cn.vlabs.clb.server.ui.frameservice.LocalFileCacheService.java Source code

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Here is the source code for cn.vlabs.clb.server.ui.frameservice.LocalFileCacheService.java

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/*
 * Copyright (c) 2008-2016 Computer Network Information Center (CNIC), Chinese Academy of Sciences.
 * 
 * This file is part of Duckling project.
 *
 * 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 cn.vlabs.clb.server.ui.frameservice;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;

import org.apache.commons.io.IOUtils;
import org.apache.log4j.Logger;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.stereotype.Service;

import com.mongodb.gridfs.GridFSDBFile;

@Service
public class LocalFileCacheService {
    private static final Logger LOG = Logger.getLogger(LocalFileCacheService.class);
    private Map<String, SrcPair> localFileCachedMap = new ConcurrentHashMap<String, SrcPair>();
    private CleanWorker cleanWorker = new CleanWorker();
    private static final int BUFFER_SIZE = 4096;

    public static String resizeTempDir;
    static {
        Resource tempDir = new ClassPathResource("/");
        try {
            resizeTempDir = tempDir.getFile().getPath() + File.separator + "temp" + File.separator + "resize"
                    + File.separator;
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @PostConstruct
    public void init() {
        cleanWorker.start();
        cleanWorker.setStopFlag(false);
        LOG.info("Clean file worker thread is ready to work.");
    }

    @PreDestroy
    public void destroy() {
        cleanWorker.setStopFlag(true);
        cleanWorker.interrupt();
        LOG.info("All workers are stopped.");
    }

    private File checkAndCreateTempDir() {
        File file = new File(resizeTempDir);
        if (!file.exists()) {
            file.mkdirs();
        }
        return file;
    }

    public SrcPair loadOriginalImage(GridFSDBFile gfile) {
        String srcStorageKey = gfile.get("storageKey").toString();
        SrcPair sp = saveTempFile(srcStorageKey, gfile.getInputStream());
        return sp;
    }

    public SrcPair saveTempFile(String srcStorageKey, InputStream ins) {
        long start = System.currentTimeMillis();
        checkAndCreateTempDir();
        if (localFileCachedMap.containsKey(srcStorageKey)) { // SrcPair??
            SrcPair sp = localFileCachedMap.get(srcStorageKey);
            File f = new File(sp.getSrcPath());
            if (f.exists()) {
                cleanWorker.removeJob(sp.getSrcPath());
                LOG.debug("Local file cache hit for " + srcStorageKey);
                return sp;
            } else {
                localFileCachedMap.remove(srcStorageKey);
            }
        }
        String srcPath = getTempFilename(srcStorageKey, "original");
        File srcTempFile = new File(srcPath);
        if (srcTempFile.exists() && srcTempFile.length() > 0) { // ???
            cleanWorker.removeJob(srcPath);
        } else {
            OutputStream ous = null;
            try {
                ous = new FileOutputStream(srcTempFile);
                int read = 0;
                byte buf[] = new byte[BUFFER_SIZE];
                while ((read = ins.read(buf, 0, BUFFER_SIZE)) != -1) {
                    ous.write(buf, 0, read);
                }
            } catch (IOException e1) {
                LOG.error("Write image temp file failed", e1);
                return null;
            } finally {
                IOUtils.closeQuietly(ins);
                IOUtils.closeQuietly(ous);
            }
        }
        SrcPair sp = new SrcPair();
        sp.setSrcPath(srcPath);
        sp.setSrcStorageKey(srcStorageKey);
        long end = System.currentTimeMillis();
        localFileCachedMap.put(srcStorageKey, sp);
        LOG.debug("Save temp file use time " + (end - start) + " ms");
        return sp;
    }

    public String getTempFilename(String filename, String prefix) {
        return resizeTempDir + prefix + "_" + filename;
    }

    public void addCleanJobs(String[] array) {
        for (int i = 0; i < array.length; i++) {
            cleanWorker.addNewJob(array[i]);
        }
    }

    public void removeJob(String srcPath) {
        cleanWorker.removeJob(srcPath);
    }

}