/* | 
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 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. | 
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | 
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 * | 
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 * This code is free software; you can redistribute it and/or modify it | 
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 * under the terms of the GNU General Public License version 2 only, as | 
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 * published by the Free Software Foundation.  Oracle designates this | 
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 * particular file as subject to the "Classpath" exception as provided | 
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 * by Oracle in the LICENSE file that accompanied this code. | 
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 * | 
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 * This code is distributed in the hope that it will be useful, but WITHOUT | 
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | 
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License | 
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 * version 2 for more details (a copy is included in the LICENSE file that | 
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 * accompanied this code). | 
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 * | 
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 * You should have received a copy of the GNU General Public License version | 
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 * 2 along with this work; if not, write to the Free Software Foundation, | 
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 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | 
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 * | 
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 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | 
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 * or visit www.oracle.com if you need additional information or have any | 
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 * questions. | 
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*/  | 
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package java.security;  | 
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import java.util.Enumeration;  | 
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import java.util.WeakHashMap;  | 
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import java.util.concurrent.atomic.AtomicReference;  | 
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import sun.security.jca.GetInstance;  | 
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import sun.security.util.Debug;  | 
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import sun.security.util.SecurityConstants;  | 
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/**  | 
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* A Policy object is responsible for determining whether code executing  | 
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* in the Java runtime environment has permission to perform a  | 
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* security-sensitive operation.  | 
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*  | 
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* <p> There is only one Policy object installed in the runtime at any  | 
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* given time. A Policy object can be installed by calling the  | 
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 * {@code setPolicy} method.  The installed Policy object can be | 
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 * obtained by calling the {@code getPolicy} method. | 
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*  | 
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* <p> If no Policy object has been installed in the runtime, a call to  | 
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 * {@code getPolicy} installs an instance of the default Policy | 
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* implementation (a default subclass implementation of this abstract class).  | 
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* The default Policy implementation can be changed by setting the value  | 
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 * of the {@code policy.provider} security property to the fully qualified | 
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* name of the desired Policy subclass implementation.  | 
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*  | 
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* <p> Application code can directly subclass Policy to provide a custom  | 
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* implementation. In addition, an instance of a Policy object can be  | 
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 * constructed by invoking one of the {@code getInstance} factory methods | 
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* with a standard type. The default policy type is "JavaPolicy".  | 
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*  | 
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* <p> Once a Policy instance has been installed (either by default, or by  | 
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 * calling {@code setPolicy}), the Java runtime invokes its | 
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 * {@code implies} method when it needs to | 
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* determine whether executing code (encapsulated in a ProtectionDomain)  | 
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* can perform SecurityManager-protected operations. How a Policy object  | 
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* retrieves its policy data is up to the Policy implementation itself.  | 
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* The policy data may be stored, for example, in a flat ASCII file,  | 
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* in a serialized binary file of the Policy class, or in a database.  | 
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*  | 
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 * <p> The {@code refresh} method causes the policy object to | 
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* refresh/reload its data. This operation is implementation-dependent.  | 
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* For example, if the policy object stores its data in configuration files,  | 
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 * calling {@code refresh} will cause it to re-read the configuration | 
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* policy files. If a refresh operation is not supported, this method does  | 
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* nothing. Note that refreshed policy may not have an effect on classes  | 
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* in a particular ProtectionDomain. This is dependent on the Policy  | 
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 * provider's implementation of the {@code implies} | 
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* method and its PermissionCollection caching strategy.  | 
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*  | 
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* @author Roland Schemers  | 
