org.wildfly.security.permission.SimpleActionBitsPermissionCollection Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* JBoss, Home of Professional Open Source.
* Copyright 2016 Red Hat, Inc., and individual contributors
* as indicated by the @author tags.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.wildfly.security.permission;
import java.security.Permission;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.concurrent.atomic.AtomicReference;
import org.wildfly.security.util.ArrayIterator;
/**
* A trivially simple permission collection, suitable as a default for most permission types (though probably not as efficient
* as a specialized type in many cases).
*
* @author David M. Lloyd
*/
public final class SimpleActionBitsPermissionCollection extends AbstractPermissionCollection {
private static final AbstractActionSetPermission[] NO_PERMS = new AbstractActionSetPermission[0];
private final AtomicReference[]> permissionsRef = new AtomicReference<>(NO_PERMS);
/**
* Construct a new instance.
*
* @param sourcePermission the source permission for this collection (must not be {@code null})
*/
public SimpleActionBitsPermissionCollection(final AbstractActionSetPermission sourcePermission) {
super(sourcePermission);
}
public int size() {
return permissionsRef.get().length;
}
@Override
protected void doAdd(final AbstractPermission permission) {
if (permission instanceof AbstractActionSetPermission) {
doAdd((AbstractActionSetPermission) permission);
}
throw ElytronMessages.log.invalidPermissionType(AbstractActionSetPermission.class, permission);
}
/**
* Adds a permission.
*
* @param permission the non-{@code null} permission
*/
protected void doAdd(final AbstractActionSetPermission permission) {
AbstractActionSetPermission[] oldVal, readVal, newVal;
int count;
final AtomicReference[]> permissionsRef = this.permissionsRef;
do {
readVal = permissionsRef.get();
count = 0;
do {
oldVal = readVal;
AbstractActionSetPermission merged = permission;
retry: for (;;) {
for (AbstractActionSetPermission test : oldVal) {
if (test.implies(merged)) {
// fail fast
return;
}
if (test.nameEquals(merged)) {
// combine
merged = merged.withActionBits(permission.getActionBits());
// test again with merged permission
count = 0;
continue retry;
}
if (! merged.implies(test)) {
// prepare to skip any permissions that are obviated by this one
count ++;
}
}
break;
}
// see if it's still what we expect before we commit to the possibly expensive update...
readVal = permissionsRef.get();
} while (readVal != oldVal);
newVal = new AbstractActionSetPermission[count + 1];
int i = 0;
for (AbstractActionSetPermission test : oldVal) {
if (! permission.implies(test)) {
newVal[i++] = test;
}
}
newVal[i] = permission;
} while (! permissionsRef.compareAndSet(oldVal, newVal));
}
public boolean implies(final Permission permission) {
for (Permission test : permissionsRef.get()) {
if (test.implies(permission)) {
return true;
}
}
return false;
}
public Iterator iterator() {
return new ArrayIterator(permissionsRef.get());
}
public Enumeration elements() {
return new ArrayIterator(permissionsRef.get());
}
}