source: voting/src/main/java/geniusweb/voting/VotingEvaluator.java@ 26

package geniusweb.voting;

import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;
import com.fasterxml.jackson.annotation.JsonSubTypes;
import com.fasterxml.jackson.annotation.JsonTypeInfo;
import com.fasterxml.jackson.annotation.JsonTypeInfo.As;

import geniusweb.inform.Agreements;
import geniusweb.voting.votingevaluators.LargestAgreement;
import geniusweb.voting.votingevaluators.LargestAgreementsLoop;

/**
 * Evaluates the {@link CollectedVotes}, determining the agreements and if the
 * negotiation should continue.
 * 
 * Implementations should be immutable and not serialize internal variables (eg
 * @JsonIgnore them).
 */
@JsonAutoDetect(fieldVisibility = Visibility.ANY, getterVisibility = Visibility.NONE, setterVisibility = Visibility.NONE, isGetterVisibility = Visibility.NONE)
@JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = As.WRAPPER_OBJECT)
@JsonSubTypes({ @JsonSubTypes.Type(value = LargestAgreementsLoop.class),
                @JsonSubTypes.Type(value = LargestAgreement.class) })
public interface VotingEvaluator {
        /**
         * This function is the effective constructor. This mechanism serves several
         * purposes:
         * <ul>
         * <li>It defines the constructor at interface level, so that we can ensure
         * it's available and can call it given an instance,
         * <li>We can use a (typically blank) instance of this to make more
         * instances
         * <li>You can cache intermediate results in the object for caching
         * </ul>
         * 
         * @param votes the Votes made by parties. All active parties in the
         *              negotiation must be available, even if they did not vote, to
         *              ensure that {@link #isFinished()} can work properly.
         * 
         * @return new VotingEvaluation object containing the given votes.
         */
        VotingEvaluator create(CollectedVotes votes);

        /**
         * 
         * @return the agreements that is contained in the current available votes.
         *         The exact procedure varies with the implementation.
         */
        Agreements getAgreements();

        /**
         * 
         * @return true iff the negotiation is finished after taking the agreement
         *         returned by {@link #getAgreements()}
         */
        boolean isFinished();
}