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* @author Gary Ellison  | 
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* @see java.security.Provider  | 
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* @see java.security.ProtectionDomain  | 
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* @see java.security.Permission  | 
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* @see java.security.Security security properties  | 
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*/  | 
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public abstract class Policy { | 
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    /** | 
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     * A read-only empty PermissionCollection instance. | 
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     * @since 1.6 | 
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*/  | 
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public static final PermissionCollection UNSUPPORTED_EMPTY_COLLECTION =  | 
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new UnsupportedEmptyCollection();  | 
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    // Information about the system-wide policy. | 
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    private static class PolicyInfo { | 
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        // the system-wide policy | 
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final Policy policy;  | 
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        // a flag indicating if the system-wide policy has been initialized | 
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final boolean initialized;  | 
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PolicyInfo(Policy policy, boolean initialized) {  | 
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this.policy = policy;  | 
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this.initialized = initialized;  | 
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}  | 
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}  | 
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    // PolicyInfo is stored in an AtomicReference | 
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private static AtomicReference<PolicyInfo> policy =  | 
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new AtomicReference<>(new PolicyInfo(null, false));  | 
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private static final Debug debug = Debug.getInstance("policy");  | 
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    // Cache mapping ProtectionDomain.Key to PermissionCollection | 
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private WeakHashMap<ProtectionDomain.Key, PermissionCollection> pdMapping;  | 
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    /** package private for AccessControlContext and ProtectionDomain */ | 
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static boolean isSet()  | 
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    { | 
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PolicyInfo pi = policy.get();  | 
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return pi.policy != null && pi.initialized == true;  | 
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}  | 
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private static void checkPermission(String type) {  | 
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SecurityManager sm = System.getSecurityManager();  | 
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if (sm != null) {  | 
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sm.checkPermission(new SecurityPermission("createPolicy." + type));  | 
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}  | 
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}  | 
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    /** | 
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     * Returns the installed Policy object. This value should not be cached, | 
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     * as it may be changed by a call to {@code setPolicy}. | 
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     * This method first calls | 
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     * {@code SecurityManager.checkPermission} with a | 
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     * {@code SecurityPermission("getPolicy")} permission | 
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     * to ensure it's ok to get the Policy object. | 
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     * | 
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     * @return the installed Policy. | 
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     * | 
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     * @throws SecurityException | 
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     *        if a security manager exists and its | 
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     *        {@code checkPermission} method doesn't allow | 
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     *        getting the Policy object. | 
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     * | 
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     * @see SecurityManager#checkPermission(Permission) | 
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     * @see #setPolicy(java.security.Policy) | 
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*/  | 
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public static Policy getPolicy()  | 
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    { | 
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SecurityManager sm = System.getSecurityManager();  | 
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if (sm != null)  | 
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sm.checkPermission(SecurityConstants.GET_POLICY_PERMISSION);  | 
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return getPolicyNoCheck();  | 
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}  | 
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    /** | 
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     * Returns the installed Policy object, skipping the security check. | 
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     * Used by ProtectionDomain and getPolicy. | 
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     * | 
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     * @return the installed Policy. | 
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*/  | 
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static Policy getPolicyNoCheck()  | 
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    { | 
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PolicyInfo pi = policy.get();  | 
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// Use double-check idiom to avoid locking if system-wide policy is  | 
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        // already initialized | 
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if (pi.initialized == false || pi.policy == null) {  | 
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synchronized (Policy.class) {  | 
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PolicyInfo pinfo = policy.get();  | 
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if (pinfo.policy == null) {  | 
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String policy_class = AccessController.doPrivileged(  | 
