io.hops.transaction.context.CachePoolContext.java Source code

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Here is the source code for io.hops.transaction.context.CachePoolContext.java

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/*
 * 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 io.hops.transaction.context;

import io.hops.exception.StorageCallPreventedException;
import io.hops.exception.StorageException;
import io.hops.exception.TransactionContextException;
import io.hops.metadata.common.FinderType;
import io.hops.metadata.hdfs.dal.CachePoolDataAccess;
import io.hops.transaction.lock.TransactionLocks;
import java.util.Collection;
import java.util.HashSet;
import java.util.Set;
import org.apache.hadoop.hdfs.server.namenode.CachePool;

public class CachePoolContext extends BaseEntityContext<String, CachePool> {

    private CachePoolDataAccess<CachePool> dataAccess;
    private Set<CachePool> pools;

    public CachePoolContext(CachePoolDataAccess dataAccess) {
        this.dataAccess = dataAccess;
    }

    @Override
    public CachePool find(FinderType<CachePool> finder, Object... params)
            throws TransactionContextException, StorageException {
        CachePool.Finder hbFinder = (CachePool.Finder) finder;
        switch (hbFinder) {
        case ByName:
            return findByPrimaryKey(hbFinder, params);
        default:
            throw new RuntimeException(UNSUPPORTED_FINDER);
        }
    }

    @Override
    public Collection<CachePool> findList(FinderType<CachePool> finder, Object... params)
            throws TransactionContextException, StorageException {
        CachePool.Finder hbFinder = (CachePool.Finder) finder;
        switch (hbFinder) {
        case All:
            return findAll(hbFinder, params);
        default:
            throw new RuntimeException(UNSUPPORTED_FINDER);
        }
    }

    private CachePool findByPrimaryKey(CachePool.Finder hbFinder, Object[] params)
            throws StorageException, StorageCallPreventedException {
        String pk = (String) params[0];
        CachePool result;
        if (contains(pk)) {
            result = get(pk);
            hit(hbFinder, result, "name", pk);
        } else {
            aboutToAccessStorage(hbFinder, params);
            result = dataAccess.find(pk);
            if (pools == null) {
                pools = new HashSet<>();
            }
            pools.add(result);
            gotFromDB(pk, result);
            miss(hbFinder, result, "name", pk);
        }

        return result;
    }

    private Collection<CachePool> findAll(CachePool.Finder hbFinder, Object[] params)
            throws StorageException, StorageCallPreventedException, TransactionContextException {
        if (pools != null) {
            return pools;
        } else {
            aboutToAccessStorage(hbFinder, params);
            Collection<CachePool> result = dataAccess.findAll();
            if (pools == null) {
                pools = new HashSet<>();
            }
            pools.addAll(result);
            gotFromDB(result);
            miss(hbFinder, result);
            return pools;
        }
    }

    @Override
    public void prepare(TransactionLocks tlm) throws TransactionContextException, StorageException {
        dataAccess.prepare(getRemoved(), getModified());
    }

    @Override
    String getKey(CachePool CachePool) {
        return CachePool.getPoolName();
    }

}