eu.scape_project.pit.util.FileUtils.java Source code

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Here is the source code for eu.scape_project.pit.util.FileUtils.java

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/*
 * Copyright ${global_year} The ${global_project_prefix} Project Consortium
 *
 *   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 eu.scape_project.pit.util;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Some file utilities used by the client and service.
 *
 * @author ${global_project_prefix} Project Consortium
 * @version ${global_wrapper_version}
 */
public final class FileUtils {

    /** Path to the Java System temp directory */
    public static final String JAVA_TMP = System.getProperty("java.io.tmpdir");
    private static final String TMP_DIR = "${project_midfix_lc}-tmp-store";
    private static Logger logger = LoggerFactory.getLogger(FileUtils.class.getName());

    /**
     * Empty private constructor avoids instantiation.
     */
    private FileUtils() {
    }

    /**
     * @param inputUrl
     * @return the file name derived from the URL
     */
    public static String getFileNameFromUrl(URL inputUrl) {
        String urlStr = inputUrl.toString();
        String fileName = urlStr.substring(urlStr.lastIndexOf("/") + 1);
        return fileName;
    }

    /**
     * Get system's JAVA temporary directory.
     * @return System's JAVA temporary directory
     */
    public static File getSystemTempFolder() {
        return new File(JAVA_TMP);
    }

    /**
     * Get temporary file
     * @param name File name
     * @param suffix Suffix
     * @return Temp file folder
     */
    public static File getTmpFile(final String name, final String suffix) {
        String suffixToUse = suffix == null ? ".tmp" : suffix;
        if (!suffixToUse.startsWith(".")) {
            suffixToUse = "." + suffix;
        }
        String nameToUse = name == null ? "tmp" : name;
        File input = null;
        try {
            File folder = new File(JAVA_TMP, FileUtils.TMP_DIR);
            if (!folder.exists()) {
                boolean mkdirs = folder.mkdirs();
                checkCreation(folder, mkdirs);
            }
            input = File.createTempFile(nameToUse, suffixToUse, folder);
            input.deleteOnExit();
        } catch (IOException e) {
            logger.error("An error occurred while creating the temporary file: \"" + name + suffix + "\"");
        }
        return input;
    }

    /**
     * @param folder The file we tried to create
     * @param mkdirs The result of creating the file
     */
    private static void checkCreation(final File folder, final boolean mkdirs) {
        logger.info(String.format("Created folder '%s': %s", folder, mkdirs));
        if (!folder.exists()) {
            throw new IllegalArgumentException(String.format("Could not create '%s'", folder));
        }
    }

    /**
     * Read file of URL into file.
     * @param url URL where the input file is located
     * @param ext 
     * @return Result file
     * @throws IOException 
     */
    public static File urlToFile(URL url, String ext) throws IOException {
        File fOut = null;

        fOut = getTmpFile("fromurl", "." + ext);

        URLConnection uc = url.openConnection();
        logger.info("ContentType: " + uc.getContentType());
        InputStream in = uc.getInputStream();
        org.apache.commons.io.FileUtils.copyInputStreamToFile(in, fOut);
        logger.info("File of length " + fOut.length() + " created from URL " + url.toString());

        in.close();

        return fOut;
    }

}