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new PrivilegedAction<String>() {  | 
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public String run() {  | 
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return Security.getProperty("policy.provider");  | 
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}  | 
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});  | 
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if (policy_class == null) {  | 
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policy_class = "sun.security.provider.PolicyFile";  | 
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}  | 
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                    try { | 
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pinfo = new PolicyInfo(  | 
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(Policy) Class.forName(policy_class).newInstance(),  | 
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true);  | 
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} catch (Exception e) {  | 
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/*  | 
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* The policy_class seems to be an extension  | 
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* so we have to bootstrap loading it via a policy  | 
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* provider that is on the bootclasspath.  | 
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* If it loads then shift gears to using the configured  | 
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* provider.  | 
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*/  | 
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                        // install the bootstrap provider to avoid recursion | 
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Policy polFile = new sun.security.provider.PolicyFile();  | 
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pinfo = new PolicyInfo(polFile, false);  | 
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policy.set(pinfo);  | 
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final String pc = policy_class;  | 
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Policy pol = AccessController.doPrivileged(  | 
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new PrivilegedAction<Policy>() {  | 
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public Policy run() {  | 
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                                try { | 
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ClassLoader cl =  | 
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ClassLoader.getSystemClassLoader();  | 
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                                    // we want the extension loader | 
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ClassLoader extcl = null;  | 
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while (cl != null) {  | 
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extcl = cl;  | 
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cl = cl.getParent();  | 
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}  | 
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return (extcl != null ? (Policy)Class.forName(  | 
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pc, true, extcl).newInstance() : null);  | 
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} catch (Exception e) {  | 
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if (debug != null) {  | 
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debug.println("policy provider " +  | 
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pc +  | 
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                                                    " not available"); | 
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e.printStackTrace();  | 
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}  | 
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return null;  | 
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}  | 
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}  | 
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});  | 
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                        /* | 
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                         * if it loaded install it as the policy provider. Otherwise | 
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                         * continue to use the system default implementation | 
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*/  | 
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if (pol != null) {  | 
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pinfo = new PolicyInfo(pol, true);  | 
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                        } else { | 
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if (debug != null) {  | 
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debug.println("using sun.security.provider.PolicyFile");  | 
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}  | 
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pinfo = new PolicyInfo(polFile, true);  | 
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}  | 
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}  | 
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policy.set(pinfo);  | 
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}  | 
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return pinfo.policy;  | 
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}  | 
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}  | 
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return pi.policy;  | 
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}  | 
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    /** | 
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     * Sets the system-wide Policy object. This method first calls | 
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     * {@code SecurityManager.checkPermission} with a | 
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     * {@code SecurityPermission("setPolicy")} | 
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     * permission to ensure it's ok to set the Policy. | 
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     * | 
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     * @param p the new system Policy object. | 
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     * | 
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     * @throws SecurityException | 
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     *        if a security manager exists and its | 
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     *        {@code checkPermission} method doesn't allow | 
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     *        setting the Policy. | 
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     * | 
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     * @see SecurityManager#checkPermission(Permission) | 
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     * @see #getPolicy() | 
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     * | 
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*/  | 
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public static void setPolicy(Policy p)  | 
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    { | 
