import org.apache.tinkerpop.gremlin.process.computer.MessageCombiner; //导入依赖的package包/类
public synchronized void addMessage(M message, MessageScope scope, Map<MessageScope,Integer> scopeMap,
                                    MessageCombiner<M> combiner) {
    assert message!=null && scope!=null && combiner!=null;
    Preconditions.checkArgument(scopeMap.containsKey(scope),"Provided scope was not declared in the VertexProgram: %s",scope);
    assert scopeMap.containsKey(scope);
    initializeCurrentMessages(scopeMap);
    if (scopeMap.size()==1) {
        if (currentMessages==null) currentMessages = message;
        else currentMessages = combiner.combine(message,(M)currentMessages);
    } else {
        int pos = scopeMap.get(scope);
        Object[] msgs =  (Object[])currentMessages;
        if (msgs[pos]==null) msgs[pos]=message;
        else msgs[pos] = combiner.combine(message,(M)msgs[pos]);
    }
}
 

import org.apache.tinkerpop.gremlin.process.computer.MessageCombiner; //导入依赖的package包/类
private void mergeViewIncomingPayload(final ViewIncomingPayload<M> viewIncomingPayload, final MessageCombiner<M> messageCombiner) {
    if (this.view == null)
        this.view = viewIncomingPayload.view;
    else
        this.view.addAll(viewIncomingPayload.getView());

    for (final M message : viewIncomingPayload.getIncomingMessages()) {
        this.mergeMessage(message, messageCombiner);
    }
}
 

import org.apache.tinkerpop.gremlin.process.computer.MessageCombiner; //导入依赖的package包/类
public void mergePayload(final Payload payload, final MessageCombiner<M> messageCombiner) {
    if (null == payload)
        return;
    if (payload instanceof ViewPayload)
        this.view = ((ViewPayload) payload).getView();
    else if (payload instanceof MessagePayload)
        this.mergeMessage(((MessagePayload<M>) payload).getMessage(), messageCombiner);
    else if (payload instanceof ViewIncomingPayload)
        this.mergeViewIncomingPayload((ViewIncomingPayload<M>) payload, messageCombiner);
    else
        throw new IllegalArgumentException("The provided payload is an unsupported merge payload: " + payload);
}
 

import org.apache.tinkerpop.gremlin.process.computer.MessageCombiner; //导入依赖的package包/类
public TinkerMessenger(final Vertex vertex, final TinkerMessageBoard<M> messageBoard, final Optional<MessageCombiner<M>> combiner) {
    this.vertex = vertex;
    this.messageBoard = messageBoard;
    this.combiner = combiner.isPresent() ? combiner.get() : null;
}
 

import org.apache.tinkerpop.gremlin.process.computer.MessageCombiner; //导入依赖的package包/类
@Override
public Optional<MessageCombiner<Double>> getMessageCombiner() {
    return (Optional) PageRankMessageCombiner.instance();
}
 

import org.apache.tinkerpop.gremlin.process.computer.MessageCombiner; //导入依赖的package包/类
@Override
public Optional<MessageCombiner<TraverserSet<Object>>> getMessageCombiner() {
    return (Optional) TraversalVertexProgramMessageCombiner.instance();
}
 

import org.apache.tinkerpop.gremlin.process.computer.MessageCombiner; //导入依赖的package包/类
@Override
public void setConf(final ImmutableClassesGiraphConfiguration configuration) {
    this.configuration = configuration;
    final Configuration apacheConfiguration = ConfUtil.makeApacheConfiguration(configuration);
    this.messageCombiner = (MessageCombiner) VertexProgram.createVertexProgram(HadoopGraph.open(apacheConfiguration), apacheConfiguration).getMessageCombiner().get();
}
 

import org.apache.tinkerpop.gremlin.process.computer.MessageCombiner; //导入依赖的package包/类
public ViewIncomingPayload(final MessageCombiner<M> messageCombiner) {
    this.incomingMessages = null == messageCombiner ? new ArrayList<>() : new ArrayList<>(1);
}
 

import org.apache.tinkerpop.gremlin.process.computer.MessageCombiner; //导入依赖的package包/类
private void mergeMessage(final M message, final MessageCombiner<M> messageCombiner) {
    if (this.incomingMessages.isEmpty() || null == messageCombiner)
        this.incomingMessages.add(message);
    else
        this.incomingMessages.set(0, messageCombiner.combine(this.incomingMessages.get(0), message));
}
 

import org.apache.tinkerpop.gremlin.process.computer.MessageCombiner; //导入依赖的package包/类
@Override
public Optional<MessageCombiner<Long>> getMessageCombiner() {
    return (Optional) ShortestDistanceMessageCombiner.instance();
}
 

import org.apache.tinkerpop.gremlin.process.computer.MessageCombiner; //导入依赖的package包/类
public static<M> MessageCombiner<M> getMessageCombiner(VertexProgram<M> program) {
    return program.getMessageCombiner().orElse(DEFAULT_COMBINER);
}
 

import org.apache.tinkerpop.gremlin.process.computer.MessageCombiner; //导入依赖的package包/类
public DuctileMessenger(Vertex vertex, DuctileMessageBoard<M> messageBoard, Optional<MessageCombiner<M>> combiner) {
this.vertex = vertex;
this.messageBoard = messageBoard;
this.combiner = combiner.isPresent() ? combiner.get() : null;
   }