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19
20
21 package org.apache.james.jspf.terms;
22
23 import org.apache.james.jspf.core.SPFChecker;
24
25 /**
26 * This Interface represent a modifier
27 *
28 */
29 public interface Modifier extends SPFChecker {
30
31 /**
32 * Return true if the Modifier is only allowed once
33 *
34 * @return true if only one instance of this modifier is allowed
35 */
36 public boolean enforceSingleInstance();
37 }