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SecurityManager sm = System.getSecurityManager();  | 
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if (sm != null) sm.checkPermission(  | 
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new SecurityPermission("setPolicy"));  | 
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if (p != null) {  | 
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initPolicy(p);  | 
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}  | 
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synchronized (Policy.class) {  | 
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policy.set(new PolicyInfo(p, p != null));  | 
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}  | 
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}  | 
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    /** | 
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     * Initialize superclass state such that a legacy provider can | 
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     * handle queries for itself. | 
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     * | 
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     * @since 1.4 | 
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*/  | 
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private static void initPolicy (final Policy p) {  | 
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/*  | 
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* A policy provider not on the bootclasspath could trigger  | 
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* security checks fulfilling a call to either Policy.implies  | 
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* or Policy.getPermissions. If this does occur the provider  | 
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* must be able to answer for it's own ProtectionDomain  | 
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* without triggering additional security checks, otherwise  | 
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* the policy implementation will end up in an infinite  | 
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* recursion.  | 
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*  | 
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* To mitigate this, the provider can collect it's own  | 
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* ProtectionDomain and associate a PermissionCollection while  | 
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* it is being installed. The currently installed policy  | 
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* provider (if there is one) will handle calls to  | 
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* Policy.implies or Policy.getPermissions during this  | 
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* process.  | 
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*  | 
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* This Policy superclass caches away the ProtectionDomain and  | 
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* statically binds permissions so that legacy Policy  | 
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* implementations will continue to function.  | 
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*/  | 
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ProtectionDomain policyDomain =  | 
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AccessController.doPrivileged(new PrivilegedAction<ProtectionDomain>() {  | 
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public ProtectionDomain run() {  | 
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return p.getClass().getProtectionDomain();  | 
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}  | 
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});  | 
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        /* | 
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         * Collect the permissions granted to this protection domain | 
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         * so that the provider can be security checked while processing | 
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         * calls to Policy.implies or Policy.getPermissions. | 
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*/  | 
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PermissionCollection policyPerms = null;  | 
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synchronized (p) {  | 
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if (p.pdMapping == null) {  | 
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p.pdMapping = new WeakHashMap<>();  | 
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}  | 
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}  | 
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if (policyDomain.getCodeSource() != null) {  | 
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Policy pol = policy.get().policy;  | 
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if (pol != null) {  | 
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policyPerms = pol.getPermissions(policyDomain);  | 
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}  | 
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if (policyPerms == null) { // assume it has all  | 
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policyPerms = new Permissions();  | 
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policyPerms.add(SecurityConstants.ALL_PERMISSION);  | 
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}  | 
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synchronized (p.pdMapping) {  | 
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                // cache of pd to permissions | 
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p.pdMapping.put(policyDomain.key, policyPerms);  | 
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}  | 
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}  | 
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return;  | 
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}  | 
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    /** | 
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     * Returns a Policy object of the specified type. | 
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     * | 
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     * <p> This method traverses the list of registered security providers, | 
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     * starting with the most preferred Provider. | 
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     * A new Policy object encapsulating the | 
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     * PolicySpi implementation from the first | 
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     * Provider that supports the specified type is returned. | 
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     * | 
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     * <p> Note that the list of registered providers may be retrieved via | 
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     * the {@link Security#getProviders() Security.getProviders()} method. | 
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     * | 
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     * @param type the specified Policy type.  See the Policy section in the | 
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     *    <a href= | 
