/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.felix.connect.felix.framework.capabilityset;
import java.lang.reflect.Array;
import java.lang.reflect.Constructor;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.TreeMap;
import org.apache.felix.connect.felix.framework.util.StringComparator;
import org.osgi.framework.wiring.BundleCapability;
public class CapabilitySet
{
private final Map<String, Map<Object, Set<BundleCapability>>> m_indices;
private final Set<BundleCapability> m_capSet = new HashSet<BundleCapability>();
public CapabilitySet(List<String> indexProps, boolean caseSensitive)
{
m_indices = (caseSensitive)
? new TreeMap<String, Map<Object, Set<BundleCapability>>>()
: new TreeMap<String, Map<Object, Set<BundleCapability>>>(
new StringComparator(false));
for (int i = 0; (indexProps != null) && (i < indexProps.size()); i++)
{
m_indices.put(
indexProps.get(i), new HashMap<Object, Set<BundleCapability>>());
}
}
public void addCapability(BundleCapability cap)
{
m_capSet.add(cap);
// Index capability.
for (Entry<String, Map<Object, Set<BundleCapability>>> entry : m_indices.entrySet())
{
Object value = cap.getAttributes().get(entry.getKey());
if (value != null)
{
if (value.getClass().isArray())
{
value = convertArrayToList(value);
}
Map<Object, Set<BundleCapability>> index = entry.getValue();
if (value instanceof Collection)
{
Collection c = (Collection) value;
for (Object o : c)
{
indexCapability(index, cap, o);
}
}
else
{
indexCapability(index, cap, value);
}
}
}
}
private void indexCapability(
Map<Object, Set<BundleCapability>> index, BundleCapability cap, Object capValue)
{
Set<BundleCapability> caps = index.get(capValue);
if (caps == null)
{
caps = new HashSet<BundleCapability>();
index.put(capValue, caps);
}
caps.add(cap);
}
public void removeCapability(BundleCapability cap)
{
if (m_capSet.remove(cap))
{
for (Entry<String, Map<Object, Set<BundleCapability>>> entry : m_indices.entrySet())
{
Object value = cap.getAttributes().get(entry.getKey());
if (value != null)
{
if (value.getClass().isArray())
{
value = convertArrayToList(value);
}
Map<Object, Set<BundleCapability>> index = entry.getValue();
if (value instanceof Collection)
{
Collection c = (Collection) value;
for (Object o : c)
{
deindexCapability(index, cap, o);
}
}
else
{
deindexCapability(index, cap, value);
}
}
}
}
}
private void deindexCapability(
Map<Object, Set<BundleCapability>> index, BundleCapability cap, Object value)
{
Set<BundleCapability> caps = index.get(value);
if (caps != null)
{
caps.remove(cap);
if (caps.isEmpty())
{
index.remove(value);
}
}
}
public Set<BundleCapability> match(SimpleFilter sf, boolean obeyMandatory)
{
Set<BundleCapability> matches = match(m_capSet, sf);
return matches;
/* return (obeyMandatory)
? matchMandatory(matches, sf)
: matches;*/
}
private Set<BundleCapability> match(Set<BundleCapability> caps, SimpleFilter sf)
{
Set<BundleCapability> matches = new HashSet<BundleCapability>();
if (sf.getOperation() == SimpleFilter.MATCH_ALL)
{
matches.addAll(caps);
}
else if (sf.getOperation() == SimpleFilter.AND)
{
// Evaluate each subfilter against the remaining capabilities.
// For AND we calculate the intersection of each subfilter.
// We can short-circuit the AND operation if there are no
// remaining capabilities.
List<SimpleFilter> sfs = (List<SimpleFilter>) sf.getValue();
for (int i = 0; (caps.size() > 0) && (i < sfs.size()); i++)
{
matches = match(caps, sfs.get(i));
caps = matches;
}
}
else if (sf.getOperation() == SimpleFilter.OR)
{
// Evaluate each subfilter against the remaining capabilities.
// For OR we calculate the union of each subfilter.
List<SimpleFilter> sfs = (List<SimpleFilter>) sf.getValue();
for (int i = 0; i < sfs.size(); i++)
{
matches.addAll(match(caps, sfs.get(i)));
}
}
else if (sf.getOperation() == SimpleFilter.NOT)
{
// Evaluate each subfilter against the remaining capabilities.
// For OR we calculate the union of each subfilter.
matches.addAll(caps);
List<SimpleFilter> sfs = (List<SimpleFilter>) sf.getValue();
for (int i = 0; i < sfs.size(); i++)
{
matches.removeAll(match(caps, sfs.get(i)));
}
}
else
{
Map<Object, Set<BundleCapability>> index = m_indices.get(sf.getName());
if ((sf.getOperation() == SimpleFilter.EQ) && (index != null))
{
Set<BundleCapability> existingCaps = index.get(sf.getValue());
if (existingCaps != null)
{
matches.addAll(existingCaps);
matches.retainAll(caps);
}
}
else
{
for (Iterator<BundleCapability> it = caps.iterator(); it.hasNext(); )
{
BundleCapability cap = it.next();
Object lhs = cap.getAttributes().get(sf.getName());
if (lhs != null)
{
if (compare(lhs, sf.getValue(), sf.getOperation()))
{
matches.add(cap);
}
}
}
}
}
return matches;
}
/* public static boolean matches(BundleCapability cap, SimpleFilter sf)
{
return matchesInternal(cap, sf) && matchMandatory(cap, sf);
}
*/
private static boolean matchesInternal(BundleCapability cap, SimpleFilter sf)
{
boolean matched = true;
if (sf.getOperation() == SimpleFilter.MATCH_ALL)
{
matched = true;
}
else if (sf.getOperation() == SimpleFilter.AND)
{
// Evaluate each subfilter against the remaining capabilities.
