com.genericconf.bbbgateway.services.ApiCallExecution.java Source code

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Here is the source code for com.genericconf.bbbgateway.services.ApiCallExecution.java

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/**
 * Copyright 2010 Generic Conferencing, LLC
 *
 * 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 com.genericconf.bbbgateway.services;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Map;

import org.apache.http.client.HttpClient;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.BasicResponseHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.genericconf.bbbgateway.domain.ApiException;
import com.genericconf.bbbgateway.domain.Attendee;
import com.genericconf.bbbgateway.domain.Role;
import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.converters.collections.CollectionConverter;
import com.thoughtworks.xstream.io.xml.DomDriver;
import com.thoughtworks.xstream.mapper.ClassAliasingMapper;
import com.thoughtworks.xstream.mapper.MapperWrapper;

public abstract class ApiCallExecution {

    private static final Logger logger = LoggerFactory.getLogger(ApiCallExecution.class);

    public static final XStream XSTREAM;

    static {
        final XStream xs = new XStream(new DomDriver()) {
            @Override
            protected MapperWrapper wrapMapper(final MapperWrapper next) {
                return new MapperWrapper(next) {
                    @SuppressWarnings("unchecked")
                    @Override
                    public Class realClass(String elementName) {
                        final ClassAliasingMapper cam = (ClassAliasingMapper) next
                                .lookupMapperOfType(ClassAliasingMapper.class);
                        final boolean found = cam.aliasIsAttribute(elementName);
                        return found ? super.realClass(elementName) : String.class;
                    }

                };
            }
        };
        xs.registerConverter(new MapEntryConverter(xs));
        xs.registerConverter(new CollectionConverter(xs.getMapper()));
        xs.registerConverter(new IntegerConverter());
        xs.registerConverter(new DateConverter(new SimpleDateFormat("EEE MMM dd HH:mm:ss z yyyy")));
        xs.alias("response", Map.class);
        xs.alias("attendees", List.class);
        xs.addImplicitCollection(Map.class, "attendees");
        xs.alias("attendee", Attendee.class);
        xs.aliasField("fullName", Attendee.class, "name");
        xs.alias("role", Role.class);
        xs.alias("running", Boolean.class);
        xs.alias("participantCount", Integer.class);
        xs.alias("moderatorCount", Integer.class);
        xs.alias("startTime", Date.class);
        xs.alias("endTime", Date.class);
        XSTREAM = xs;
    }

    final boolean execute() throws ApiException {
        try {
            return doExecute();
        } catch (Exception e) {
            if (e instanceof ApiException) {
                throw (ApiException) e;
            }
            // wrap:
            throw new ApiException("error calling BigBlueButton API: " + e.getMessage(), e);
        }

    }

    @SuppressWarnings("unchecked")
    final Map<String, Object> getXmlFromApi(HttpClient httpClient, String url) throws Exception {
        CharSequence rawxml = makeHttpRequest(httpClient, url);
        Map<String, Object> xml = (Map<String, Object>) XSTREAM.fromXML(rawxml.toString());
        if (!wasSuccess(xml)) {
            logger.error("Call was unsuccessful.  Here is the XML:\n" + xml);
        }
        return xml;
    }

    final boolean wasSuccess(Map<String, Object> response) {
        return "SUCCESS".equals(response.get("returncode"));
    }

    final CharSequence makeHttpRequest(HttpClient httpClient, String url) throws Exception {
        HttpGet httpget = new HttpGet(url);
        logger.info("executing request " + httpget.getURI());
        // Create a response handler
        ResponseHandler<String> responseHandler = new BasicResponseHandler();
        String responseBody = httpClient.execute(httpget, responseHandler);
        logger.debug("Response: " + responseBody);
        return responseBody;
    }

    abstract boolean doExecute() throws Exception;

}