public Builder elementId(final String elementId) {
            this.elementId = elementId;
            return this;
        }
Reads characters into an array.  This method will block until some input
is available, an I/O error occurs, or the end of the stream is reached.

@param cbuf Destination buffer
@return The number of characters read, or -1
if the end of the stream
has been reached
@throws IOException If an I/O error occurs
stroom-pipeline/src/main/java/stroom/pipeline/reader/FindReplaceFilter.java