All Downloads are FREE. Search and download functionalities are using the official Maven repository.
  • Log In
  • Register

    • info.archinnov.achilles.iterator.ThriftJoinSliceIterator Maven / Gradle / Ivy

    package info.archinnov.achilles.iterator;

import static info.archinnov.achilles.dao.ThriftAbstractDao.DEFAULT_LENGTH;
import static info.archinnov.achilles.iterator.ThriftAbstractSliceIterator.IteratorType.THRIFT_JOIN_SLICE_ITERATOR;
import info.archinnov.achilles.consistency.AchillesConsistencyLevelPolicy;
import info.archinnov.achilles.context.execution.SafeExecutionContext;
import info.archinnov.achilles.dao.ThriftGenericEntityDao;
import info.archinnov.achilles.entity.metadata.PropertyMeta;
import info.archinnov.achilles.helper.ThriftJoinEntityHelper;
import info.archinnov.achilles.type.Pair;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import me.prettyprint.hector.api.beans.Composite;
import me.prettyprint.hector.api.beans.HColumn;
import me.prettyprint.hector.api.query.SliceQuery;

/**
 * ThriftJoinSliceIterator
 * 
 * @author DuyHai DOAN
 * 
 *         Modification of original version from Hector ColumnSliceIterator
 * 
 */
public class ThriftJoinSliceIterator extends
		ThriftAbstractSliceIterator>
{

	private SliceQuery query;
	private PropertyMeta propertyMeta;
	private ThriftJoinEntityHelper joinHelper = new ThriftJoinEntityHelper();
	private ThriftGenericEntityDao joinEntityDao;

	public ThriftJoinSliceIterator( //
			AchillesConsistencyLevelPolicy policy, //
			ThriftGenericEntityDao joinEntityDao, //
			String cf, PropertyMeta propertyMeta, //
			SliceQuery query, Composite start, //
			final Composite finish, boolean reversed)
	{
		this(policy, joinEntityDao, cf, propertyMeta, query, start, finish, reversed,
				DEFAULT_LENGTH);
	}

	public ThriftJoinSliceIterator(AchillesConsistencyLevelPolicy policy, //
			ThriftGenericEntityDao joinEntityDao, //
			String cf, PropertyMeta propertyMeta, //
			SliceQuery query, Composite start, //
			final Composite finish, boolean reversed, int count)
	{
		this(policy, joinEntityDao, cf, propertyMeta, query, start, new ColumnSliceFinish()
		{
			@Override
			public Composite function()
			{
				return finish;
			}
		}, reversed, count);
	}

	public ThriftJoinSliceIterator(AchillesConsistencyLevelPolicy policy, //
			ThriftGenericEntityDao joinEntityDao, //
			String cf, PropertyMeta propertyMeta, //
			SliceQuery query, Composite start, //
			ColumnSliceFinish finish, boolean reversed)
	{
		this(policy, joinEntityDao, cf, propertyMeta, query, start, finish, reversed,
				DEFAULT_LENGTH);
	}

	public ThriftJoinSliceIterator(AchillesConsistencyLevelPolicy policy, //
			ThriftGenericEntityDao joinEntityDao, //
			String cf, PropertyMeta propertyMeta, //
			SliceQuery query, Composite start, //
			ColumnSliceFinish finish, boolean reversed, int count)
	{
		super(policy, cf, start, finish, reversed, count);
		this.joinEntityDao = joinEntityDao;
		this.propertyMeta = propertyMeta;
		this.query = query;
		this.query.setRange(this.start, this.finish.function(), this.reversed, this.count);
	}

	@Override
	protected Iterator> fetchData()
	{

		Iterator> iter = executeWithInitialConsistencyLevel(new SafeExecutionContext>>()
		{
			@Override
			public Iterator> execute()
			{
				return query.execute().get().getColumns().iterator();
			}
		});

		List joinIds = new ArrayList();
		Map> hColumMap = new HashMap>();

		while (iter.hasNext())
		{
			HColumn hColumn = iter.next();

			PropertyMeta joinIdMeta = propertyMeta.joinIdMeta();

			Object joinId;
			if (propertyMeta.type().isWideMap())
			{
				joinId = joinIdMeta.castValue(hColumn.getValue());
			}
			else
			{
				joinId = joinIdMeta.getValueFromString(hColumn.getValue());

			}
			joinIds.add(joinId);
			hColumMap
					.put(joinId, new Pair(hColumn.getName(), hColumn.getTtl()));
		}
		List> joinedHColumns = new ArrayList>();

		if (joinIds.size() > 0)
		{

			Map loadedEntities = joinHelper.loadJoinEntities(
					propertyMeta.getValueClass(), joinIds, propertyMeta.joinMeta(), joinEntityDao);

			for (Object joinId : joinIds)
			{
				Pair pair = hColumMap.get(joinId);
				Composite name = pair.left;
				Integer ttl = pair.right;

				HColumn joinedHColumn = new ThriftJoinHColumn();

				joinedHColumn.setName(name).setValue(loadedEntities.get(joinId)).setTtl(ttl);
				joinedHColumns.add(joinedHColumn);
			}
		}
		return joinedHColumns.iterator();
	}

	@Override
	public HColumn next()
	{
		HColumn column = iterator.next();
		start = column.getName();
		columns++;

		return column;
	}

	@Override
	public void remove()
	{
		iterator.remove();
	}

	@Override
	protected void changeQueryRange()
	{
		query.setRange(start, finish.function(), reversed, count);
	}

	@Override
	protected void resetStartColumn(HColumn column)
	{
		start = column.getName();
	}

	@Override
	public IteratorType type()
	{
		return THRIFT_JOIN_SLICE_ITERATOR;
	}
}
    
    
    
    

    




    
    
    © 2015 - 2025 Weber Informatics LLC | Privacy Policy