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 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package java.security;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamField;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CopyOnWriteArrayList;

/**
 * A UnresolvedPermissionCollection stores a collection
 * of UnresolvedPermission permissions.
 *
 * @see java.security.Permission
 * @see java.security.Permissions
 * @see java.security.UnresolvedPermission
 *
 *
 * @author Roland Schemers
 * @since 1.2
 *
 * @serial include
 */

final class UnresolvedPermissionCollection
extends PermissionCollection
implements java.io.Serializable
{
 /**
 * Key is permission type, value is a list of the UnresolvedPermissions
 * of the same type.
 * Not serialized; see serialization section at end of class.
 */
 private transient ConcurrentHashMap<String, List<UnresolvedPermission>> perms;

 /**
 * Create an empty UnresolvedPermissionCollection object.
 *
 */
 public UnresolvedPermissionCollection() {
 perms = new ConcurrentHashMap<>(11);
 }

 /**
 * Adds a permission to this UnresolvedPermissionCollection.
 * The key for the hash is the unresolved permission's type (class) name.
 *
 * @param permission the Permission object to add.
 */
 @Override
 public void add(Permission permission) {
 if (! (permission instanceof UnresolvedPermission))
 throw new IllegalArgumentException("invalid permission: "+
 permission);
 UnresolvedPermission up = (UnresolvedPermission) permission;

 // Add permission to map. NOTE: cannot use lambda for
 // remappingFunction parameter until JDK-8076596 is fixed.
 perms.compute(up.getName(),
 new java.util.function.BiFunction<>() {
 @Override
 public List<UnresolvedPermission> apply(String key,
 List<UnresolvedPermission> oldValue) {
 if (oldValue == null) {
 List<UnresolvedPermission> v =
 new CopyOnWriteArrayList<>();
 v.add(up);
 return v;
 } else {
 oldValue.add(up);
 return oldValue;
 }
 }
 }
 );
 }

 /**
 * get any unresolved permissions of the same type as p,
 * and return the List containing them.
 */
 List<UnresolvedPermission> getUnresolvedPermissions(Permission p) {
 return perms.get(p.getClass().getName());
 }

 /**
 * always returns false for unresolved permissions
 *
 */
 @Override
 public boolean implies(Permission permission) {
 return false;
 }

 /**
 * Returns an enumeration of all the UnresolvedPermission lists in the
 * container.
 *
 * @return an enumeration of all the UnresolvedPermission objects.
 */
 @Override
 public Enumeration<Permission> elements() {
 List<Permission> results =
 new ArrayList<>(); // where results are stored

 // Get iterator of Map values (which are lists of permissions)
 for (List<UnresolvedPermission> l : perms.values()) {
 results.addAll(l);
 }

 return Collections.enumeration(results);
 }

 private static final long serialVersionUID = -7176153071733132400L;

 // Need to maintain serialization interoperability with earlier releases,
 // which had the serializable field:
 // private Hashtable permissions; // keyed on type

 /**
 * @serialField permissions java.util.Hashtable
 * A table of the UnresolvedPermissions keyed on type, value is Vector
 * of permissions
 */
 private static final ObjectStreamField[] serialPersistentFields = {
 new ObjectStreamField("permissions", Hashtable.class),
 };

 /**
 * @serialData Default field.
 */
 /*
 * Writes the contents of the perms field out as a Hashtable
 * in which the values are Vectors for
 * serialization compatibility with earlier releases.
 */
 private void writeObject(ObjectOutputStream out) throws IOException {
 // Don't call out.defaultWriteObject()

 // Copy perms into a Hashtable
 Hashtable<String, Vector<UnresolvedPermission>> permissions =
 new Hashtable<>(perms.size()*2);

 // Convert each entry (List) into a Vector
 Set<Map.Entry<String, List<UnresolvedPermission>>> set = perms.entrySet();
 for (Map.Entry<String, List<UnresolvedPermission>> e : set) {
 // Convert list into Vector
 List<UnresolvedPermission> list = e.getValue();
 Vector<UnresolvedPermission> vec = new Vector<>(list);

 // Add to Hashtable being serialized
 permissions.put(e.getKey(), vec);
 }

 // Write out serializable fields
 ObjectOutputStream.PutField pfields = out.putFields();
 pfields.put("permissions", permissions);
 out.writeFields();
 }

 /*
 * Reads in a Hashtable in which the values are Vectors of
 * UnresolvedPermissions and saves them in the perms field.
 */
 private void readObject(ObjectInputStream in) throws IOException,
 ClassNotFoundException {
 // Don't call defaultReadObject()

 // Read in serialized fields
 ObjectInputStream.GetField gfields = in.readFields();

 // Get permissions
 @SuppressWarnings("unchecked")
 // writeObject writes a Hashtable<String, Vector<UnresolvedPermission>>
 // for the permissions key, so this cast is safe, unless the data is corrupt.
 Hashtable<String, Vector<UnresolvedPermission>> permissions =
 (Hashtable<String, Vector<UnresolvedPermission>>)
 gfields.get("permissions", null);
 perms = new ConcurrentHashMap<>(permissions.size()*2);

 // Convert each entry (Vector) into a List
 Set<Map.Entry<String, Vector<UnresolvedPermission>>> set = permissions.entrySet();
 for (Map.Entry<String, Vector<UnresolvedPermission>> e : set) {
 // Convert Vector into ArrayList
 Vector<UnresolvedPermission> vec = e.getValue();
 List<UnresolvedPermission> list = new CopyOnWriteArrayList<>(vec);

 // Add to Hashtable being serialized
 perms.put(e.getKey(), list);
 }
 }
}