io.questdb.cairo.BitmapIndexFwdNullReader Maven / Gradle / Ivy
/*******************************************************************************
* ___ _ ____ ____
* / _ \ _ _ ___ ___| |_| _ \| __ )
* | | | | | | |/ _ \/ __| __| | | | _ \
* | |_| | |_| | __/\__ \ |_| |_| | |_) |
* \__\_\\__,_|\___||___/\__|____/|____/
*
* Copyright (c) 2014-2019 Appsicle
* Copyright (c) 2019-2020 QuestDB
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
******************************************************************************/
package io.questdb.cairo;
import io.questdb.cairo.sql.RowCursor;
public class BitmapIndexFwdNullReader implements BitmapIndexReader {
private final NullCursor cursor = new NullCursor();
@Override
public RowCursor getCursor(boolean cachedInstance, int key, long minValue, long maxValue) {
final NullCursor cursor = getCursor(cachedInstance);
cursor.max = maxValue + 1;
cursor.value = 0;
return cursor;
}
@Override
public int getKeyCount() {
return 1;
}
@Override
public boolean isOpen() {
return true;
}
private NullCursor getCursor(boolean cachedInstance) {
return cachedInstance ? cursor : new NullCursor();
}
private static class NullCursor implements RowCursor {
private long max;
private long value;
@Override
public boolean hasNext() {
return value < max;
}
@Override
public long next() {
return value++;
}
}
}