/*
* Copyright 2002-2009 the original author or authors.
*
* Licensed 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.springframework.expression.spel.ast;
import org.springframework.expression.EvaluationException;
import org.springframework.expression.TypedValue;
import org.springframework.expression.spel.ExpressionState;
import org.springframework.expression.spel.SpelEvaluationException;
import org.springframework.expression.spel.SpelMessage;
/**
* Represents a ternary expression, for example: "someCheck()?true:false".
*
* @author Andy Clement
* @author Juergen Hoeller
* @since 3.0
*/
public class Ternary extends SpelNodeImpl {
public Ternary(int pos, SpelNodeImpl... args) {
super(pos,args);
}
/**
* Evaluate the condition and if true evaluate the first alternative, otherwise evaluate the second alternative.
* @param state the expression state
* @throws EvaluationException if the condition does not evaluate correctly to a boolean or there is a problem
* executing the chosen alternative
*/
@Override
public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
Boolean value = children[0].getValue(state, Boolean.class);
if (value == null) {
throw new SpelEvaluationException(getChild(0).getStartPosition(),
SpelMessage.TYPE_CONVERSION_ERROR, "null", "boolean");
}
if (value.booleanValue()) {
return children[1].getValueInternal(state);
} else {
return children[2].getValueInternal(state);
}
}
@Override
public String toStringAST() {
return new StringBuilder().append(getChild(0).toStringAST()).append(" ? ").append(getChild(1).toStringAST())
.append(" : ").append(getChild(2).toStringAST()).toString();
}
}
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