/*
 * Copyright 2002-2019 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
 *
 *      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,
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 * See the License for the specific language governing permissions and
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package org.springframework.expression.spel.ast;

import org.springframework.expression.AccessException;
import org.springframework.expression.BeanResolver;
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 bean reference to a type, for example @foo or @'foo.bar'. For a FactoryBean the syntax &foo can be used to access the factory itself.
Author:Andy Clement
/** * Represents a bean reference to a type, for example <tt>@foo</tt> or <tt>@'foo.bar'</tt>. * For a FactoryBean the syntax <tt>&foo</tt> can be used to access the factory itself. * * @author Andy Clement */
public class BeanReference extends SpelNodeImpl { private static final String FACTORY_BEAN_PREFIX = "&"; private final String beanName; public BeanReference(int startPos, int endPos, String beanName) { super(startPos, endPos); this.beanName = beanName; } @Override public TypedValue getValueInternal(ExpressionState state) throws EvaluationException { BeanResolver beanResolver = state.getEvaluationContext().getBeanResolver(); if (beanResolver == null) { throw new SpelEvaluationException( getStartPosition(), SpelMessage.NO_BEAN_RESOLVER_REGISTERED, this.beanName); } try { return new TypedValue(beanResolver.resolve(state.getEvaluationContext(), this.beanName)); } catch (AccessException ex) { throw new SpelEvaluationException(getStartPosition(), ex, SpelMessage.EXCEPTION_DURING_BEAN_RESOLUTION, this.beanName, ex.getMessage()); } } @Override public String toStringAST() { StringBuilder sb = new StringBuilder(); if (!this.beanName.startsWith(FACTORY_BEAN_PREFIX)) { sb.append("@"); } if (!this.beanName.contains(".")) { sb.append(this.beanName); } else { sb.append("'").append(this.beanName).append("'"); } return sb.toString(); } }