/*
* Copyright 2012 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.data.mapping.model;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.context.expression.BeanFactoryResolver;
import org.springframework.expression.EvaluationContext;
import org.springframework.expression.ExpressionParser;
import org.springframework.expression.PropertyAccessor;
import org.springframework.expression.spel.standard.SpelExpressionParser;
import org.springframework.expression.spel.support.StandardEvaluationContext;
/**
* Simple factory to create {@link SpelExpressionParser} and {@link EvaluationContext} instances.
*
* @author Oliver Gierke
*/
public class SpELContext {
private final SpelExpressionParser parser;
private final PropertyAccessor accessor;
private final BeanFactory factory;
/**
* Creates a new {@link SpELContext} with the given {@link PropertyAccessor}. Defaults the
* {@link SpelExpressionParser}.
*
* @param accessor
*/
public SpELContext(PropertyAccessor accessor) {
this(accessor, null, null);
}
/**
* Creates a new {@link SpELContext} using the given {@link SpelExpressionParser} and {@link PropertyAccessor}. Will
* default the {@link SpelExpressionParser} in case the given value for it is {@literal null}.
*
* @param parser
* @param accessor
*/
public SpELContext(SpelExpressionParser parser, PropertyAccessor accessor) {
this(accessor, parser, null);
}
/**
* Copy constructor to create a {@link SpELContext} using the given one's {@link PropertyAccessor} and
* {@link SpelExpressionParser} as well as the given {@link BeanFactory}.
*
* @param source
* @param factory
*/
public SpELContext(SpELContext source, BeanFactory factory) {
this(source.accessor, source.parser, factory);
}
/**
* Creates a new {@link SpELContext} using the given {@link SpelExpressionParser}, {@link PropertyAccessor} and
* {@link BeanFactory}. Will default the {@link SpelExpressionParser} in case the given value for it is
* {@literal null}.
*
* @param accessor
* @param parser
* @param factory
*/
private SpELContext(PropertyAccessor accessor, SpelExpressionParser parser, BeanFactory factory) {
this.parser = parser == null ? new SpelExpressionParser() : parser;
this.accessor = accessor;
this.factory = factory;
}
/*
* (non-Javadoc)
* @see org.springframework.data.mapping.model.SpELContext#getParser()
*/
public ExpressionParser getParser() {
return this.parser;
}
/*
* (non-Javadoc)
* @see org.springframework.data.mapping.model.SpELContext#getEvaluationContext(java.lang.Object)
*/
public EvaluationContext getEvaluationContext(Object source) {
StandardEvaluationContext evaluationContext = new StandardEvaluationContext(source);
if (accessor != null) {
evaluationContext.addPropertyAccessor(accessor);
}
if (factory != null) {
evaluationContext.setBeanResolver(new BeanFactoryResolver(factory));
}
return evaluationContext;
}
}