Method isEmpty

output/java_guava/1.4.17/ByteSource.java:150–164

Returns whether the source has zero bytes. The default implementation returns true if #sizeIfKnown returns zero, falling back to opening a stream and checking for EOF if the size is not known. Note that, in cases where sizeIfKnown returns zero, it is possible that bytes ar

()

  public boolean isEmpty() throws IOException {
    Optional<Long> sizeIfKnown = sizeIfKnown();
    if (sizeIfKnown.isPresent() && sizeIfKnown.get() == 0L) {
      return true;
    }
    Closer closer = Closer.create();
    try {
      InputStream in = closer.register(openStream());
      return in.read() == -1;
    } catch (Throwable e) {
      throw closer.rethrow(e);
    } finally {
      closer.close();
    }
  }

  /**
   * Returns the size of this source in bytes, if the size can be easily determined without actually