public int read()

in src/main/java/org/apache/commons/io/input/UnsynchronizedBufferedReader.java [273:324]

• 33 lines of code
• 16 McCabe index (conditional complexity)

    public int read(final char[] buffer, int offset, final int length) throws IOException {
        checkOpen();
        if (offset < 0 || offset > buffer.length - length || length < 0) {
            throw new IndexOutOfBoundsException();
        }
        int outstanding = length;
        while (outstanding > 0) {

            /*
             * If there are bytes in the buffer, grab those first.
             */
            final int available = end - pos;
            if (available > 0) {
                final int count = available >= outstanding ? outstanding : available;
                System.arraycopy(buf, pos, buffer, offset, count);
                pos += count;
                offset += count;
                outstanding -= count;
            }

            /*
             * Before attempting to read from the underlying stream, make sure we really, really want to. We won't bother if we're done, or if we've already got
             * some bytes and reading from the underlying stream would block.
             */
            if (outstanding == 0 || outstanding < length && !in.ready()) {
                break;
            }

            // assert(pos == end);

            /*
             * If we're unmarked and the requested size is greater than our buffer, read the bytes directly into the caller's buffer. We don't read into smaller
             * buffers because that could result in a many reads.
             */
            if ((mark == -1 || pos - mark >= markLimit) && outstanding >= buf.length) {
                final int count = in.read(buffer, offset, outstanding);
                if (count > 0) {
                    outstanding -= count;
                    mark = -1;
                }

                break; // assume the source stream gave us all that it could
            }

            if (fillBuf() == EOF) {
                break; // source is exhausted
            }
        }

        final int count = length - outstanding;
        return count > 0 || count == length ? count : EOF;
    }