com.redhat.lightblue.eval.ArrayRangeProjector Maven / Gradle / Ivy
/*
Copyright 2013 Red Hat, Inc. and/or its affiliates.
This file is part of lightblue.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see .
*/
package com.redhat.lightblue.eval;
import com.redhat.lightblue.util.Path;
import com.redhat.lightblue.metadata.FieldTreeNode;
import com.redhat.lightblue.query.ArrayRangeProjection;
/**
* Projector that returns a range of elements from an array
*/
public class ArrayRangeProjector extends ArrayProjector {
private final int from;
private final int to;
/**
* Ctor
*
* @param p The projection expression
* @param ctxPath The absolute path relative to which this is to be
* interpreted
* @param context The metadata node at which this is to be interpreted
*/
public ArrayRangeProjector(ArrayRangeProjection p, Path ctxPath, FieldTreeNode ctx) {
super(p, ctxPath, ctx);
from = p.getFrom();
to = p.getTo();
}
@Override
protected Boolean projectArray(Path p, QueryEvaluationContext ctx) {
// Is this array element in range?
int index = p.getIndex(p.numSegments() - 1);
if (index >= from && index <= to) {
// This array element is selected.
setLastMatch(true);
return isIncluded() ? Boolean.TRUE : Boolean.FALSE;
} else {
return Boolean.FALSE;
}
}
}