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     *    "{@docRoot}/../technotes/guides/security/StandardNames.html#Policy"> | 
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     *    Java Cryptography Architecture Standard Algorithm Name Documentation</a> | 
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     *    for a list of standard Policy types. | 
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     * | 
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     * @param params parameters for the Policy, which may be null. | 
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     * | 
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     * @return the new Policy object. | 
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     * | 
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     * @exception SecurityException if the caller does not have permission | 
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     *          to get a Policy instance for the specified type. | 
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     * | 
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     * @exception NullPointerException if the specified type is null. | 
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     * | 
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     * @exception IllegalArgumentException if the specified parameters | 
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     *          are not understood by the PolicySpi implementation | 
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     *          from the selected Provider. | 
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     * | 
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     * @exception NoSuchAlgorithmException if no Provider supports a PolicySpi | 
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     *          implementation for the specified type. | 
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     * | 
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     * @see Provider | 
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     * @since 1.6 | 
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*/  | 
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public static Policy getInstance(String type, Policy.Parameters params)  | 
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throws NoSuchAlgorithmException {  | 
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checkPermission(type);  | 
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        try { | 
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GetInstance.Instance instance = GetInstance.getInstance("Policy",  | 
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PolicySpi.class,  | 
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type,  | 
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params);  | 
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return new PolicyDelegate((PolicySpi)instance.impl,  | 
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instance.provider,  | 
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type,  | 
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params);  | 
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} catch (NoSuchAlgorithmException nsae) {  | 
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return handleException(nsae);  | 
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}  | 
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}  | 
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    /** | 
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     * Returns a Policy object of the specified type. | 
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     * | 
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     * <p> A new Policy object encapsulating the | 
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     * PolicySpi implementation from the specified provider | 
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     * is returned.   The specified provider must be registered | 
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     * in the provider list. | 
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     * | 
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     * <p> Note that the list of registered providers may be retrieved via | 
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     * the {@link Security#getProviders() Security.getProviders()} method. | 
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     * | 
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     * @param type the specified Policy type.  See the Policy section in the | 
|
     *    <a href= | 
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     *    "{@docRoot}/../technotes/guides/security/StandardNames.html#Policy"> | 
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     *    Java Cryptography Architecture Standard Algorithm Name Documentation</a> | 
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     *    for a list of standard Policy types. | 
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     * | 
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     * @param params parameters for the Policy, which may be null. | 
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     * | 
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     * @param provider the provider. | 
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     * | 
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     * @return the new Policy object. | 
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     * | 
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     * @exception SecurityException if the caller does not have permission | 
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     *          to get a Policy instance for the specified type. | 
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     * | 
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     * @exception NullPointerException if the specified type is null. | 
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     * | 
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     * @exception IllegalArgumentException if the specified provider | 
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     *          is null or empty, | 
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     *          or if the specified parameters are not understood by | 
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     *          the PolicySpi implementation from the specified provider. | 
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     * | 
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     * @exception NoSuchProviderException if the specified provider is not | 
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     *          registered in the security provider list. | 
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     * | 
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     * @exception NoSuchAlgorithmException if the specified provider does not | 
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     *          support a PolicySpi implementation for the specified type. | 
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     * | 
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     * @see Provider | 
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     * @since 1.6 | 
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*/  | 
