/*******************************************************************************
* Copyright 2014 Analog Devices, Inc.
*
* 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.analog.lyric.dimple.factorfunctions.core;
import org.eclipse.jdt.annotation.Nullable;
/**
* Common implementation base for {@link IFactorTableIterator}s.
*/
abstract class FactorTableIteratorBase implements IFactorTableIterator
{
int _sparseIndex = 0;
double _energy = Double.POSITIVE_INFINITY;
double _weight = 0.0;
@Nullable FactorTableEntry _entry = null;
@Nullable int[] _jointIndices = null;
FactorTableIteratorBase()
{
}
@Override
public final @Nullable FactorTableEntry next()
{
advance();
return getEntry();
}
@Override
public final void remove()
{
throw new UnsupportedOperationException("IFactorTableIterator.remove");
}
@Override
public final @Nullable FactorTableEntry getEntry()
{
if (_entry == null && !done())
{
makeEntry();
}
return _entry;
}
@Override
public final double energy()
{
return _energy;
}
@Override
public final int[] indices()
{
return indices(null);
}
@Override
public final int[] indices(@Nullable int[] array)
{
final int[] unsafeResult = indicesUnsafe();
final int length = unsafeResult.length;
if (array == null || array.length < length)
{
array = new int[length];
}
System.arraycopy(unsafeResult, 0, array, 0, length);
return array;
}
@Override
public final int sparseIndex()
{
return _sparseIndex;
}
@Override
public final double weight()
{
return _weight;
}
abstract boolean done();
abstract void makeEntry();
}