public int readLine()

in httpcore5/src/main/java/org/apache/hc/core5/http/impl/io/SessionInputBufferImpl.java [240:291]
45 lines of code
13 McCabe index (conditional complexity)

    public int readLine(final CharArrayBuffer charBuffer, final InputStream inputStream) throws IOException {
        Args.notNull(charBuffer, "Char array buffer");
        Args.notNull(inputStream, "Input stream");
        int readLen = 0;
        boolean retry = true;
        while (retry) {
            // attempt to find end of line (LF)
            int pos = -1;
            for (int i = this.bufferPos; i < this.bufferLen; i++) {
                if (this.buffer[i] == Chars.LF) {
                    pos = i;
                    break;
                }
            }

            if (this.maxLineLen > 0) {
                final int currentLen = this.lineBuffer.length()
                        + (pos >= 0 ? pos : this.bufferLen) - this.bufferPos;
                if (currentLen >= this.maxLineLen) {
                    throw new MessageConstraintException("Maximum line length limit exceeded");
                }
            }

            if (pos != -1) {
                // end of line found.
                if (this.lineBuffer.isEmpty()) {
                    // the entire line is preset in the read buffer
                    return lineFromReadBuffer(charBuffer, pos);
                }
                retry = false;
                final int len = pos + 1 - this.bufferPos;
                this.lineBuffer.append(this.buffer, this.bufferPos, len);
                this.bufferPos = pos + 1;
            } else {
                // end of line not found
                if (hasBufferedData()) {
                    final int len = this.bufferLen - this.bufferPos;
                    this.lineBuffer.append(this.buffer, this.bufferPos, len);
                    this.bufferPos = this.bufferLen;
                }
                readLen = fillBuffer(inputStream);
                if (readLen == -1) {
                    retry = false;
                }
            }
        }
        if (readLen == -1 && this.lineBuffer.isEmpty()) {
            // indicate the end of stream
            return -1;
        }
        return lineFromLineBuffer(charBuffer);
    }