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public static Policy getInstance(String type,  | 
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Policy.Parameters params,  | 
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String provider)  | 
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throws NoSuchProviderException, NoSuchAlgorithmException {  | 
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if (provider == null || provider.length() == 0) {  | 
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throw new IllegalArgumentException("missing provider");  | 
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}  | 
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checkPermission(type);  | 
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        try { | 
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GetInstance.Instance instance = GetInstance.getInstance("Policy",  | 
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PolicySpi.class,  | 
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type,  | 
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params,  | 
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provider);  | 
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return new PolicyDelegate((PolicySpi)instance.impl,  | 
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instance.provider,  | 
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type,  | 
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params);  | 
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} catch (NoSuchAlgorithmException nsae) {  | 
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return handleException(nsae);  | 
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}  | 
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}  | 
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    /** | 
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     * Returns a Policy object of the specified type. | 
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     * | 
|
     * <p> A new Policy object encapsulating the | 
|
     * PolicySpi implementation from the specified Provider | 
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     * object is returned.  Note that the specified Provider object | 
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     * does not have to be registered in the provider list. | 
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     * | 
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     * @param type the specified Policy type.  See the Policy section in the | 
|
     *    <a href= | 
|
     *    "{@docRoot}/../technotes/guides/security/StandardNames.html#Policy"> | 
|
     *    Java Cryptography Architecture Standard Algorithm Name Documentation</a> | 
|
     *    for a list of standard Policy types. | 
|
     * | 
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     * @param params parameters for the Policy, which may be null. | 
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     * | 
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     * @param provider the Provider. | 
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     * | 
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     * @return the new Policy object. | 
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     * | 
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     * @exception SecurityException if the caller does not have permission | 
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     *          to get a Policy instance for the specified type. | 
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     * | 
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     * @exception NullPointerException if the specified type is null. | 
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     * | 
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     * @exception IllegalArgumentException if the specified Provider is null, | 
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     *          or if the specified parameters are not understood by | 
|
     *          the PolicySpi implementation from the specified Provider. | 
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     * | 
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     * @exception NoSuchAlgorithmException if the specified Provider does not | 
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     *          support a PolicySpi implementation for the specified type. | 
|
     * | 
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     * @see Provider | 
|
     * @since 1.6 | 
|
*/  | 
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public static Policy getInstance(String type,  | 
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Policy.Parameters params,  | 
|
Provider provider)  | 
|
throws NoSuchAlgorithmException {  | 
|
if (provider == null) {  | 
|
throw new IllegalArgumentException("missing provider");  | 
|
}  | 
|
checkPermission(type);  | 
|
        try { | 
|
GetInstance.Instance instance = GetInstance.getInstance("Policy",  | 
|
PolicySpi.class,  | 
|
type,  | 
|
params,  | 
|
provider);  | 
|
return new PolicyDelegate((PolicySpi)instance.impl,  | 
|
instance.provider,  | 
|
type,  | 
|
params);  | 
|
} catch (NoSuchAlgorithmException nsae) {  | 
|
return handleException(nsae);  | 
|
}  | 
|
}  | 
|
private static Policy handleException(NoSuchAlgorithmException nsae)  | 
|
throws NoSuchAlgorithmException {  | 
|
Throwable cause = nsae.getCause();  | 
|
if (cause instanceof IllegalArgumentException) {  | 
|
throw (IllegalArgumentException)cause;  | 
|
}  | 
|
throw nsae;  | 
|
}  | 
|
    /** | 
|
     * Return the Provider of this Policy. | 
|
     * | 
|
     * <p> This Policy instance will only have a Provider if it | 
|
     * was obtained via a call to {@code Policy.getInstance}. | 
|
     * Otherwise this method returns null. | 
|
     * | 
|
     * @return the Provider of this Policy, or null. | 
|
     * | 
|
     * @since 1.6 | 
|
*/  | 
|
public Provider getProvider() {  | 
|
return null;  | 
|
}  | 
|
    /** | 
|
     * Return the type of this Policy. | 
|
     * | 
|
     * <p> This Policy instance will only have a type if it | 
|
     * was obtained via a call to {@code Policy.getInstance}. | 
|
     * Otherwise this method returns null. | 
|
     * | 
|
     * @return the type of this Policy, or null. | 
|
     * | 
|
     * @since 1.6 | 
|
*/  | 
|
public String getType() {  | 
|
return null;  | 
|
}  | 
|
    /** | 
|
     * Return Policy parameters. | 
|
     * | 
|
     * <p> This Policy instance will only have parameters if it | 
|
     * was obtained via a call to {@code Policy.getInstance}. | 
|
     * Otherwise this method returns null. | 
|
     * | 
|
     * @return Policy parameters, or null. | 
|
     * | 
|
     * @since 1.6 | 
|
*/  | 
|
public Policy.Parameters getParameters() {  | 
|
return null;  | 
|
}  | 
|
    /** | 
|
     * Return a PermissionCollection object containing the set of | 
|
     * permissions granted to the specified CodeSource. | 
|
     * | 
|
     * <p> Applications are discouraged from calling this method | 
|
     * since this operation may not be supported by all policy implementations. | 
|
     * Applications should solely rely on the {@code implies} method | 
|
     * to perform policy checks.  If an application absolutely must call | 
|
     * a getPermissions method, it should call | 
|
     * {@code getPermissions(ProtectionDomain)}. | 
|
     * | 
|
     * <p> The default implementation of this method returns | 
