001/**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.camel.language.spel;
018
019import org.apache.camel.Expression;
020import org.apache.camel.Predicate;
021import org.apache.camel.Service;
022import org.apache.camel.spi.annotations.Language;
023import org.apache.camel.spring.SpringCamelContext;
024import org.apache.camel.spring.util.RegistryBeanResolver;
025import org.apache.camel.support.LanguageSupport;
026import org.apache.camel.util.ObjectHelper;
027import org.springframework.context.ApplicationContext;
028import org.springframework.context.expression.BeanFactoryResolver;
029import org.springframework.expression.BeanResolver;
030
031/**
032 * A Spring Expression {@link org.apache.camel.spi.Language} plugin
033 */
034@Language("spel")
035public class SpelLanguage extends LanguageSupport implements Service {
036
037    private BeanResolver beanResolver;
038
039    public Predicate createPredicate(String expression) {
040        expression = loadResource(expression);
041        return new SpelExpression(expression, Boolean.class, beanResolver);
042    }
043
044    public Expression createExpression(String expression) {
045        expression = loadResource(expression);
046        return new SpelExpression(expression, Object.class, beanResolver);
047    }
048
049    @Override
050    public void start() throws Exception {
051        ObjectHelper.notNull(getCamelContext(), "CamelContext", this);
052
053        if (getCamelContext() instanceof SpringCamelContext) {
054            ApplicationContext applicationContext = ((SpringCamelContext) getCamelContext()).getApplicationContext();
055            beanResolver = new BeanFactoryResolver(applicationContext);
056        } else {
057            beanResolver = new RegistryBeanResolver(getCamelContext().getRegistry());
058        }
059    }
060
061    @Override
062    public void stop() throws Exception {
063        // noop
064    }
065}