// reading and so all of the bytes in each new allocated buffer are available for reading from
    // the stream.
    for (int bufSize = initialBufferSize;
        totalLen < MAX_ARRAY_LEN;
        bufSize = IntMath.saturatedMultiply(bufSize, bufSize < 4096 ? 4 : 2)) {
      byte[] buf = new byte[min(bufSize, MAX_ARRAY_LEN - totalLen)];
      bufs.add(buf);
      int off = 0;
      while (off < buf.length) {

 */
public abstract class InputStreamUtil {

    /**
     * Do not instantiate.
     */
    protected InputStreamUtil() {
    }

    /** Default buffer size. */
    private static final int BUF_SIZE = 4096;

    /**
     * Creates a {@link FileInputStream}.
     *
     * @param file the file (must not be {@literal null})
     * @return a {@link FileInputStream} to read from the file

 *
 * @author higa
 */
public abstract class ReaderUtil {

    /**
     * Do not instantiate.
     */
    protected ReaderUtil() {
    }

    /** Default buffer size */
    private static final int BUF_SIZE = 4096;

    /**
     * Creates a {@link Reader} to read from a file with the specified encoding.
     *
     * @param is
     *            the input stream (must not be {@literal null})
     * @param encoding

					t.Errorf("Case: %d %#v, expected: \"%s\", got: \"%s\"", i+1, testCase, string(testCase.expectedBuf), string(buf[:testCase.bufSize]))
				}
				if n != int64(testCase.bufSize) {
					t.Errorf("Case: %d %#v, expected: %d, got: %d", i+1, testCase, testCase.bufSize, n)
				}
			}
		}
	}

	// TestXLStorage for permission denied.
	if runtime.GOOS != globalWindowsOSName {

        int i = 0, n = -5;

        if (off + len > b.length) {
            throw new IOException("Buffer too short, bufsize " + b.length + " read " + len);
        }

        while (i < len) {
            n = in.read(b, off + i, len - i);
            if (n <= 0) {
                break;
            }
            i += n;
        }