ch.ralscha.extdirectspring.controller.MethodRegistrar.java Source code

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Here is the source code for ch.ralscha.extdirectspring.controller.MethodRegistrar.java

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/**
 * Copyright 2010-2016 Ralph Schaer <ralphschaer@gmail.com>
 *
 * 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 ch.ralscha.extdirectspring.controller;

import java.lang.reflect.Method;
import java.util.Set;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationListener;
import org.springframework.context.event.ContextRefreshedEvent;
import org.springframework.core.MethodIntrospector;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.stereotype.Service;
import org.springframework.util.ClassUtils;
import org.springframework.util.ReflectionUtils.MethodFilter;
import org.springframework.util.StringUtils;

import ch.ralscha.extdirectspring.annotation.ExtDirectMethod;
import ch.ralscha.extdirectspring.util.MethodInfoCache;

/**
 * Spring application listener that listens for ContextRefreshedEvent events. If such an
 * event is received the listener will scan for ExtDirectMethod annotated methods in the
 * current ApplicationContext. Found methods will be cached in the {@link MethodInfoCache}
 * . The class also reports warnings and errors of misconfigured methods.
 */
@Service
public class MethodRegistrar implements ApplicationListener<ContextRefreshedEvent>, Ordered {

    private static final Log log = LogFactory.getLog(RouterController.class);

    private final MethodInfoCache methodInfoCache;

    @Autowired
    public MethodRegistrar(MethodInfoCache methodInfoCache) {
        this.methodInfoCache = methodInfoCache;
    }

    @Override
    public void onApplicationEvent(ContextRefreshedEvent event) {

        ApplicationContext context = (ApplicationContext) event.getSource();

        String[] beanNames = context.getBeanNamesForType(Object.class);

        for (String beanName : beanNames) {

            Class<?> handlerType = context.getType(beanName);
            final Class<?> userType = ClassUtils.getUserClass(handlerType);

            Set<Method> methods = MethodIntrospector.selectMethods(userType, new MethodFilter() {
                @Override
                public boolean matches(Method method) {
                    return AnnotationUtils.findAnnotation(method, ExtDirectMethod.class) != null;
                }
            });

            for (Method method : methods) {
                ExtDirectMethod directMethodAnnotation = AnnotationUtils.findAnnotation(method,
                        ExtDirectMethod.class);
                final String beanAndMethodName = beanName + "." + method.getName();
                if (directMethodAnnotation.value().isValid(beanAndMethodName, userType, method)) {
                    this.methodInfoCache.put(beanName, handlerType, method, event.getApplicationContext());

                    // /CLOVER:OFF
                    if (log.isDebugEnabled()) {
                        String info = "Register " + beanAndMethodName + "(" + directMethodAnnotation.value();
                        if (StringUtils.hasText(directMethodAnnotation.group())) {
                            info += ", " + directMethodAnnotation.group();
                        }
                        info += ")";
                        log.debug(info);
                    }
                    // /CLOVER:ON
                }
            }

        }
    }

    @Override
    public int getOrder() {
        return Ordered.LOWEST_PRECEDENCE - 1000;
    }

}