Application: gvSIG desktop

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package org.gvsig.fmap.dal.swing.impl.searchPostProcess.distinctOn;

/**

 *

 * @author jovivas

 */

public class FirstAggregateOperation implements AggregateOperation {

    public static class FirstAggregateOperationFactory implements AggregateOperationFactory{

        @Override

        public String getName() {

            return "First value";

        }

        @Override

        public AggregateOperation create(Object... os) {

            return new FirstAggregateOperation();

        }

        @Override

        public boolean isApplicable(Object... value) {

            return true;

        }

    }

    Object first;

    boolean isFirst = true;

    public FirstAggregateOperation() {

        this.first = null;

    }

    @Override

    public boolean isApplicable(Object... value) {

        return true;

    }

    @Override

    public void reset() {

        this.first = null;

        this.isFirst=true;

    }

    @Override

    public void perform(Object value) {    

        if (isFirst) {

            this.first = value;

            isFirst = false;

        }

    }

    @Override

    public Object getValue() {

        return this.first;

    }

}