1 /* 2 * Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package java.security; 27 28 import javax.security.auth.Subject; 29 30 /** 31 * This interface represents the abstract notion of a principal, which 32 * can be used to represent any entity, such as an individual, a 33 * corporation, and a login id. 34 * 35 * @see java.security.cert.X509Certificate 36 * 37 * @author Li Gong 38 */ 39 public interface Principal { 40 41 /** 42 * Compares this principal to the specified object. Returns true 43 * if the object passed in matches the principal represented by 44 * the implementation of this interface. 45 * 46 * @param another principal to compare with. 47 * 48 * @return true if the principal passed in is the same as that 49 * encapsulated by this principal, and false otherwise. 50 */ equals(Object another)51 public boolean equals(Object another); 52 53 /** 54 * Returns a string representation of this principal. 55 * 56 * @return a string representation of this principal. 57 */ toString()58 public String toString(); 59 60 /** 61 * Returns a hashcode for this principal. 62 * 63 * @return a hashcode for this principal. 64 */ hashCode()65 public int hashCode(); 66 67 /** 68 * Returns the name of this principal. 69 * 70 * @return the name of this principal. 71 */ getName()72 public String getName(); 73 74 /** 75 * Returns true if the specified subject is implied by this principal. 76 * 77 * <p>The default implementation of this method returns true if 78 * {@code subject} is non-null and contains at least one principal that 79 * is equal to this principal. 80 * 81 * <p>Subclasses may override this with a different implementation, if 82 * necessary. 83 * 84 * @param subject the {@code Subject} 85 * @return true if {@code subject} is non-null and is 86 * implied by this principal, or false otherwise. 87 * @since 1.8 88 */ implies(Subject subject)89 public default boolean implies(Subject subject) { 90 if (subject == null) 91 return false; 92 return subject.getPrincipals().contains(this); 93 } 94 } 95