org.apache.flink.cep.pattern.conditions.SimpleCondition Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
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*/
package org.apache.flink.cep.pattern.conditions;
import org.apache.flink.annotation.PublicEvolving;
import org.apache.flink.api.common.functions.FilterFunction;
/**
* A user-defined condition that decides if an element should be accepted in the pattern or not.
* Accepting an element also signals a state transition for the corresponding {@link
* org.apache.flink.cep.nfa.NFA}.
*
* Contrary to the {@link IterativeCondition}, conditions that extend this class do not have
* access to the previously accepted elements in the pattern. Conditions that extend this class are
* simple {@code filter(...)} functions that decide based on the properties of the element at hand.
*/
@PublicEvolving
public abstract class SimpleCondition extends IterativeCondition
implements FilterFunction {
private static final long serialVersionUID = 4942618239408140245L;
@Override
public boolean filter(T value, Context ctx) throws Exception {
return filter(value);
}
public static SimpleCondition of(FilterFunction filters) {
return new SimpleCondition() {
@Override
public boolean filter(T value) throws Exception {
return filters.filter(value);
}
};
}
}