com.palantir.atlasdb.transaction.impl.SweepStrategyManagers.java Source code

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Here is the source code for com.palantir.atlasdb.transaction.impl.SweepStrategyManagers.java

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/**
 * Copyright 2015 Palantir Technologies
 *
 * Licensed under the BSD-3 License (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://opensource.org/licenses/BSD-3-Clause
 *
 * 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 com.palantir.atlasdb.transaction.impl;

import java.util.Map;
import java.util.Set;

import com.google.common.base.Functions;
import com.google.common.base.Supplier;
import com.google.common.base.Suppliers;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Maps;
import com.google.common.collect.Maps.EntryTransformer;
import com.palantir.atlasdb.keyvalue.api.KeyValueService;
import com.palantir.atlasdb.protos.generated.TableMetadataPersistence.SweepStrategy;
import com.palantir.atlasdb.table.description.Schema;
import com.palantir.atlasdb.table.description.TableMetadata;

public class SweepStrategyManagers {
    private SweepStrategyManagers() {
        //
    }

    public static SweepStrategyManager createDefault(KeyValueService kvs) {
        return new SweepStrategyManager(getSweepStrategySupplier(kvs));
    }

    public static SweepStrategyManager createFromSchema(Schema schema) {
        return new SweepStrategyManager(
                RecomputingSupplier.create(Suppliers.ofInstance(getSweepStrategies(schema))));
    }

    public static SweepStrategyManager fromMap(final Map<String, SweepStrategy> map) {
        return new SweepStrategyManager(RecomputingSupplier.create(Suppliers.ofInstance(map)));
    }

    public static SweepStrategyManager completelyConservative(KeyValueService kvs) {
        return new SweepStrategyManager(getConservativeManager(kvs));
    }

    private static RecomputingSupplier<Map<String, SweepStrategy>> getConservativeManager(
            final KeyValueService kvs) {
        return RecomputingSupplier.create(new Supplier<Map<String, SweepStrategy>>() {
            @Override
            public Map<String, SweepStrategy> get() {
                Set<String> tables = kvs.getAllTableNames();
                return Maps.asMap(tables, Functions.constant(SweepStrategy.CONSERVATIVE));
            }
        });
    }

    private static RecomputingSupplier<Map<String, SweepStrategy>> getSweepStrategySupplier(
            final KeyValueService keyValueService) {
        return RecomputingSupplier.create(new Supplier<Map<String, SweepStrategy>>() {
            @Override
            public Map<String, SweepStrategy> get() {
                return getSweepStrategies(keyValueService);
            }
        });
    }

    private static Map<String, SweepStrategy> getSweepStrategies(KeyValueService kvs) {
        return ImmutableMap.copyOf(Maps.transformEntries(kvs.getMetadataForTables(),
                new EntryTransformer<String, byte[], SweepStrategy>() {
                    @Override
                    public SweepStrategy transformEntry(String tableName, byte[] tableMetadata) {
                        if (tableMetadata != null && tableMetadata.length > 0) {
                            return TableMetadata.BYTES_HYDRATOR.hydrateFromBytes(tableMetadata).getSweepStrategy();
                        } else {
                            return SweepStrategy.CONSERVATIVE;
                        }
                    }
                }));
    }

    private static Map<String, SweepStrategy> getSweepStrategies(Schema schema) {
        Map<String, SweepStrategy> ret = Maps.newHashMap();
        for (Map.Entry<String, TableMetadata> e : schema.getAllTablesAndIndexMetadata().entrySet()) {
            ret.put(e.getKey(), e.getValue().getSweepStrategy());
        }
        return ret;
    }
}