@Override
    protected StateFactory init(ExpressionExecutor[] attributeExpressionExecutors, ProcessingMode processingMode,
                                boolean outputExpectsExpiredEvents, ConfigReader configReader,
                                SiddhiQueryContext siddhiQueryContext) {
        if (attributeExpressionExecutors.length != 1) {
            throw new OperationNotSupportedException("And aggregator has to have exactly 1 parameter, currently " +
                    attributeExpressionExecutors.length
                    + " parameters provided");
        }
        return () -> new AggregatorState();
    }
The initialization method for FunctionExecutor

@param attributeExpressionExecutors are the executors of each attributes in the function
@param processingMode               query processing mode
@param outputExpectsExpiredEvents   is expired events sent as output
@param configReader                 this hold the {@link AndAttributeAggregatorExecutor} configuration reader.
@param siddhiQueryContext           current siddhi query context
modules/siddhi-core/src/main/java/io/siddhi/core/query/selector/attribute/aggregator/AndAttributeAggregatorExecutor.java