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* 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
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* KIND, either express or implied. See the License for the
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package org.apache.cayenne.exp.parser;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
/**
* @since 4.0
*/
public abstract class EvaluatedNode extends SimpleNode {
protected EvaluatedNode(int i) {
super(i);
}
@Override
protected Object evaluateNode(Object o) throws Exception {
int len = jjtGetNumChildren();
int requiredLen = getRequiredChildrenCount();
if (len < requiredLen) {
return null;
}
if(requiredLen == 0) {
return evaluateSubNode(null, null);
}
final Object[] evaluatedChildren = new Object[len];
for(int i=0; i<len; i++) {
evaluatedChildren[i] = evaluateChild(i, o);
}
Object firstChild = evaluatedChildren[0];
// convert Map, keep Map keys
if(firstChild instanceof Map) {
@SuppressWarnings("unchecked")
Map<Object, Object> child = (Map<Object, Object>) firstChild;
Map<Object, Object> result = new HashMap<>(child.size());
for(Map.Entry<Object, Object> entry : child.entrySet()) {
result.put(entry.getKey(), evaluateSubNode(entry.getValue(), evaluatedChildren));
}
return result;
}
// convert collection
if (firstChild instanceof Collection) {
@SuppressWarnings("unchecked")
Collection<Object> child = (Collection<Object>) firstChild;
Collection<Object> result = new ArrayList<>(child.size());
for(Object c : child) {
result.add(evaluateSubNode(c, evaluatedChildren));
}
return result;
}
// convert scalar
return evaluateSubNode(firstChild, evaluatedChildren);
}
abstract protected int getRequiredChildrenCount();
abstract protected Object evaluateSubNode(Object o, Object[] evaluatedChildren) throws Exception;
}