/*
* 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 org.apache.flink.streaming.api.functions.aggregation;
import java.io.Serializable;
import org.apache.flink.annotation.Internal;
/**
* Internal function for summing up contents of fields. This is used with {@link SumAggregator}.
*/
@Internal
public abstract class SumFunction implements Serializable {
private static final long serialVersionUID = 1L;
public abstract Object add(Object o1, Object o2);
public static SumFunction getForClass(Class<?> clazz) {
if (clazz == Integer.class) {
return new IntSum();
} else if (clazz == Long.class) {
return new LongSum();
} else if (clazz == Short.class) {
return new ShortSum();
} else if (clazz == Double.class) {
return new DoubleSum();
} else if (clazz == Float.class) {
return new FloatSum();
} else if (clazz == Byte.class) {
return new ByteSum();
} else {
throw new RuntimeException("DataStream cannot be summed because the class "
+ clazz.getSimpleName() + " does not support the + operator.");
}
}
static class IntSum extends SumFunction {
private static final long serialVersionUID = 1L;
@Override
public Object add(Object value1, Object value2) {
return (Integer) value1 + (Integer) value2;
}
}
static class LongSum extends SumFunction {
private static final long serialVersionUID = 1L;
@Override
public Object add(Object value1, Object value2) {
return (Long) value1 + (Long) value2;
}
}
static class DoubleSum extends SumFunction {
private static final long serialVersionUID = 1L;
@Override
public Object add(Object value1, Object value2) {
return (Double) value1 + (Double) value2;
}
}
static class ShortSum extends SumFunction {
private static final long serialVersionUID = 1L;
@Override
public Object add(Object value1, Object value2) {
return (short) ((Short) value1 + (Short) value2);
}
}
static class FloatSum extends SumFunction {
private static final long serialVersionUID = 1L;
@Override
public Object add(Object value1, Object value2) {
return (Float) value1 + (Float) value2;
}
}
static class ByteSum extends SumFunction {
private static final long serialVersionUID = 1L;
@Override
public Object add(Object value1, Object value2) {
return (byte) ((Byte) value1 + (Byte) value2);
}
}
}