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Fast and modular event library for Java

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package net.lenni0451.lambdaevents;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.util.function.Consumer;

/**
 * Mark a method or field as an event handler.

 * The method can have no parameters or one parameter which is the event.

 * The field has to be a {@link Runnable} or a {@link Consumer}.

 * If no event parameter is specified (methods without parameter/consumer fields), {@link EventHandler#events()} has to be specified.
 */
@Target({ElementType.METHOD, ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
public @interface EventHandler {

    /**
     * The priority of the handler.

     * higher = called first

     * lower = called last
     *
     * @return The priority or 0
     */
    int priority() default 0;

    /**
     * The events the handler listens to when no event parameter is present.
     *
     * @return The events or an empty array
     */
    Class[] events() default {};

    /**
     * If the handler should be called even if the event was cancelled by a previous handler.
     *
     * @return If the handler should handle cancelled events
     */
    boolean handleCancelled() default true;

}