private void raiseException(int pos, XDDSLMessages message, Object... inserts) {
		throw new CheckpointedStreamDefinitionException(expressionString, pos, tokenStreamPointer, lastGoodPoint,
				tokenStream, message, inserts);
	}
Return the concatenation of the data of many tokens.
spring-xd-dirt/src/main/java/org/springframework/xd/dirt/stream/dsl/StreamConfigParser.java