org.openddr.simpleapi.oddr.identificator.CachedBrowserIdentificator.java Source code

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Here is the source code for org.openddr.simpleapi.oddr.identificator.CachedBrowserIdentificator.java

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/**
 * Copyright 2012 Fundacin CTIC
 * This software is distributed under the terms of the GNU Lesser General Public License.
 *
 *
 * This file is part of OpenDDR Simple APIs.
 * OpenDDR Simple APIs is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, version 3 of the License.
 *
 * OpenDDR Simple APIs is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Simple APIs.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author Jos Quiroga ?lvarez
 * @author Diego Martnez Ballesteros
 *
 */
package org.openddr.simpleapi.oddr.identificator;

import java.util.Map;

import org.apache.commons.collections.map.LRUMap;
import org.openddr.simpleapi.oddr.builder.Builder;
import org.openddr.simpleapi.oddr.model.UserAgent;
import org.openddr.simpleapi.oddr.model.UserAgentFactory;
import org.openddr.simpleapi.oddr.model.browser.Browser;
import org.w3c.ddr.simple.Evidence;

public class CachedBrowserIdentificator extends BrowserIdentificator implements CachedIdentificator {

    // caches
    private LRUMap browserCache;
    private LRUMap notFoundUA;

    public CachedBrowserIdentificator(Builder[] builders, Map<String, Browser> browserCapabilities,
            Integer maxCacheSize, Integer maxNotFoundUASize) {
        super(builders, browserCapabilities);
        browserCache = new LRUMap(maxCacheSize);
        notFoundUA = new LRUMap(maxNotFoundUASize);
    }

    public Browser get(String userAgent, int confidenceTreshold) {
        return get(UserAgentFactory.newUserAgent(userAgent), confidenceTreshold);
    }

    // XXX to be refined, this should NOT be the main entry point, we should use
    // a set of evidence derivation
    public Browser get(Evidence evdnc, int threshold) {
        UserAgent ua = UserAgentFactory.newBrowserUserAgent(evdnc);

        if (ua != null) {
            return get(ua, threshold);
        }

        return null;
    }

    @Override
    public Browser get(UserAgent userAgent, int confidenceTreshold) {
        // check if the device is in the cache
        Browser foundBrowser = (Browser) getFromCache(userAgent);

        if (foundBrowser == null) {
            if (isUaNotFound(userAgent)) {
                return null;
            }
            for (Builder builder : builders) {
                if (builder.canBuild(userAgent)) {
                    Browser browser = (Browser) builder.build(userAgent, confidenceTreshold);
                    if (browser != null) {
                        if (browserCapabilities != null) {
                            String bestID = getClosestKnownBrowserID(browser.getId());
                            if (bestID != null) {
                                browser.putPropertiesMap(browserCapabilities.get(bestID).getPropertiesMap());
                                if (!bestID.equals(browser.getId())) {
                                    browser.setConfidence(browser.getConfidence() - 15);
                                }
                            }
                        }
                        // add browser to the cache
                        addToCache(userAgent, browser);
                        return browser;
                    }
                }
            }
        } else {
            return foundBrowser;
        }
        addNotFoundUa(userAgent);
        return null;
    }

    public Boolean isUaNotFound(UserAgent userAgent) {
        if (notFoundUA.get(userAgent.getCompleteUserAgent()) != null) {
            return true;
        }
        return false;
    }

    @Override
    public void addNotFoundUa(UserAgent userAgent) {
        notFoundUA.put(userAgent.getCompleteUserAgent(), false);
    }

    @Override
    public Object getFromCache(UserAgent userAgent) {
        Browser cachedBrowser = (Browser) browserCache.get(userAgent.getCompleteUserAgent());
        if (cachedBrowser == null) {
            return null;
        }
        return cachedBrowser;
    }

    @Override
    public void addToCache(UserAgent userAgent, Object browser) {
        browserCache.put(userAgent.getCompleteUserAgent(), browser);

    }
}