org.apache.hadoop.hive.ql.lib.NodeProcessor Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
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package org.apache.hadoop.hive.ql.lib;
import java.util.Stack;
import org.apache.hadoop.hive.ql.parse.SemanticException;
/**
* Base class for processing operators which is no-op. The specific processors
* can register their own context with the dispatcher.
*/
public interface NodeProcessor {
/**
* Generic process for all ops that don't have specific implementations.
*
* @param nd
* operator to process
* @param procCtx
* operator processor context
* @param nodeOutputs
* A variable argument list of outputs from other nodes in the walk
* @return Object to be returned by the process call
* @throws SemanticException
*/
Object process(Node nd, Stack stack, NodeProcessorCtx procCtx,
Object... nodeOutputs) throws SemanticException;
}