io.questdb.cairo.SymbolColumnIndexer 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.std.Misc;
import io.questdb.std.Unsafe;
import io.questdb.std.str.Path;
import java.io.Closeable;
class SymbolColumnIndexer implements ColumnIndexer, Closeable {
private static final long SEQUENCE_OFFSET;
static {
SEQUENCE_OFFSET = Unsafe.getFieldOffset(SymbolColumnIndexer.class, "sequence");
}
private final BitmapIndexWriter writer = new BitmapIndexWriter();
private final SlidingWindowMemory mem = new SlidingWindowMemory();
private long columnTop;
@SuppressWarnings({"unused", "FieldCanBeLocal"})
private volatile long sequence = 0L;
private volatile boolean distressed = false;
@Override
public void close() {
Misc.free(writer);
Misc.free(mem);
}
@Override
public void distress() {
distressed = true;
}
@Override
public long getFd() {
return mem.getFd();
}
@Override
public long getSequence() {
return sequence;
}
@Override
public void index(long loRow, long hiRow) {
mem.updateSize();
// while we may have to read column starting with zero offset
// index values have to be adjusted to partition-level row id
for (long lo = loRow - columnTop; lo < hiRow; lo++) {
writer.add(TableUtils.toIndexKey(mem.getInt(lo * 4)), lo + columnTop);
}
}
@Override
public boolean isDistressed() {
return distressed;
}
@Override
public void of(CairoConfiguration configuration, Path path, CharSequence name, AppendMemory mem1, long columnTop) {
this.columnTop = columnTop;
try {
this.writer.of(configuration, path, name);
this.mem.of(mem1);
} catch (CairoException e) {
this.close();
throw e;
}
}
@Override
public void rollback(long maxRow) {
this.writer.rollbackValues(maxRow);
}
@Override
public boolean tryLock(long expectedSequence) {
return Unsafe.cas(this, SEQUENCE_OFFSET, expectedSequence, expectedSequence + 1);
}
}