/** デフォルトのバッファサイズ */
    private static final int BUF_SIZE = 4096;

    /**
     * {@link FileInputStream}を作成します。
     *
     * @param file
     *            ファイル。{@literal null}であってはいけません
     * @return ファイルから入力する{@link FileInputStream}
     * @see FileInputStream#FileInputStream(File)
     */
    public static FileInputStream create(final File file) {
        assertArgumentNotNull("file", file);

        try {

import static org.codelibs.core.misc.AssertionUtil.assertArgumentNotEmpty;
import static org.codelibs.core.misc.AssertionUtil.assertArgumentNotNull;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.net.URL;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;

import static org.codelibs.core.misc.AssertionUtil.assertArgumentNotEmpty;
import static org.codelibs.core.misc.AssertionUtil.assertArgumentNotNull;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;

import org.codelibs.core.exception.IORuntimeException;

/**

        assertArgumentNotNull("in", in);
        assertArgumentNotNull("out", out);

        if (in instanceof FileInputStream) {
            if (out instanceof FileOutputStream) {
                return copyInternal((FileInputStream) in, (FileOutputStream) out);
            }
            return copyInternal((FileInputStream) in, wrap(out));
        }
        if (out instanceof FileOutputStream) {

            return false;
        }

        return true;
    }

    public synchronized void load() {
        final Properties prop = new Properties();
        try (final FileInputStream fis = new FileInputStream(propertiesFile)) {
            lastModified = propertiesFile.lastModified();
            prop.load(fis);
        } catch (final IOException e) {
            throw new IORuntimeException(e);
        }