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

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

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/**
 * Copyright 2010-2013 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.util.Locale;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.util.WebUtils;

import ch.ralscha.extdirectspring.bean.SSEvent;
import ch.ralscha.extdirectspring.util.ExtDirectSpringUtil;
import ch.ralscha.extdirectspring.util.MethodInfo;
import ch.ralscha.extdirectspring.util.MethodInfoCache;

@Service
public class SSEHandler {

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

    @Autowired
    private ConfigurationService configurationService;

    public void handle(String beanName, String method, HttpServletRequest request, HttpServletResponse response,
            Locale locale) throws Exception {

        MethodInfo methodInfo = MethodInfoCache.INSTANCE.get(beanName, method);

        SSEvent result = null;
        SSEWriter sseWriter = new SSEWriter(response);

        if (methodInfo != null) {

            try {

                Object[] parameters = configurationService.getParametersResolver().prepareParameters(request,
                        response, locale, methodInfo, sseWriter);
                Object methodReturnValue = null;

                if (configurationService.getConfiguration().isSynchronizeOnSession()
                        || methodInfo.isSynchronizeOnSession()) {
                    HttpSession session = request.getSession(false);
                    if (session != null) {
                        Object mutex = WebUtils.getSessionMutex(session);
                        synchronized (mutex) {
                            methodReturnValue = ExtDirectSpringUtil.invoke(
                                    configurationService.getApplicationContext(), beanName, methodInfo, parameters);
                        }
                    } else {
                        methodReturnValue = ExtDirectSpringUtil.invoke(configurationService.getApplicationContext(),
                                beanName, methodInfo, parameters);
                    }
                } else {
                    methodReturnValue = ExtDirectSpringUtil.invoke(configurationService.getApplicationContext(),
                            beanName, methodInfo, parameters);
                }

                if (methodReturnValue instanceof SSEvent) {
                    result = (SSEvent) methodReturnValue;
                } else if (methodReturnValue != null) {
                    result = new SSEvent();
                    result.setData(methodReturnValue.toString());
                }

            } catch (Exception e) {
                log.error("Error polling method '" + beanName + "." + method + "'",
                        e.getCause() != null ? e.getCause() : e);

                Throwable cause;
                if (e.getCause() != null) {
                    cause = e.getCause();
                } else {
                    cause = e;
                }

                result = new SSEvent();
                result.setEvent("error");
                result.setData(configurationService.getConfiguration().getMessage(cause));

                if (configurationService.getConfiguration().isSendStacktrace()) {
                    result.setComment(ExtDirectSpringUtil.getStackTrace(cause));
                }
            }
        } else {
            log.error("Error invoking method '" + beanName + "." + method + "'. Method or Bean not found");

            result = new SSEvent();
            result.setEvent("error");
            result.setData(configurationService.getConfiguration().getDefaultExceptionMessage());

            if (configurationService.getConfiguration().isSendStacktrace()) {
                result.setComment("Bean or Method '" + beanName + "." + method + "' not found");
            }
        }

        if (result != null) {
            sseWriter.write(result);
        }
    }

}