On Fri, 2 Jul 2021 17:40:08 GMT, Brian Burkhalter <bpb@openjdk.org> wrote:
src/java.base/share/classes/java/io/ByteArrayInputStream.java line 161:
159: * Unlike the {@link InputStream#read(byte[],int,int) overridden method} 160: * of {@code InputStream}, this method returns {@code -1} instead of zero 161: * if the end of the stream has been reached and {@code len == 0}.
The statement "return -1 if the end of the stream has been reached and len == 0" gives an impression that it requires both conditions to be met: end of the stream && len==0, but the tests show -1 is expected if len == 0 without an attempt to read the stream.
The overridden method stated that "If len is zero, then no bytes are read and 0 is returned", the above note looks like was meant for this statement since the overridden method also return -1 if the stream is at end of file.
Both conditions of the statement are intended to be met. If the stream is at its end then
if (pos >= count) { return -1; }
will cause `-1` to be returned because at end of stream the condition `pos >= count` is met.
The overridden method always returns `0` if `len == 0`.:
public int read(byte b[], int off, int len) throws IOException { Objects.checkFromIndexSize(off, len, b.length); if (len == 0) { return 0; }
Right. I understand. The intention was, unlike the overridden method that returns 0 if len == 0 and -1 if at the end of the stream, this method returns -1 in both cases. A careful reader, after comparing both methods, would understand correctly that the difference is in the case of "len==0". I'm fine if you think this is good enough. Just a thought though that the statement could be interpreted as if both conditions need to be met at the same time (if "and" is taken as "&&", e.g. if (pos>==count && len==0) ). Something like the following might be clearer? * Unlike the {@link InputStream#read(byte[],int,int) overridden method} * of {@code InputStream} that returns {@code -1} if the end of the stream * has been reached and {@code 0} if {@code len == 0}, this method returns * {@code -1} in both cases. Just my 2 cents. ------------- PR: https://git.openjdk.java.net/jdk17/pull/189