CavalliumDBEngine/src/main/java/it/cavallium/dbengine/database/collections/DatabaseSingleBucket.java
2022-03-16 13:47:56 +01:00

255 lines
7.1 KiB
Java

package it.cavallium.dbengine.database.collections;
import io.netty5.buffer.api.Drop;
import io.netty5.buffer.api.Owned;
import io.netty5.buffer.api.Send;
import it.cavallium.dbengine.client.BadBlock;
import it.cavallium.dbengine.client.CompositeSnapshot;
import it.cavallium.dbengine.database.Delta;
import it.cavallium.dbengine.database.LLUtils;
import io.netty5.buffer.api.internal.ResourceSupport;
import it.cavallium.dbengine.database.UpdateReturnMode;
import it.cavallium.dbengine.database.serialization.SerializationFunction;
import it.unimi.dsi.fastutil.objects.ObjectArraySet;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Objects;
import java.util.Set;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;
@SuppressWarnings("unused")
public class DatabaseSingleBucket<K, V, TH>
extends ResourceSupport<DatabaseStage<V>, DatabaseSingleBucket<K, V, TH>>
implements DatabaseStageEntry<V> {
private static final Logger logger = LogManager.getLogger(DatabaseSingleBucket.class);
private static final Drop<DatabaseSingleBucket<?, ?, ?>> DROP = new Drop<>() {
@Override
public void drop(DatabaseSingleBucket<?, ?, ?> obj) {
try {
if (obj.bucketStage != null) {
obj.bucketStage.close();
}
} catch (Throwable ex) {
logger.error("Failed to close bucketStage", ex);
}
try {
if (obj.onClose != null) {
obj.onClose.run();
}
} catch (Throwable ex) {
logger.error("Failed to close onClose", ex);
}
}
@Override
public Drop<DatabaseSingleBucket<?, ?, ?>> fork() {
return this;
}
@Override
public void attach(DatabaseSingleBucket<?, ?, ?> obj) {
}
};
private final K key;
private DatabaseStageEntry<ObjectArraySet<Entry<K, V>>> bucketStage;
private Runnable onClose;
@SuppressWarnings({"unchecked", "rawtypes"})
public DatabaseSingleBucket(DatabaseStageEntry<ObjectArraySet<Entry<K, V>>> bucketStage, K key, Runnable onClose) {
super((Drop<DatabaseSingleBucket<K,V,TH>>) (Drop) DROP);
this.key = key;
this.bucketStage = bucketStage;
this.onClose = onClose;
}
@SuppressWarnings({"unchecked", "rawtypes"})
private DatabaseSingleBucket(Send<DatabaseStage<ObjectArraySet<Entry<K, V>>>> bucketStage, K key, Runnable onClose) {
super((Drop<DatabaseSingleBucket<K,V,TH>>) (Drop) DROP);
this.key = key;
this.bucketStage = (DatabaseStageEntry<ObjectArraySet<Entry<K, V>>>) bucketStage.receive();
this.onClose = onClose;
}
@Override
public Mono<V> get(@Nullable CompositeSnapshot snapshot, boolean existsAlmostCertainly) {
return bucketStage.get(snapshot, existsAlmostCertainly).flatMap(this::extractValueTransformation);
}
@Override
public Mono<V> getOrDefault(@Nullable CompositeSnapshot snapshot, Mono<V> defaultValue) {
return bucketStage.get(snapshot).flatMap(this::extractValueTransformation).switchIfEmpty(defaultValue);
}
@Override
public Mono<Void> set(V value) {
return this.update(prev -> value, UpdateReturnMode.NOTHING).then();
}
@Override
public Mono<V> setAndGetPrevious(V value) {
return this.update(prev -> value, UpdateReturnMode.GET_OLD_VALUE);
}
@Override
public Mono<Boolean> setAndGetChanged(V value) {
return this.updateAndGetDelta(prev -> value).map(LLUtils::isDeltaChanged);
}
@Override
public Mono<V> update(SerializationFunction<@Nullable V, @Nullable V> updater, UpdateReturnMode updateReturnMode) {
