org.chimi.s4s.storage.localfs.LocalFSFileStorage.java Source code

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Here is the source code for org.chimi.s4s.storage.localfs.LocalFSFileStorage.java

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/*
 * Copyright 2002-2011 the original author or authors.
 *
 * 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.chimi.s4s.storage.localfs;

import java.io.File;
import java.io.IOException;

import org.chimi.s4s.storage.FileData;
import org.chimi.s4s.storage.FileId;
import org.chimi.s4s.storage.FileStorage;
import org.chimi.s4s.storage.SaveFailureStorageException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.FileCopyUtils;

/**
 *  ? ? ?   FileStorage 
 * 
 * @author 
 */
public class LocalFSFileStorage implements FileStorage {
    private final Logger logger = LoggerFactory.getLogger(getClass());

    private String basePath;

    public void setBasePath(String basePath) {
        this.basePath = basePath;
    }

    @Override
    public FileId save(File file) {
        try {
            FileId id = trySaveAndGetFileId(file);
            return id;
        } catch (IOException e) {
            throw new SaveFailureStorageException(e);
        }
    }

    private FileId trySaveAndGetFileId(File file) throws IOException {
        int maxTryCount = 3;
        int tryCount = 0;
        FileId id = null;
        while (tryCount < maxTryCount) {
            tryCount++;
            try {
                id = generateFileId();
                saveFile(id, file);
                logger.warn(String.format("save file with id[%s] tryCount[%d]", id.getId(), tryCount));
                break;
            } catch (AleadySameIDFileExists ex) {
                if (tryCount == maxTryCount) {
                    throw new SaveFailureStorageException(ex);
                }
                logger.warn(String.format("fail to save file with id[%s] tryCount[%d] and retry", id.getId(),
                        tryCount));
            }
        }
        return id;
    }

    /**
     *  ? ?  ?  ? ?? .
     * <p>
     * []/yyyyMM/dd/
     * 
     * @param id
     * @param file
     * @throws IOException
     */
    private void saveFile(FileId id, File file) throws IOException {
        File dir = makeDirectory(id);
        File target = new File(dir, id.toString());
        if (target.isFile() && target.exists()) {
            throw new AleadySameIDFileExists(
                    String.format("Same ID[%s] file[%s] aleady exists.", id.getId(), target.getAbsoluteFile()));
        }
        copyFile(file, target);
    }

    private void copyFile(File file, File target) throws IOException {
        FileCopyUtils.copy(file, target);
    }

    private File makeDirectory(FileId id) {
        File dir = makeFileObjectForId(id);
        if (dir.exists()) {
            return dir;
        }
        boolean made = dir.mkdirs();
        if (!made) {
            // TODO ? ??  ? ?
            // TODO     ? 
        }
        return dir;
    }

    private File makeFileObjectForId(FileId id) {
        File dir = new File(basePath, FilePathUtil.getDirectoryPath(id));
        return dir;
    }

    /**
     * ? ID ? ? ?.
     * <p>
     * yyyyMMddHHmmssNNNNNNNN
     * <p>
     * yyyy-?. MM-. dd-. HH-24. mm-. ss-. [NNNNNNNN]? ? 16 8? ?.
     * 
     * @return
     */
    private FileId generateFileId() {
        return LocalFSFileIdUtil.generateFileId();
    }

    @Override
    public FileData find(FileId id) {
        File dir = makeFileObjectForId(id);
        File file = new File(dir, id.getId());
        if (!file.exists()) {
            return null;
        }
        return new LocalFSFileData(id, file);
    }

}