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Converters and Comprehenders for Guava

There is a newer version: 9.0.0-MI7

package com.aol.cyclops.guava.comprehenders;

import java.util.function.Function;

import com.aol.cyclops.types.extensability.Comprehender;
import com.aol.cyclops.types.extensability.ValueComprehender;
import com.google.common.base.Optional;

public class OptionalComprehender implements ValueComprehender{

	@Override
	public Object resolveForCrossTypeFlatMap(Comprehender comp, Optional apply) {
		if(apply.isPresent())
			return comp.of(apply.get());
		return comp.empty();
	}

	@Override
	public Object map(Optional t, Function fn) {
		return t.transform(r->fn.apply(r));
	}

	@Override
	public Object flatMap(Optional t, Function fn) {
		java.util.Optional o = java.util.Optional.empty();
		if(t.isPresent())
			o = java.util.Optional.of(t.get());
		
		java.util.Optional res = o.flatMap(r-> unwrap((Optional)fn.apply(r)));
		Optional ret = Optional.absent();
		if(res.isPresent())
			ret = Optional.of(res.get());
		return ret;
		
	}
	private java.util.Optional unwrap(Optional res){
		
		java.util.Optional ret = java.util.Optional.empty();
		if(res.isPresent())
			ret = java.util.Optional.of(res.get());
		return ret;
	}

	@Override
	public Optional of(Object o) {
		return Optional.of(o);
	}

	@Override
	public Optional empty() {
		return Optional.absent();
	}

	@Override
	public Class getTargetClass() {
		return Optional.class;
	}

}