This code in src/share/classes/com/sun/tools/javadoc/DocImpl.java
makes the classic mistake of assuming that available() will return
the size of all the data that will ever be read.

    /**
     * Utility for subclasses which read HTML documentation files.
     */
    String readHTMLDocumentation(InputStream input, String filename) throws IOException {
        int filesize = input.available();
        byte[] filecontents = new byte[filesize];
        input.read(filecontents, 0, filesize);
        input.close();

No actual user-visible bug is known.