package org.infinispan.objectfilter.impl.aggregation;
/**
* An accumulator that returns the smallest of the values it encounters. Values must be {@link Comparable}. The return
* has the same type as the field to which it is applied. {@code Null} values are ignored. If there are no remaining
* non-null values to compute then the result of the aggregate function is {@code null}.
*
* @author anistor@redhat.com
* @since 8.0
*/
final class MinAccumulator extends FieldAccumulator {
MinAccumulator(int inPos, int outPos, Class<?> fieldType) {
super(inPos, outPos);
if (!Comparable.class.isAssignableFrom(fieldType)) {
throw new IllegalStateException("Aggregation MIN cannot be applied to property of type " + fieldType.getName());
}
}
@Override
public void update(Object[] accRow, Object value) {
if (value != null) {
Comparable min = (Comparable) accRow[outPos];
if (min == null || min.compareTo(value) > 0) {
accRow[outPos] = value;
}
}
}
}