com.msopentech.odatajclient.testservice.utils.FSManager.java Source code

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Here is the source code for com.msopentech.odatajclient.testservice.utils.FSManager.java

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/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 com.msopentech.odatajclient.testservice.utils;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.EnumMap;
import java.util.Map;
import javax.ws.rs.NotFoundException;
import org.apache.commons.io.IOUtils;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSelectInfo;
import org.apache.commons.vfs2.FileSelector;
import org.apache.commons.vfs2.FileSystemException;
import org.apache.commons.vfs2.FileSystemManager;
import org.apache.commons.vfs2.VFS;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class FSManager {

    /**
     * Logger.
     */
    protected static final Logger LOG = LoggerFactory.getLogger(AbstractUtilities.class);

    private static String MEM_PREFIX = "ram://";

    private static String RES_PREFIX = "res://";

    private final FileSystemManager fsManager;

    private static Map<ODataVersion, FSManager> instance = new EnumMap<ODataVersion, FSManager>(ODataVersion.class);

    private final ODataVersion version;

    public static FSManager instance(final ODataVersion version) throws Exception {
        if (!instance.containsKey(version)) {
            instance.put(version, new FSManager(version));
        }
        return instance.get(version);
    }

    private FSManager(final ODataVersion version) throws Exception {
        this.version = version;
        fsManager = VFS.getManager();
    }

    public String getAbsolutePath(final String relativePath, final Accept accept) {
        return File.separatorChar + version.name() + File.separatorChar + relativePath
                + (accept == null ? "" : accept.getExtension());
    }

    public FileObject putInMemory(final InputStream is, final String path) throws IOException {
        final FileObject memObject = fsManager.resolveFile(MEM_PREFIX + path);

        if (memObject.exists()) {
            memObject.delete();
        }

        // create in-memory file
        memObject.createFile();

        // read in-memory content
        final OutputStream os = memObject.getContent().getOutputStream();
        IOUtils.copy(is, os);
        IOUtils.closeQuietly(is);
        IOUtils.closeQuietly(os);

        return memObject;
    }

    public InputStream readFile(final String relativePath, final Accept accept) {
        final String path = getAbsolutePath(relativePath, accept);
        LOG.info("Read {}", path);

        try {
            FileObject fileObject = fsManager.resolveFile(MEM_PREFIX + path);

            if (!fileObject.exists()) {
                LOG.warn("In-memory path '{}' not found", path);

                try {
                    fileObject = fsManager.resolveFile(RES_PREFIX + path);
                    fileObject = putInMemory(fileObject.getContent().getInputStream(), path);
                } catch (FileSystemException fse) {
                    LOG.warn("Resource path '{}' not found", path, fse);
                }
            }

            if (!fileObject.exists()) {
                throw new NotFoundException();
            }

            // return new in-memory content
            return fileObject.getContent().getInputStream();
        } catch (IOException e) {
            throw new NotFoundException(e);
        }
    }

    public void deleteFile(final String relativePath) {

        for (Accept accept : Accept.values()) {
            final String path = getAbsolutePath(relativePath, accept);
            LOG.info("Delete {}", path);

            try {
                final FileObject fileObject = fsManager.resolveFile(MEM_PREFIX + path);

                if (fileObject.exists()) {
                    fileObject.delete();
                }
            } catch (IOException ignore) {
                // ignore exception
            }
        }
    }

    public FileObject resolve(final String path) throws FileSystemException {
        FileObject res = fsManager.resolveFile(MEM_PREFIX + path);

        if (!res.exists()) {
            res = fsManager.resolveFile(RES_PREFIX + path);
        }

        if (!res.exists()) {
            throw new FileSystemException("Unresolved path " + path);
        }

        return res;
    }

    public FileObject[] findByExtension(final FileObject fo, final String ext) throws FileSystemException {
        return fo.findFiles(new FileSelector() {

            @Override
            public boolean includeFile(final FileSelectInfo fileInfo) throws Exception {
                return fileInfo.getFile().getName().getExtension().equals(ext);
            }

            @Override
            public boolean traverseDescendents(final FileSelectInfo fileInfo) throws Exception {
                return true;
            }
        });
    }
}