public int readFrom()

in src/main/java/org/apache/commons/text/StrBuilder.java [2423:2451]


    public int readFrom(final Readable readable) throws IOException {
        final int oldSize = size;
        if (readable instanceof Reader) {
            final Reader r = (Reader) readable;
            ensureCapacity(size + 1);
            int read;
            while ((read = r.read(buffer, size, buffer.length - size)) != -1) {
                size += read;
                ensureCapacity(size + 1);
            }
        } else if (readable instanceof CharBuffer) {
            final CharBuffer cb = (CharBuffer) readable;
            final int remaining = cb.remaining();
            ensureCapacity(size + remaining);
            cb.get(buffer, size, remaining);
            size += remaining;
        } else {
            while (true) {
                ensureCapacity(size + 1);
                final CharBuffer buf = CharBuffer.wrap(buffer, size, buffer.length - size);
                final int read = readable.read(buf);
                if (read == -1) {
                    break;
                }
                size += read;
            }
        }
        return size - oldSize;
    }