/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.solr.client.solrj.io.eval;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import java.util.UUID;
import org.apache.solr.client.solrj.io.stream.StreamContext;
import org.apache.solr.client.solrj.io.stream.expr.Explanation;
import org.apache.solr.client.solrj.io.stream.expr.Explanation.ExpressionType;
import org.apache.solr.client.solrj.io.stream.expr.StreamExpression;
import org.apache.solr.client.solrj.io.stream.expr.StreamExpressionParameter;
import org.apache.solr.client.solrj.io.stream.expr.StreamExpressionValue;
import org.apache.solr.client.solrj.io.stream.expr.StreamFactory;
public abstract class ComplexEvaluator implements StreamEvaluator {
protected static final long serialVersionUID = 1L;
protected StreamContext streamContext;
protected UUID nodeId = UUID.randomUUID();
protected StreamFactory constructingFactory;
protected List<StreamEvaluator> subEvaluators = new ArrayList<StreamEvaluator>();
public ComplexEvaluator(StreamExpression expression, StreamFactory factory) throws IOException{
constructingFactory = factory;
// We have to do this because order of the parameters matter
List<StreamExpressionParameter> parameters = factory.getOperandsOfType(expression, StreamExpressionParameter.class);
for(StreamExpressionParameter parameter : parameters){
if(parameter instanceof StreamExpression){
// possible evaluator
StreamExpression streamExpression = (StreamExpression)parameter;
if(factory.doesRepresentTypes(streamExpression, ComplexEvaluator.class)){
subEvaluators.add(factory.constructEvaluator(streamExpression));
}
else if(factory.doesRepresentTypes(streamExpression, SimpleEvaluator.class)){
subEvaluators.add(factory.constructEvaluator(streamExpression));
}
else{
// Will be treated as a field name
subEvaluators.add(new FieldEvaluator(streamExpression.toString()));
}
}
else if(parameter instanceof StreamExpressionValue){
if(0 != ((StreamExpressionValue)parameter).getValue().length()){
// special case - if evaluates to a number, boolean, or null then we'll treat it
// as a RawValueEvaluator
Object value = factory.constructPrimitiveObject(((StreamExpressionValue)parameter).getValue());
if(null == value || value instanceof Boolean || value instanceof Number){
subEvaluators.add(new RawValueEvaluator(value));
}
else if(value instanceof String){
subEvaluators.add(new FieldEvaluator((String)value));
}
}
}
}
if(expression.getParameters().size() != subEvaluators.size()){
throw new IOException(String.format(Locale.ROOT,"Invalid expression %s - unknown operands found - expecting only StreamEvaluators or field names", expression));
}
}
@Override
public StreamExpressionParameter toExpression(StreamFactory factory) throws IOException {
StreamExpression expression = new StreamExpression(factory.getFunctionName(getClass()));
for(StreamEvaluator evaluator : subEvaluators){
expression.addParameter(evaluator.toExpression(factory));
}
return expression;
}
@Override
public Explanation toExplanation(StreamFactory factory) throws IOException {
return new Explanation(nodeId.toString())
.withExpressionType(ExpressionType.EVALUATOR)
.withFunctionName(factory.getFunctionName(getClass()))
.withImplementingClass(getClass().getName())
.withExpression(toExpression(factory).toString());
}
public void setStreamContext(StreamContext context) {
this.streamContext = context;
for(StreamEvaluator subEvaluator : subEvaluators){
subEvaluator.setStreamContext(context);
}
}
public StreamContext getStreamContext(){
return streamContext;
}
}