EnablingPredicate.java

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package org.orekit.propagation.events;

import org.orekit.propagation.SpacecraftState;

import java.util.Arrays;

/** This interface represents an event enabling predicate function.
 * @author Luc Maisonobe
 * @since 7.1
 */
public interface EnablingPredicate {

    /** Compute an event enabling function of state.
     * @param state current state
     * @param detector underlying detector
     * @param g value of the underlying detector for the current state
     * @return true if the event is enabled (i.e. it can be
     * triggered), false if it should be ignored
     */
    boolean eventIsEnabled(SpacecraftState state, EventDetector detector, double g);

    /**
     * Method combining predicated based on the OR logic operator.
     * @param enablingPredicates predicates
     * @return combined predicate
     * @since 13.1
     */
    static EnablingPredicate orCombine(EnablingPredicate... enablingPredicates) {
        return (state, detector, g) -> Arrays.stream(enablingPredicates).anyMatch(p -> p.eventIsEnabled(state, detector, g));
    }

    /**
     * Method combining predicated based on the AND logic operator.
     * @param enablingPredicates predicates
     * @return combined predicate
     * @since 13.1
     */
    static EnablingPredicate andCombine(EnablingPredicate... enablingPredicates) {
        return (state, detector, g) -> Arrays.stream(enablingPredicates).allMatch(p -> p.eventIsEnabled(state, detector, g));
    }
}