return bucketStage
.update(oldBucket -> {
V oldValue = extractValue(oldBucket);
V newValue = updater.apply(oldValue);
if (newValue == null) {
return this.removeValueOrDelete(oldBucket);
} else {
return this.insertValueOrCreate(oldBucket, newValue);
}
}, updateReturnMode)
.flatMap(this::extractValueTransformation);
}
@Override
public Mono<Delta<V>> updateAndGetDelta(SerializationFunction<@Nullable V, @Nullable V> updater) {
return bucketStage
.updateAndGetDelta(oldBucket -> {
V oldValue = extractValue(oldBucket);
var result = updater.apply(oldValue);
if (result == null) {
return this.removeValueOrDelete(oldBucket);
} else {
return this.insertValueOrCreate(oldBucket, result);
}
})
.transform(mono -> LLUtils.mapDelta(mono, this::extractValue));
}
@Override
public Mono<Void> clear() {
return this.update(prev -> null, UpdateReturnMode.NOTHING).then();
}
@Override
public Mono<V> clearAndGetPrevious() {
return this.update(prev -> null, UpdateReturnMode.GET_OLD_VALUE);
}
@Override
public Mono<Boolean> clearAndGetStatus() {
return this.updateAndGetDelta(prev -> null).map(LLUtils::isDeltaChanged);
}
@Override
public Mono<Long> leavesCount(@Nullable CompositeSnapshot snapshot, boolean fast) {
return this.get(snapshot).map(prev -> 1L).defaultIfEmpty(0L);
}
@Override
public Mono<Boolean> isEmpty(@Nullable CompositeSnapshot snapshot) {
return this.get(snapshot).map(prev -> true).defaultIfEmpty(true);
}
@Override
public DatabaseStageEntry<V> entry() {
return this;
}
@Override
public Flux<BadBlock> badBlocks() {
return bucketStage.badBlocks();
}
private Mono<V> extractValueTransformation(Set<Entry<K, V>> entries) {
return Mono.fromCallable(() -> extractValue(entries));
}
@Nullable
private V extractValue(Set<Entry<K, V>> entries) {
if (entries == null) return null;
for (Entry<K, V> entry : entries) {
if (Objects.equals(entry.getKey(), key)) {
return entry.getValue();
}
}
return null;
}
@NotNull
private ObjectArraySet<Entry<K, V>> insertValueOrCreate(@Nullable ObjectArraySet<Entry<K, V>> entries, V value) {
if (entries != null) {
var clonedEntries = entries.clone();
var it = clonedEntries.iterator();
while (it.hasNext()) {
var entry = it.next();
if (Objects.equals(entry.getKey(), key)) {
it.remove();
break;
}
}
clonedEntries.add(Map.entry(key, value));
return clonedEntries;
} else {
var oas = new ObjectArraySet<Entry<K, V>>(1);
oas.add(Map.entry(key, value));
return oas;
}
}
@Nullable
private ObjectArraySet<Entry<K, V>> removeValueOrDelete(@Nullable ObjectArraySet<Entry<K, V>> entries) {
if (entries != null) {
var clonedEntries = entries.clone();
var it = clonedEntries.iterator();
while (it.hasNext()) {
var entry = it.next();
if (Objects.equals(entry.getKey(), key)) {
it.remove();
break;
}
}
if (clonedEntries.size() == 0) {
return null;
} else {
return clonedEntries;
}
} else {
return null;
}
}
@Override
protected RuntimeException createResourceClosedException() {
throw new IllegalStateException("Closed");
}
@Override
protected Owned<DatabaseSingleBucket<K, V, TH>> prepareSend() {
var bucketStage = this.bucketStage.send();
var onClose = this.onClose;
return drop -> {
var instance = new DatabaseSingleBucket<K, V, TH>(bucketStage, key, onClose);
drop.attach(instance);
return instance;
};
}
@Override
protected void makeInaccessible() {
this.bucketStage = null;
this.onClose = null;
}
}