Package org.jgroups.blocks

Class RpcDispatcher

java.lang.Object

org.jgroups.blocks.MessageDispatcher

org.jgroups.blocks.RpcDispatcher

All Implemented Interfaces:

Closeable, AutoCloseable, RequestHandler, ChannelListener

public class RpcDispatcher
extends MessageDispatcher

This class allows a programmer to invoke remote methods in all (or single) group members and optionally wait for the return value(s).

An application will typically create a channel and layer the RpcDispatcher building block on top of it, which allows it to dispatch remote methods (client role) and at the same time be called by other members (server role).

This class is derived from MessageDispatcher.

Nested Class Summary

Nested classes/interfaces inherited from class org.jgroups.blocks.MessageDispatcher

MessageDispatcher.ProtocolAdapter

Field Summary

Fields

Modifier and Type	Field	Description
protected MethodInvoker	method_invoker
protected MethodLookup	method_lookup
protected Object	server_obj

Fields inherited from class org.jgroups.blocks.MessageDispatcher

async_dispatching, async_rsp_handling, channel, corr, empty_group_request, empty_rsplist, local_addr, log, members, prot_adapter, receiver, req_handler, wrap_exceptions

Constructor Summary

Constructors

Constructor	Description
RpcDispatcher()
RpcDispatcher(JChannel channel, Object server_obj)

Method Summary

Modifier and Type	Method	Description
<T> T	callRemoteMethod(Address dest, String meth, Object[] args, Class<?>[] types, RequestOptions opts)	Invokes a method in a cluster member and - if blocking - returns the result
<T> T	callRemoteMethod(Address dest, MethodCall call, RequestOptions options)	Invokes a method in a cluster member and - if blocking - returns the result
<T> RspList<T>	callRemoteMethods(Collection<Address> dests, String method_name, Object[] args, Class<?>[] types, RequestOptions options)	Invokes a method in all members and expects responses from members contained in dests (or all members if dests is null).
<T> RspList<T>	callRemoteMethods(Collection<Address> dests, MethodCall method_call, RequestOptions opts)	Invokes a method in all members and expects responses from members contained in dests (or all members if dests is null).
<T> CompletableFuture<RspList<T>>	callRemoteMethodsWithFuture(Collection<Address> dests, MethodCall call, RequestOptions options)	Invokes a method in all members and expects responses from members contained in dests (or all members if dests is null).
<T> CompletableFuture<T>	callRemoteMethodWithFuture(Address dest, MethodCall call, RequestOptions opts)	Invokes a method in a cluster member and - if blocking - returns the result
MethodInvoker	getMethodInvoker()
MethodLookup	getMethodLookup()
Object	getServerObject()
Object	handle(Message req)	Message contains MethodCall.
RpcDispatcher	setMethodInvoker(MethodInvoker mi)
RpcDispatcher	setMethodLookup(MethodLookup ml)
RpcDispatcher	setReceiver(Receiver r)
RpcDispatcher	setServerObject(Object obj)

Methods inherited from class org.jgroups.blocks.MessageDispatcher

_sendMessage, asyncDispatching, asyncDispatching, asyncRspHandling, asyncRspHandling, cast, castMessage, castMessageWithFuture, channelClosed, channelDisconnected, close, correlator, correlator, createRequestCorrelator, getAsyncDispatching, getChannel, getCorrelator, getProtocolAdapter, getState, getWrapExceptions, handle, handleUpEvent, installUpHandler, protocolAdapter, rpcStats, sendMessage, sendMessageWithFuture, setAsynDispatching, setChannel, setCorrelator, setMembers, setRequestHandler, setState, setWrapExceptions, start, stop, wrapExceptions, wrapExceptions

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.jgroups.ChannelListener

channelConnected

Field Details

server_obj

protected Object server_obj

method_lookup

protected MethodLookup method_lookup

method_invoker

protected MethodInvoker method_invoker

Constructor Details

RpcDispatcher

public RpcDispatcher()

RpcDispatcher

public RpcDispatcher(JChannel channel,
 Object server_obj)

Method Details

getServerObject

public Object getServerObject()

setServerObject

public RpcDispatcher setServerObject(Object obj)

setReceiver

public RpcDispatcher setReceiver(Receiver r)

Overrides:

setReceiver in class MessageDispatcher

getMethodLookup

public MethodLookup getMethodLookup()

setMethodLookup

public RpcDispatcher setMethodLookup(MethodLookup ml)

getMethodInvoker

public MethodInvoker getMethodInvoker()

setMethodInvoker

public RpcDispatcher setMethodInvoker(MethodInvoker mi)

callRemoteMethods

public <T> RspList<T> callRemoteMethods(Collection<Address> dests,
 String method_name,
 Object[] args,
 Class<?>[] types,
 RequestOptions options)
                                 throws Exception

Invokes a method in all members and expects responses from members contained in dests (or all members if dests is null).