|
     * Policy.UNSUPPORTED_EMPTY_COLLECTION.  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. | 
|
*/  | 
|
public PermissionCollection getPermissions(CodeSource codesource) {  | 
|
return Policy.UNSUPPORTED_EMPTY_COLLECTION;  | 
|
}  | 
|
    /** | 
|
     * Return a PermissionCollection object containing the set of | 
|
     * permissions granted to the specified ProtectionDomain. | 
|
     * | 
|
     * <p> Applications are discouraged from calling this method | 
|
     * since this operation may not be supported by all policy implementations. | 
|
     * Applications should rely on the {@code implies} method | 
|
     * to perform policy checks. | 
|
     * | 
|
     * <p> The default implementation of this method first retrieves | 
|
     * the permissions returned via {@code getPermissions(CodeSource)} | 
|
     * (the CodeSource is taken from the specified ProtectionDomain), | 
|
     * as well as the permissions located inside the specified ProtectionDomain. | 
|
     * All of these permissions are then combined and returned in a new | 
|
     * PermissionCollection object.  If {@code getPermissions(CodeSource)} | 
|
     * returns Policy.UNSUPPORTED_EMPTY_COLLECTION, then this method | 
|
     * returns the permissions contained inside the specified ProtectionDomain | 
|
     * in a new PermissionCollection object. | 
|
     * | 
|
     * <p> This method can be overridden if the policy implementation | 
|
     * supports returning 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. | 
|
     * | 
|
     * @since 1.4 | 
|
*/  | 
|
public PermissionCollection getPermissions(ProtectionDomain domain) {  | 
|
PermissionCollection pc = null;  | 
|
if (domain == null)  | 
|
return new Permissions();  | 
|
if (pdMapping == null) {  | 
|
initPolicy(this);  | 
|
}  | 
|
synchronized (pdMapping) {  | 
|
pc = pdMapping.get(domain.key);  | 
|
}  | 
|
if (pc != null) {  | 
|
Permissions perms = new Permissions();  | 
|
synchronized (pc) {  | 
|
for (Enumeration<Permission> e = pc.elements() ; e.hasMoreElements() ;) {  | 
|
perms.add(e.nextElement());  | 
|
}  | 
|
}  | 
|
return perms;  | 
|
}  | 
|
pc = getPermissions(domain.getCodeSource());  | 
|
if (pc == null || pc == UNSUPPORTED_EMPTY_COLLECTION) {  | 
|
pc = new Permissions();  | 
|
}  | 
|
addStaticPerms(pc, domain.getPermissions());  | 
|
return pc;  | 
|
}  | 
|
    /** | 
|
     * add static permissions to provided permission collection | 
|
*/  | 
|
private void addStaticPerms(PermissionCollection perms,  | 
|
PermissionCollection statics) {  | 
|
if (statics != null) {  | 
|
synchronized (statics) {  | 
|
Enumeration<Permission> e = statics.elements();  | 
|
while (e.hasMoreElements()) {  | 
|
perms.add(e.nextElement());  | 
|
}  | 
|
}  | 
|
}  | 
|
}  | 
|
    /** | 
|
     * Evaluates the global policy for the permissions granted to | 
|
     * the ProtectionDomain and tests whether the permission is | 
|
     * granted. | 
|
     * | 
|
     * @param domain the ProtectionDomain to test | 
|
     * @param permission the Permission object to be tested for implication. | 
|
     * | 
|
     * @return true if "permission" is a proper subset of a permission | 
|
     * granted to this ProtectionDomain. | 
|
     * | 
|
     * @see java.security.ProtectionDomain | 
|
     * @since 1.4 | 
|
*/  | 
|
public boolean implies(ProtectionDomain domain, Permission permission) {  | 
|
PermissionCollection pc;  | 
|
if (pdMapping == null) {  | 
|
initPolicy(this);  | 
|
}  | 
|
synchronized (pdMapping) {  | 
|
pc = pdMapping.get(domain.key);  | 
|
}  | 
|
if (pc != null) {  | 
|
return pc.implies(permission);  | 
|
}  | 
|
pc = getPermissions(domain);  | 
|
if (pc == null) {  | 
|
return false;  | 
|
}  | 
|
synchronized (pdMapping) {  | 
|
            // cache it | 
|
pdMapping.put(domain.key, pc);  | 
|
}  | 
|
return pc.implies(permission);  | 
|
}  | 
|
    /** | 
|
     * 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. | 
|
*/  | 
|
    public void refresh() { } | 
|
    /** | 
|
     * This subclass is returned by the getInstance calls.  All Policy calls | 
|
     * are delegated to the underlying PolicySpi. | 
|
*/  | 
|
private static class PolicyDelegate extends Policy {  | 
|
private PolicySpi spi;  | 
|
private Provider p;  | 
|
private String type;  | 
|
private Policy.Parameters params;  | 
|
private PolicyDelegate(PolicySpi spi, Provider p,  | 
|
String type, Policy.Parameters params) {  | 
|
this.spi = spi;  | 
|
this.p = p;  | 
|
this.type = type;  | 
|
this.params = params;  | 
|
}  | 
|
@Override public String getType() { return type; }  | 
|
@Override public Policy.Parameters getParameters() { return params; }  | 
|
@Override public Provider getProvider() { return p; }  | 
|
@Override  | 
|
public PermissionCollection getPermissions(CodeSource codesource) {  | 
|
return spi.engineGetPermissions(codesource);  | 
|
}  | 
|
@Override  | 
|
public PermissionCollection getPermissions(ProtectionDomain domain) {  | 
|
return spi.engineGetPermissions(domain);  | 
|
}  | 
|
@Override  | 
|
public boolean implies(ProtectionDomain domain, Permission perm) {  | 
|
return spi.engineImplies(domain, perm);  | 
|
}  | 
|
@Override  | 
|
        public void refresh() { | 
|
spi.engineRefresh();  | 
|
}  | 
|
}  | 
|
    /** | 
|
     * This represents a marker interface for Policy parameters. | 
|
     * | 
|
     * @since 1.6 | 
|
*/  | 
|
    public static interface Parameters { } | 
|
    /** | 
|
     * This class represents a read-only empty PermissionCollection object that | 
|
     * is returned from the {@code getPermissions(CodeSource)} and | 
|
     * {@code getPermissions(ProtectionDomain)} | 
|
     * methods in the Policy class when those operations are not | 
|
     * supported by the Policy implementation. | 
|
*/  | 
|
private static class UnsupportedEmptyCollection  | 
|
extends PermissionCollection {  | 
|
private static final long serialVersionUID = -8492269157353014774L;  | 
|
private Permissions perms;  | 
|
        /** | 
|
         * Create a read-only empty PermissionCollection object. | 
|
*/  | 
|
        public UnsupportedEmptyCollection() { | 
|
this.perms = new Permissions();  | 
|
perms.setReadOnly();  | 
|
}  | 
|
        /** | 
|
         * Adds a permission object to the current collection of permission | 
|
         * objects. | 
|
         * | 
|
         * @param permission the Permission object to add. | 
|
         * | 
|
         * @exception SecurityException - if this PermissionCollection object | 
|
         *                                has been marked readonly | 
|
*/  | 
|
@Override public void add(Permission permission) {  | 
|
perms.add(permission);  | 
|
}  | 
|
        /** | 
|
         * Checks to see if the specified permission is implied by the | 
|
         * collection of Permission objects held in this PermissionCollection. | 
|
         * | 
|
         * @param permission the Permission object to compare. | 
|
         * | 
|
         * @return true if "permission" is implied by the permissions in | 
|
         * the collection, false if not. | 
|
*/  | 
|
@Override public boolean implies(Permission permission) {  | 
|
return perms.implies(permission);  | 
|
}  | 
|
        /** | 
|
         * Returns an enumeration of all the Permission objects in the | 
|
         * collection. | 
|
         * | 
|
         * @return an enumeration of all the Permissions. | 
|
*/  | 
|
@Override public Enumeration<Permission> elements() {  | 
|
return perms.elements();  | 
|
}  | 
|
}  | 
|
}  |