content: /*****************************************************************
   *   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
   *
   *    https://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.cayenne.exp.parser;
  
  import java.util.function.Function;
  
  import org.apache.cayenne.exp.Expression;
  
  /**
   * "In" expression.
   * 
   */
  public class ASTIn extends ConditionNode {
  
  	private static final long serialVersionUID = -211084571117172965L;
  
  	/**
  	 * Constructor used by expression parser. Do not invoke directly.
  	 */
  	ASTIn(int id) {
  		super(id);
  	}
  
  	public ASTIn() {
  		super(ExpressionParserTreeConstants.JJTIN);
  	}
  
  	public ASTIn(SimpleNode path, SimpleNode node) {
  		super(ExpressionParserTreeConstants.JJTIN);
  		jjtAddChild(path, 0);
  		jjtAddChild(node, 1);
  		connectChildren();
  	}
  
  	@Override
  	protected int getRequiredChildrenCount() {
  		return 2;
  	}
  
  	@Override
  	protected Boolean evaluateSubNode(Object o, Object[] evaluatedChildren) throws Exception {
  		if (o == null || evaluatedChildren[1] == null) {
  			// Even if there is NULL value in list we should return false,
  			// as check against NULL can be done only with IS NULL operator
  			// and moreover not all DB accept syntax like 'value IN (NULL)'
  			return Boolean.FALSE;
  		}
  
  		Object[] objects = (Object[]) evaluatedChildren[1];
  		for (Object object : objects) {
  			if (object != null && Evaluator.evaluator(o).eq(o, object)) {
  				return Boolean.TRUE;
  			}
  		}
  
  		return Boolean.FALSE;
  	}
  
  	/**
  	 * Creates a copy of this expression node, without copying children.
  	 */
  	@Override
  	public Expression shallowCopy() {
  		return new ASTIn(id);
  	}
  
  	@Override
  	protected String getExpressionOperator(int index) {
  		return "in";
  	}
  
  	@Override
  	public int getType() {
  		return Expression.IN;
  	}
  
  	@Override
  	protected Object transformExpression(Function<Object, Object> transformer) {
  		Object transformed = super.transformExpression(transformer);
  
  		// transform empty ASTIn to ASTFalse
  		if (transformed instanceof ASTIn) {
  			ASTIn exp = (ASTIn) transformed;
  			if (exp.jjtGetNumChildren() == 2) {
  				Node child = exp.jjtGetChild(1);
  				if(child instanceof ASTList) {
  					ASTList list = (ASTList) child;
  					Object[] objects = (Object[]) list.evaluate(null);
  					if (objects.length == 0) {
  						transformed = new ASTFalse();
  					}
  				}
  			}
  		}
  
  		return transformed;
  	}
  
  }
  