstractServiceReference.

Parameters:

vertx - the vert.x instance

record - the service record

Method Detail

cached

public <X> X cached()

Returns the service object. If not retrieved or released, it returns null.

Specified by:

cached in interface ServiceReference

Returns:

the cached service object, null if none

get

public <X> X get()

Gets the service object. If not retrieved, call retrieve(), otherwise returned the cached value.

Specified by:

get in interface ServiceReference

Returns:

the service object

getAs

public <X> X getAs(Class<X> x)

Gets the service object. It can be a proxy, a client or whatever object depending on the service type. Unlike get() this method let you configure the type of object you want to retrieve. This parameter must match the expected service type, and must pass the "polyglot" version of the class.

Specified by:

getAs in interface ServiceReference

Type Parameters:

X - the type of object

Parameters:

x - the

Returns:

the object to access the service

cachedAs

public <X> X cachedAs(Class<X> x)

GGets the service object if already retrieved. It won't try to acquire the service object if not retrieved yet. Unlike cached() this method let you configure the type of object you want to retrieve. This parameter must match the expected service type, and must pass the "polyglot" version of the class.

Specified by:

cachedAs in interface ServiceReference

Type Parameters:

X - the type of object

Parameters:

x - the

Returns:

the object to access the service

retrieve

protected abstract T retrieve()

Method to implement to retrieve the service object. It can be a proxy creation, or a new client. This method is called once, then the return is cached.

Returns:

the service object

onClose

protected void onClose()

Callback that let you cleanup the service object. This callback is only called if the service objects has been retrieved.

record

public Record record()

Specified by:

record in interface ServiceReference

Returns:

the service record.

release

public void release()

If the service object has been retrieved, calls onClose() and release the reference. Otherwise, does nothing.

Specified by:

release in interface ServiceReference

close

public void close()

Same as release(), here to implement AutoCloseable.

Specified by:

close in interface AutoCloseable

isHolding

public boolean isHolding(Object object)

Description copied from interface: ServiceReference

Checks whether or not the service reference has the given service object.

Specified by:

isHolding in interface ServiceReference

Parameters:

object - the service object, must not be null

Returns:

true if the service reference service object is equal to the given object, false otherwise.