streaming/src/main/java/org/apache/gearpump/streaming/refactor/coder/ElementByteSizeObserver.java

/*
 * 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.gearpump.streaming.refactor.coder;

import java.util.Observable;
import java.util.Observer;

public abstract class ElementByteSizeObserver implements Observer {
    private boolean isLazy = false;
    private long totalSize = 0;
    private double scalingFactor = 1.0;

    public ElementByteSizeObserver() {
    }

    protected abstract void reportElementSize(long elementByteSize);

    public void setLazy() {
        isLazy = true;
    }

    public boolean getIsLazy() {
        return isLazy;
    }

    public void update(Object obj) {
        update(null, obj);
    }

    public void setScalingFactor(double scalingFactor) {
        this.scalingFactor = scalingFactor;
    }

    @Override
    public void update(Observable obs, Object obj) {
        if (obj instanceof Long) {
            totalSize += scalingFactor * (Long) obj;
        } else if (obj instanceof Integer) {
            totalSize += scalingFactor * (Integer) obj;
        } else {
            throw new AssertionError("unexpected parameter object");
        }
    }

    public void advance() {
        reportElementSize(totalSize);
        totalSize = 0;
        isLazy = false;
    }
}