WrappedResponseInputStream extends InputStream { @Override public int available() throws IOException { return delegate.available(); } WrappedResponseInputStream(
            @NonNull InputStream delegate, @NonNull Response delegateResponse); @Override int read(); @Override int read(final byte b[]); @Override int read(final byte b[], final int off, final int len); @Override long skip(final long n); @Override synchronized void mark(int readlimit); @Override synchronized void reset(); @Override int available(); @Override boolean markSupported(); @Override void close();  }
@Test public void available_withDelegateInputStream_shouldAvailableFromDelegate() throws Exception { final WrappedResponseInputStream streamUnderTest = new WrappedResponseInputStream(mockDelegateStream, mockRawResponseDelegate); streamUnderTest.available(); verify(mockDelegateStream).available(); }