@Override
public void trigger(ChainReduceVertex vertex) throws IOException {
VertexMethod<String> m = methodFromConfig(vertex, findParentMethodKey, String.class);
String derivedParent = m.calculate(vertex);
Text msg = new Text("FIND_NEXT " + vertex.getId().toString());
vertex.sendMessage(new Text(derivedParent), msg);
}
@Override
public void handle(ChainReduceVertex vertex, String[] params) throws IOException {
final Text parentForwardLabel = textFromConfig(vertex, parentForwardLabelKey);
final Text parentReverseLabel = textFromConfig(vertex, parentReverseLabelKey);
final Text nextCandidateLabel = textFromConfig(vertex, nextCandidateLabelKey);
final Text prevCandidateLabel = textFromConfig(vertex, prevCandidateLabelKey);
final Text src = new Text(params[1]);
Text pTargetId = findEdgeByValue(vertex, parentForwardLabel);
if (pTargetId != null) {
Text candidate =
methodFromConfig(vertex, deriveEquivalentVertexKey, Text.class)
.calculate(vertex, src, pTargetId);
vertex.addEdgeRequest(src, new Edge<Text, Text>(candidate, nextCandidateLabel));
vertex.addEdgeRequest(candidate, new Edge<Text, Text>(src, prevCandidateLabel));
nudge(vertex, new Text(candidate));
} else {
vertex.addEdgeRequest(src, new Edge<Text, Text>(DUMMY_VERTEX, nextCandidateLabel));
}
Text rTargetId = findEdgeByValue(vertex, parentReverseLabel);
if (rTargetId != null) {
Text candidate =
methodFromConfig(vertex, deriveEquivalentVertexKey, Text.class)
.calculate(vertex, src, rTargetId);
vertex.addEdgeRequest(src, new Edge<Text, Text>(candidate, prevCandidateLabel));
vertex.addEdgeRequest(candidate, new Edge<Text, Text>(src, nextCandidateLabel));
nudge(vertex, new Text(candidate));
} else {
vertex.addEdgeRequest(src, new Edge<Text, Text>(DUMMY_VERTEX, prevCandidateLabel));
}
nudge(vertex, new Text(src));
}
void nudge(ChainReduceVertex vertex, Text target) {
if (target != null) {
vertex.sendMessage(target, new Text("_"));
}
}