https://openjdk.java.net/ 
/*
 * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */


package java.security;


This class defines the Service Provider Interface (SPI) for the Policy class. All the abstract methods in this class must be implemented by each service provider who wishes to supply a Policy implementation. 
 Subclass implementations of this abstract class must provide a public constructor that takes a Policy.Parameters object as an input parameter. This constructor also must throw an IllegalArgumentException if it does not understand the Policy.Parameters input. 
Since:1.6
/**
 * This class defines the <i>Service Provider Interface</i> (<b>SPI</b>)
 * for the {@code Policy} class.
 * All the abstract methods in this class must be implemented by each
 * service provider who wishes to supply a Policy implementation.
 *
 * <p> Subclass implementations of this abstract class must provide
 * a public constructor that takes a {@code Policy.Parameters}
 * object as an input parameter.  This constructor also must throw
 * an IllegalArgumentException if it does not understand the
 * {@code Policy.Parameters} input.
 *
 *
 * @since 1.6
 */

public abstract class PolicySpi {

    
Check whether the policy has granted a Permission to a ProtectionDomain.

Params:
  • domain – the ProtectionDomain to check.
  • permission – check whether this permission is granted to the
         specified domain.
Returns:boolean true if the permission is granted to the domain.
/**
     * Check whether the policy has granted a Permission to a ProtectionDomain.
     *
     * @param domain the ProtectionDomain to check.
     *
     * @param permission check whether this permission is granted to the
     *          specified domain.
     *
     * @return boolean true if the permission is granted to the domain.
     */
    protected abstract boolean engineImplies
        (ProtectionDomain domain, Permission permission);

    
Refreshes/reloads the policy configuration. The behavior of this method depends on the implementation. For example, calling refresh on a file-based policy will cause the file to be re-read. 
 The default implementation of this method does nothing.
This method should be overridden if a refresh operation is supported
by the policy implementation.

/**
     * Refreshes/reloads the policy configuration. The behavior of this method
     * depends on the implementation. For example, calling {@code refresh}
     * on a file-based policy will cause the file to be re-read.
     *
     * <p> The default implementation of this method does nothing.
     * This method should be overridden if a refresh operation is supported
     * by the policy implementation.
     */
    protected void engineRefresh() { }

    
Return a PermissionCollection object containing the set of
permissions granted to the specified CodeSource.

 The default implementation of this method returns
Policy.UNSUPPORTED_EMPTY_COLLECTION object.  This method can be
overridden if the policy implementation can return a set of
permissions granted to a CodeSource.

Params:
  • codesource – the CodeSource to which the returned
         PermissionCollection has been granted.
Returns:a set of permissions granted to the specified CodeSource.
         If this operation is supported, the returned
         set of permissions must be a new mutable instance
         and it must support heterogeneous Permission types.
         If this operation is not supported,
         Policy.UNSUPPORTED_EMPTY_COLLECTION is returned.
/**
     * Return a PermissionCollection object containing the set of
     * permissions granted to the specified CodeSource.
     *
     * <p> The default implementation of this method returns
     * Policy.UNSUPPORTED_EMPTY_COLLECTION object.  This method can be
     * overridden if the policy implementation can return a set of
     * permissions granted to a CodeSource.
     *
     * @param codesource the CodeSource to which the returned
     *          PermissionCollection has been granted.
     *
     * @return a set of permissions granted to the specified CodeSource.
     *          If this operation is supported, the returned
     *          set of permissions must be a new mutable instance
     *          and it must support heterogeneous Permission types.
     *          If this operation is not supported,
     *          Policy.UNSUPPORTED_EMPTY_COLLECTION is returned.
     */
    protected PermissionCollection engineGetPermissions
                                        (CodeSource codesource) {
        return Policy.UNSUPPORTED_EMPTY_COLLECTION;
    }

    
Return a PermissionCollection object containing the set of
permissions granted to the specified ProtectionDomain.

 The default implementation of this method returns
Policy.UNSUPPORTED_EMPTY_COLLECTION object.  This method can be
overridden if the policy implementation can return a set of
permissions granted to a ProtectionDomain.

Params:
  • domain – the ProtectionDomain to which the returned
         PermissionCollection has been granted.
Returns:a set of permissions granted to the specified ProtectionDomain.
         If this operation is supported, the returned
         set of permissions must be a new mutable instance
         and it must support heterogeneous Permission types.
         If this operation is not supported,
         Policy.UNSUPPORTED_EMPTY_COLLECTION is returned.
/**
     * Return a PermissionCollection object containing the set of
     * permissions granted to the specified ProtectionDomain.
     *
     * <p> The default implementation of this method returns
     * Policy.UNSUPPORTED_EMPTY_COLLECTION object.  This method can be
     * overridden if the policy implementation can return a set of
     * permissions granted to a ProtectionDomain.
     *
     * @param domain the ProtectionDomain to which the returned
     *          PermissionCollection has been granted.
     *
     * @return a set of permissions granted to the specified ProtectionDomain.
     *          If this operation is supported, the returned
     *          set of permissions must be a new mutable instance
     *          and it must support heterogeneous Permission types.
     *          If this operation is not supported,
     *          Policy.UNSUPPORTED_EMPTY_COLLECTION is returned.
     */
    protected PermissionCollection engineGetPermissions
                                        (ProtectionDomain domain) {
        return Policy.UNSUPPORTED_EMPTY_COLLECTION;
    }
}