Parameters:

dests - A list of addresses. If null, we'll wait for responses from all cluster members

method_name - The name of the target method

args - The arguments to be passed

types - The types of the arguments

options - A collection of call options, e.g. sync versus async, timeout etc

Returns:

RspList A response list with results, one for each member in dests, or null if the RPC is asynchronous

Throws:

Exception - If the sending of the message threw an exception. Note that no exception will be thrown if any of the target members threw an exception, but this exception will be in the Rsp object for the particular member in the RspList

callRemoteMethods

public <T> RspList<T> callRemoteMethods(Collection<Address> dests,
 MethodCall method_call,
 RequestOptions opts)
                                 throws Exception

Invokes a method in all members and expects responses from members contained in dests (or all members if dests is null).

Parameters:

dests - A list of addresses. If null, we'll wait for responses from all cluster members

method_call - The method (plus args) to be invoked

opts - A collection of call options, e.g. sync versus async, timeout etc

Returns:

RspList A list of return values and flags (suspected, not received) per member, or null if the RPC is asynchronous

Throws:

Exception - If the sending of the message threw an exception. Note that no exception will be thrown if any of the target members threw an exception, but this exception will be in the Rsp object for the particular member in the RspList

Since:

2.9

callRemoteMethodsWithFuture

public <T> CompletableFuture<RspList<T>> callRemoteMethodsWithFuture(Collection<Address> dests,
 MethodCall call,
 RequestOptions options)
                                                              throws Exception

Invokes a method in all members and expects responses from members contained in dests (or all members if dests is null).

Parameters:

dests - A list of addresses. If null, we'll wait for responses from all cluster members

call - The method (plus args) to be invoked

options - A collection of call options, e.g. sync versus async, timeout etc

Returns:

CompletableFuture A future from which the results can be fetched, or null if the RPC is asynchronous

Throws:

Exception - If the sending of the message threw an exception. Note that no exception will be thrown if any of the target members threw an exception; such an exception will be in the Rsp element for the particular member in the RspList

callRemoteMethod

public <T> T callRemoteMethod(Address dest,
 String meth,
 Object[] args,
 Class<?>[] types,
 RequestOptions opts)
                       throws Exception

Invokes a method in a cluster member and - if blocking - returns the result

Parameters:

dest - The target member on which to invoke the method

meth - The name of the method

args - The arguments

types - The types of the arguments

opts - The options (e.g. blocking, timeout etc)

Returns:

The result. Null if the call is asynchronous (non-blocking) or if the method returns void

Throws:

Exception - Thrown if the method invocation threw an exception, either at the caller or the callee

callRemoteMethod

public <T> T callRemoteMethod(Address dest,
 MethodCall call,
 RequestOptions options)
                       throws Exception

Invokes a method in a cluster member and - if blocking - returns the result

Parameters:

dest - The target member on which to invoke the method

call - The call to be invoked, including method are arguments

options - The options (e.g. blocking, timeout etc)

Returns:

The result. Null if the call is asynchronous (non-blocking) or if the method returns void

Throws:

Exception - Thrown if the method invocation threw an exception, either at the caller or the callee

callRemoteMethodWithFuture

public <T> CompletableFuture<T> callRemoteMethodWithFuture(Address dest,
 MethodCall call,
 RequestOptions opts)
                                                    throws Exception

Invokes a method in a cluster member and - if blocking - returns the result

Parameters:

dest - The target member on which to invoke the method

call - The call to be invoked, including method are arguments

opts - The options (e.g. blocking, timeout etc)

Returns:

A future from which the result can be fetched. If the callee threw an invocation, an ExecutionException will be thrown on calling Future.get(). If the invocation was asynchronous, null will be returned.

Throws:

Exception - Thrown if the method invocation threw an exception

handle

public Object handle(Message req)
              throws Exception

Message contains MethodCall. Execute it against *this* object and return result. Use MethodCall.invoke() to do this. Return result.

Specified by:

handle in interface RequestHandler

Overrides:

handle in class MessageDispatcher

Parameters:

req - the message containing the request

Returns:

the object, rceeived as result, or null (void method)

Throws:

Exception