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005 * regarding copyright ownership. The ASF licenses this file *
006 * to you under the Apache License, Version 2.0 (the *
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019
020
021 package org.apache.james.jspf.terms;
022
023 import org.apache.james.jspf.core.SPFChecker;
024
025 /**
026 * This Interface represent a modifier
027 *
028 */
029 public interface Modifier extends SPFChecker {
030
031 /**
032 * Return true if the Modifier is only allowed once
033 *
034 * @return true if only one instance of this modifier is allowed
035 */
036 public boolean enforceSingleInstance();
037 }