fm.last.moji.local.LocalFileSystemMoji.java Source code

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Here is the source code for fm.last.moji.local.LocalFileSystemMoji.java

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/*
 * Copyright 2012 Last.fm
 *
 *  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 fm.last.moji.local;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import org.apache.commons.io.FileUtils;

import fm.last.moji.Moji;
import fm.last.moji.MojiDeviceStatus;
import fm.last.moji.MojiFile;

/**
 * A simple {@link fm.last.moji.Moji Moji} implementation that uses the local filesystem for storage. This is intended
 * for testing only.
 */
public class LocalFileSystemMoji implements Moji {

    private final File baseFolder;
    private final LocalFileNamingStrategy namingStrategy;
    private final String domain;

    public LocalFileSystemMoji(File baseFolder, String domain) {
        this(baseFolder, domain, new Base64FileNamingStrategy(baseFolder));
    }

    public LocalFileSystemMoji(File baseFolder, String domain, LocalFileNamingStrategy namingStrategy) {
        createBaseFolderIfNeeded(baseFolder);
        this.baseFolder = baseFolder;
        this.domain = domain;
        this.namingStrategy = namingStrategy;
    }

    public File getBaseFolder() {
        return baseFolder;
    }

    public LocalFileNamingStrategy getNamingStrategy() {
        return namingStrategy;
    }

    public String getDomain() {
        return domain;
    }

    @Override
    public MojiFile getFile(String key) {
        return new LocalMojiFile(namingStrategy, baseFolder, domain, key);
    }

    @Override
    public MojiFile getFile(String key, String storageClass) {
        return new LocalMojiFile(namingStrategy, baseFolder, domain, key, storageClass);
    }

    @Override
    public void copyToMogile(File source, MojiFile destination) throws IOException {
        LocalMojiFile localDestination = (LocalMojiFile) destination;
        FileUtils.copyFile(source, localDestination.file);
    }

    @Override
    public List<MojiFile> list(final String keyPrefix) {
        File[] files = baseFolder.listFiles(namingStrategy.filterForPrefix(domain, keyPrefix));
        List<MojiFile> mojiFiles = new ArrayList<MojiFile>(files.length);
        for (File file : files) {
            String key = namingStrategy.keyForFileName(file.getName());
            String storageClass = namingStrategy.storageClassForFileName(file.getName());
            mojiFiles.add(new LocalMojiFile(namingStrategy, baseFolder, domain, key, storageClass));
        }
        return mojiFiles;
    }

    @Override
    public List<MojiFile> list(String keyPrefix, int limit) {
        List<MojiFile> list = list(keyPrefix);
        int count = limit > list.size() ? list.size() : limit;
        List<MojiFile> mojiFiles = new ArrayList<MojiFile>();
        for (int i = 0; i < count; i++) {
            mojiFiles.add(list.get(i));
        }
        return mojiFiles;
    }

    /**
     * Always returns an empty list.
     */
    @Override
    public List<MojiDeviceStatus> getDeviceStatuses() {
        return Collections.emptyList();
    }

    @Override
    public String toString() {
        StringBuilder builder = new StringBuilder();
        builder.append("LocalFileSystemMoji [baseFolder=");
        builder.append(baseFolder);
        builder.append(", domain=");
        builder.append(domain);
        builder.append(", namingStrategy=");
        builder.append(namingStrategy);
        builder.append("]");
        return builder.toString();
    }

    private void createBaseFolderIfNeeded(File baseFolder) {
        boolean exists = baseFolder.exists();
        if (!exists) {
            boolean mkdirs = baseFolder.mkdirs();
            if (!mkdirs) {
                throw new IllegalStateException("Could not create base directory: " + baseFolder.getAbsolutePath());
            }
        }
    }

}