org.apache.flink.runtime.state.heap.HeapMapState Maven / Gradle / Ivy

Go to download
/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.flink.runtime.state.heap;

import org.apache.flink.api.common.state.MapState;
import org.apache.flink.api.common.state.State;
import org.apache.flink.api.common.state.StateDescriptor;
import org.apache.flink.api.common.typeutils.TypeSerializer;
import org.apache.flink.api.common.typeutils.base.MapSerializer;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.queryablestate.client.state.serialization.KvStateSerializer;
import org.apache.flink.runtime.state.internal.InternalMapState;
import org.apache.flink.util.Preconditions;

import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

/**
 * Heap-backed partitioned {@link MapState} that is snapshotted into files.
 *
 * @param  The type of the key.
 * @param  The type of the namespace.
 * @param  The type of the keys in the state.
 * @param  The type of the values in the state.
 */
class HeapMapState extends AbstractHeapState>
        implements InternalMapState {

    /**
     * Creates a new key/value state for the given hash map of key/value pairs.
     *
     * @param stateTable The state table for which this state is associated to.
     * @param keySerializer The serializer for the keys.
     * @param valueSerializer The serializer for the state.
     * @param namespaceSerializer The serializer for the namespace.
     * @param defaultValue The default value for the state.
     */
    private HeapMapState(
            StateTable> stateTable,
            TypeSerializer keySerializer,
            TypeSerializer> valueSerializer,
            TypeSerializer namespaceSerializer,
            Map defaultValue) {
        super(stateTable, keySerializer, valueSerializer, namespaceSerializer, defaultValue);

        Preconditions.checkState(
                valueSerializer instanceof MapSerializer, "Unexpected serializer type.");
    }

    @Override
    public TypeSerializer getKeySerializer() {
        return keySerializer;
    }

    @Override
    public TypeSerializer getNamespaceSerializer() {
        return namespaceSerializer;
    }

    @Override
    public TypeSerializer> getValueSerializer() {
        return valueSerializer;
    }

    @Override
    public UV get(UK userKey) {

        Map userMap = stateTable.get(currentNamespace);

        if (userMap == null) {
            return null;
        }

        return userMap.get(userKey);
    }

    @Override
    public void put(UK userKey, UV userValue) {

        Map userMap = stateTable.get(currentNamespace);
        if (userMap == null) {
            userMap = new HashMap<>();
            stateTable.put(currentNamespace, userMap);
        }

        userMap.put(userKey, userValue);
    }

    @Override
    public void putAll(Map value) {

        Map userMap = stateTable.get(currentNamespace);

        if (userMap == null) {
            userMap = new HashMap<>();
            stateTable.put(currentNamespace, userMap);
        }

        userMap.putAll(value);
    }

    @Override
    public void remove(UK userKey) {

        Map userMap = stateTable.get(currentNamespace);
        if (userMap == null) {
            return;
        }

        userMap.remove(userKey);

        if (userMap.isEmpty()) {
            clear();
        }
    }

    @Override
    public boolean contains(UK userKey) {
        Map userMap = stateTable.get(currentNamespace);
        return userMap != null && userMap.containsKey(userKey);
    }

    @Override
    public Iterable> entries() {
        Map userMap = stateTable.get(currentNamespace);
        return userMap == null ? Collections.emptySet() : userMap.entrySet();
    }

    @Override
    public Iterable keys() {
        Map userMap = stateTable.get(currentNamespace);
        return userMap == null ? Collections.emptySet() : userMap.keySet();
    }

    @Override
    public Iterable values() {
        Map userMap = stateTable.get(currentNamespace);
        return userMap == null ? Collections.emptySet() : userMap.values();
    }

    @Override
    public Iterator> iterator() {
        Map userMap = stateTable.get(currentNamespace);
        return userMap == null ? Collections.emptyIterator() : userMap.entrySet().iterator();
    }

    @Override
    public boolean isEmpty() {
        Map userMap = stateTable.get(currentNamespace);
        return userMap == null || userMap.isEmpty();
    }

    @Override
    public byte[] getSerializedValue(
            final byte[] serializedKeyAndNamespace,
            final TypeSerializer safeKeySerializer,
            final TypeSerializer safeNamespaceSerializer,
            final TypeSerializer> safeValueSerializer)
            throws Exception {

        Preconditions.checkNotNull(serializedKeyAndNamespace);
        Preconditions.checkNotNull(safeKeySerializer);
        Preconditions.checkNotNull(safeNamespaceSerializer);
        Preconditions.checkNotNull(safeValueSerializer);

        Tuple2 keyAndNamespace =
                KvStateSerializer.deserializeKeyAndNamespace(
                        serializedKeyAndNamespace, safeKeySerializer, safeNamespaceSerializer);

        Map result = stateTable.get(keyAndNamespace.f0, keyAndNamespace.f1);

        if (result == null) {
            return null;
        }

        final MapSerializer serializer = (MapSerializer) safeValueSerializer;

        final TypeSerializer dupUserKeySerializer = serializer.getKeySerializer();
        final TypeSerializer dupUserValueSerializer = serializer.getValueSerializer();

        return KvStateSerializer.serializeMap(
                result.entrySet(), dupUserKeySerializer, dupUserValueSerializer);
    }

    @SuppressWarnings("unchecked")
    static  IS create(
            StateDescriptor stateDesc,
            StateTable stateTable,
            TypeSerializer keySerializer) {
        return (IS)
                new HeapMapState<>(
                        (StateTable>) stateTable,
                        keySerializer,
                        (TypeSerializer>) stateTable.getStateSerializer(),
                        stateTable.getNamespaceSerializer(),
                        (Map) stateDesc.getDefaultValue());
    }
}