io.druid.java.util.common.guava.YieldingAccumulator Maven / Gradle / Ivy
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*
* http://www.apache.org/licenses/LICENSE-2.0
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package io.druid.java.util.common.guava;
/**
* A YieldingAccumulator is used along with a Yielder in order to replicate continuations in Java. I'm still not sure
* this is such a great idea, but it's there. We shall see.
*
* The accumulated has its accumulate() method called and has the option of "yielding" its response by calling
* yield() before returning as response. If it chooses not to yield its response, then it expects to get called
* again with the next value and the value it just returned.
*/
public abstract class YieldingAccumulator
{
private boolean yielded = false;
public void yield()
{
yielded = true;
}
public boolean yielded()
{
return yielded;
}
public void reset()
{
yielded = false;
}
public abstract AccumulatedType accumulate(AccumulatedType accumulated, InType in);
}