CCM NG: SecuredCollection (not tested yet)

git-svn-id: https://svn.libreccm.org/ccm/ccm_ng@3750 8810af33-2d31-482b-a856-94f89814c4df

ccm-core/src/main/java/org/libreccm/security/SecuredCollection.java

@@ -0,0 +1,170 @@
+/*
+ * Copyright (C) 2015 LibreCCM Foundation.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301  USA
+ */
+package org.libreccm.security;
+
+import com.arsdigita.util.UncheckedWrapperException;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.libreccm.cdi.utils.CdiLookupException;
+import org.libreccm.cdi.utils.CdiUtil;
+import org.libreccm.core.CcmObject;
+
+import java.util.Collection;
+import java.util.Iterator;
+
+/**
+ *
+ * @author <a href="mailto:jens.pelzetter@googlemail.com">Jens Pelzetter</a>
+ *
+ * @param <E>
+ */
+public class SecuredCollection<E extends CcmObject> implements Collection<E> {
+
+    private static final Logger LOGGER = LogManager.getLogger(
+        SecuredCollection.class);
+
+    private final Collection<E> collection;
+
+    private final Class<E> clazz;
+
+    private final String privilege;
+
+    public SecuredCollection(final Collection<E> collection,
+                             final Class<E> clazz,
+                             final String privilege) {
+        this.collection = collection;
+        this.clazz = clazz;
+        this.privilege = privilege;
+    }
+
+    @Override
+    public int size() {
+        return collection.size();
+    }
+
+    @Override
+    public boolean isEmpty() {
+        return collection.isEmpty();
+    }
+
+    @Override
+    public boolean contains(final Object object) {
+        return collection.contains(object);
+    }
+
+    @Override
+    public Iterator<E> iterator() {
+        return new SecuredIterator<>(collection.iterator(), clazz, privilege);
+    }
+
+    @Override
+    @SuppressWarnings("unchecked")
+    public Object[] toArray() {
+        final PermissionChecker permissionChecker;
+        final CdiUtil cdiUtil = new CdiUtil();
+        try {
+            permissionChecker = cdiUtil.findBean(
+                PermissionChecker.class);
+        } catch (CdiLookupException ex) {
+            throw new UncheckedWrapperException(ex);
+        }
+
+        final Object[] objects = collection.toArray();
+        for (int i = 0; i < objects.length; i++) {
+            if (!permissionChecker.isPermitted(privilege, (E) objects[i])) {
+                objects[i] = generateAccessDeniedObject(clazz);
+            }
+        }
+        
+        return objects;
+    }
+
+    @Override
+    @SuppressWarnings("unchecked")
+    public <T> T[] toArray(final T[] array) {
+        final PermissionChecker permissionChecker;
+        final CdiUtil cdiUtil = new CdiUtil();
+        try {
+            permissionChecker = cdiUtil.findBean(
+                PermissionChecker.class);
+        } catch (CdiLookupException ex) {
+            throw new UncheckedWrapperException(ex);
+        }
+        
+        final T[] objects = collection.toArray(array);
+        for(int i = 0; i < objects.length; i++) {
+            if (!permissionChecker.isPermitted(privilege, (CcmObject) objects[i])) {
+                objects[i] = (T) generateAccessDeniedObject(clazz);
+            }
+        }
+        return objects;
+    }
+
+    @Override
+    public boolean add(final E element) {
+        return collection.add(element);
+    }
+
+    @Override
+    public boolean remove(final Object object) {
+        return collection.remove(object);
+    }
+
+    @Override
+    public boolean containsAll(final Collection<?> collection) {
+        return this.collection.containsAll(collection);
+    }
+
+    @Override
+    public boolean addAll(final Collection<? extends E> collection) {
+        return this.collection.addAll(collection);
+    }
+
+    @Override
+    public boolean removeAll(final Collection<?> collection) {
+        return this.collection.removeAll(collection);
+
+    }
+
+    @Override
+    public boolean retainAll(final Collection<?> collection) {
+        return this.collection.retainAll(collection);
+    }
+
+    @Override
+    public void clear() {
+        collection.clear();
+    }
+
+    private E generateAccessDeniedObject(final Class<E> clazz) {
+        final E placeholder;
+        try {
+            placeholder = clazz.newInstance();
+            placeholder.setDisplayName("Access denied");
+
+            return placeholder;
+        } catch (InstantiationException | IllegalAccessException ex) {
+            LOGGER.error(
+                "Failed to create placeholder object. Returing null.", ex);
+            return null;
+        }
+    }
+
+}