org.tinymediamanager.scraper.http.CachedUrl.java Source code

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Here is the source code for org.tinymediamanager.scraper.http.CachedUrl.java

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/*
 * Copyright 2012 - 2016 Manuel Laggner
 *
 * 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 org.tinymediamanager.scraper.http;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URISyntaxException;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.List;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

import org.apache.commons.io.IOUtils;
import org.tinymediamanager.scraper.util.CacheMap;
import org.tinymediamanager.scraper.util.Pair;

import okhttp3.Headers;

/**
 * The class CachedUrl is used to cache some sort of Urls (e.g. when they are accessed several times in a short period)
 */
public class CachedUrl extends Url {
    private final static CacheMap<String, CachedRequest> CACHE = new CacheMap<>(600, 5);

    public CachedUrl(String url) throws MalformedURLException {
        this.url = url;
        // morph to URI to check syntax of the url
        try {
            this.uri = morphStringToUri(url);
        } catch (URISyntaxException e) {
            throw new MalformedURLException(url);
        }
    }

    @Override
    public InputStream getInputStream() throws IOException, InterruptedException {
        CachedRequest cachedRequest = CACHE.get(url);
        if (cachedRequest == null) {
            // need to fetch it with a real request
            Url url = new Url(this.url);
            url.headersRequest = headersRequest;
            InputStream is = url.getInputStream();
            if (is == null) {
                return null;
            }
            ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
            GZIPOutputStream gzip = new GZIPOutputStream(outputStream);
            IOUtils.copy(is, gzip);
            IOUtils.closeQuietly(gzip);
            IOUtils.closeQuietly(outputStream);

            // and now fill the CachedRequest object with the result
            cachedRequest = new CachedRequest(url, outputStream.toByteArray());
            if (url.responseCode >= 200 && url.responseCode < 300) {
                CACHE.put(this.url, cachedRequest);
            }
        }

        responseCode = cachedRequest.responseCode;
        responseMessage = cachedRequest.responseMessage;
        responseCharset = cachedRequest.responseCharset;
        responseContentType = cachedRequest.responseContentType;
        responseContentLength = cachedRequest.responseContentLength;

        headersResponse = cachedRequest.headersResponse;
        headersRequest.addAll(cachedRequest.headersRequest);

        return new GZIPInputStream(new ByteArrayInputStream(cachedRequest.content));
    }

    public static void clearCache() {
        CACHE.cleanup(true);
    }

    /**
     * Is the url already cached?
     * 
     * @param url
     *          the url to check
     * @return true/false
     */
    public static boolean isCached(String url) {
        return CACHE.get(url) != null;
    }

    /**
     * Is the url already cached?
     *
     * @return true/false
     */
    public boolean isCached() {
        return isCached(url);
    }

    /**
     * A inner class for representing cached entries
     */
    private static class CachedRequest {
        byte[] content;

        int responseCode = 0;
        String responseMessage = "";
        Charset responseCharset = null;
        String responseContentType = "";
        long responseContentLength = -1;

        Headers headersResponse = null;
        List<Pair<String, String>> headersRequest = new ArrayList<>();

        CachedRequest(Url url, byte[] content) {
            this.content = content;

            this.responseCode = url.responseCode;
            this.responseMessage = url.responseMessage;
            this.responseCharset = url.responseCharset;
            this.responseContentType = url.responseContentType;
            this.responseContentLength = url.responseContentLength;

            this.headersResponse = url.headersResponse;
            this.headersRequest.addAll(url.headersRequest);
        }
    }
}