/*
* Copyright (c) 2012 LinkedIn Corp.
*
* Licensed 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 com.linkedin.data.transform.filter;
import com.linkedin.data.DataComplex;
import com.linkedin.data.DataList;
import com.linkedin.data.DataMap;
import com.linkedin.data.collections.CheckedUtil;
import java.util.Map;
/**
* Filter that creates filtered data object by copying non-negative masked items from original to new.
* Different algorithm is used according to how sparse the projection is.
*
* @author Keren Jin
*/
public class CopyFilter extends AbstractFilter
{
@Override
protected Object onFilterDataList(DataList data, int start, int count, Object operation)
{
if (operation == FilterConstants.NEGATIVE)
{
return EMPTY_DATALIST;
}
final int end = Math.min(data.size(), start + count);
final int size = Math.max(end - start, 0);
final DataList resultList = new DataList(size);
for (int i = start; i < end; ++i)
{
final Class<?> operationClass = operation.getClass();
final Object original = data.get(i);
final Object value;
if (operationClass == Integer.class)
{
value = original;
}
else
{
assert(operationClass == DataMap.class);
assert(original instanceof DataComplex);
value = filter(original, (DataMap) operation);
}
CheckedUtil.addWithoutChecking(resultList, value);
}
return resultList;
}
@Override
protected Object onFilterDataMap(DataMap data, Map<String, Object> fieldToOperation)
{
final DataMap resultMap = new DataMap((int)(fieldToOperation.size() / 0.75f + 1));
for (Map.Entry<String, Object> entry : fieldToOperation.entrySet())
{
final Object operation = entry.getValue();
final Object value;
if (operation == FilterConstants.POSITIVE)
{
value = data.get(entry.getKey());
}
else
{
assert(operation.getClass() == DataMap.class);
final Object original = data.get(entry.getKey());
assert(original instanceof DataComplex);
value = filter(original, (DataMap) operation);
}
CheckedUtil.putWithoutChecking(resultMap, entry.getKey(), value);
}
return resultMap;
}
@Override
protected Object onError(Object field, String format, Object... args)
{
throw new RuntimeException(String.format(format, args));
}
@Override
protected boolean isValidDataMapFieldOperation(Map<String, Object> result, String name, Object operation)
{
return operation != FilterConstants.NEGATIVE;
}
private static final DataList EMPTY_DATALIST = new DataList();
static
{
EMPTY_DATALIST.makeReadOnly();
}
}