// For AND we calculate the intersection of each subfilter.
// We can short-circuit the AND operation if there are no
// remaining capabilities.
List<SimpleFilter> sfs = (List<SimpleFilter>) sf.getValue();
for (int i = 0; matched && (i < sfs.size()); i++)
{
matched = matchesInternal(cap, sfs.get(i));
}
}
else if (sf.getOperation() == SimpleFilter.OR)
{
// Evaluate each subfilter against the remaining capabilities.
// For OR we calculate the union of each subfilter.
matched = false;
List<SimpleFilter> sfs = (List<SimpleFilter>) sf.getValue();
for (int i = 0; !matched && (i < sfs.size()); i++)
{
matched = matchesInternal(cap, sfs.get(i));
}
}
else if (sf.getOperation() == SimpleFilter.NOT)
{
// Evaluate each subfilter against the remaining capabilities.
// For OR we calculate the union of each subfilter.
List<SimpleFilter> sfs = (List<SimpleFilter>) sf.getValue();
for (int i = 0; i < sfs.size(); i++)
{
matched = !(matchesInternal(cap, sfs.get(i)));
}
}
else
{
matched = false;
Object lhs = cap.getAttributes().get(sf.getName());
if (lhs != null)
{
matched = compare(lhs, sf.getValue(), sf.getOperation());
}
}
return matched;
}
/* private static Set<BundleCapability> matchMandatory(
Set<BundleCapability> caps, SimpleFilter sf)
{
for (Iterator<BundleCapability> it = caps.iterator(); it.hasNext(); )
{
BundleCapability cap = it.next();
if (!matchMandatory(cap, sf))
{
it.remove();
}
}
return caps;
}
private static boolean matchMandatory(BundleCapability cap, SimpleFilter sf)
{
Map<String, Object> attrs = cap.getAttributes();
for (Entry<String, Object> entry : attrs.entrySet())
{
if (((BundleCapability) cap).isAttributeMandatory(entry.getKey())
&& !matchMandatoryAttrbute(entry.getKey(), sf))
{
return false;
}
}
return true;
}
private static boolean matchMandatoryAttrbute(String attrName, SimpleFilter sf)
{
if ((sf.getName() != null) && sf.getName().equals(attrName))
{
return true;
}
else if (sf.getOperation() == SimpleFilter.AND)
{
List list = (List) sf.getValue();
for (int i = 0; i < list.size(); i++)
{
SimpleFilter sf2 = (SimpleFilter) list.get(i);
if ((sf2.getName() != null)
&& sf2.getName().equals(attrName))
{
return true;
}
}
}
return false;
}*/
private static final Class<?>[] STRING_CLASS = new Class[] { String.class };
private static boolean compare(Object lhs, Object rhsUnknown, int op)
{
if (lhs == null)
{
return false;
}
// If this is a PRESENT operation, then just return true immediately
// since we wouldn't be here if the attribute wasn't present.
if (op == SimpleFilter.PRESENT)
{
return true;
}
// If the type is comparable, then we can just return the
// result immediately.
if (lhs instanceof Comparable)
{
// Spec says SUBSTRING is false for all types other than string.
if ((op == SimpleFilter.SUBSTRING) && !(lhs instanceof String))
{
return false;
}
Object rhs;
if (op == SimpleFilter.SUBSTRING)
{
rhs = rhsUnknown;
}
else
{
try
{
rhs = coerceType(lhs, (String) rhsUnknown);
}
catch (Exception ex)
{
return false;
}
}
switch (op)
{
case SimpleFilter.EQ:
try
{
return (((Comparable) lhs).compareTo(rhs) == 0);
}
catch (Exception ex)
{
return false;
}
case SimpleFilter.GTE:
try
{
return (((Comparable) lhs).compareTo(rhs) >= 0);
}
catch (Exception ex)
{
return false;
}
case SimpleFilter.LTE:
try
{
return (((Comparable) lhs).compareTo(rhs) <= 0);
}
catch (Exception ex)
{
return false;
}
case SimpleFilter.APPROX:
return compareApproximate(((Comparable) lhs), rhs);
case SimpleFilter.SUBSTRING:
return SimpleFilter.compareSubstring((List<String>) rhs, (String) lhs);
default:
throw new RuntimeException(
"Unknown comparison operator: " + op);
}
}
// Booleans do not implement comparable, so special case them.
else if (lhs instanceof Boolean)
{
Object rhs;
try
{
rhs = coerceType(lhs, (String) rhsUnknown);
}
catch (Exception ex)
{
return false;
}
switch (op)
{
case SimpleFilter.EQ:
case SimpleFilter.GTE:
case SimpleFilter.LTE:
case SimpleFilter.APPROX:
return (lhs.equals(rhs));
default:
throw new RuntimeException(
"Unknown comparison operator: " + op);
}
}
// If the LHS is not a comparable or boolean, check if it is an
// array. If so, convert it to a list so we can treat it as a
// collection.
if (lhs.getClass().isArray())
{
lhs = convertArrayToList(lhs);
}
// If LHS is a collection, then call compare() on each element
// of the collection until a match is found.
if (lhs instanceof Collection)
{
for (Iterator iter = ((Collection) lhs).iterator(); iter.hasNext();)
{
if (compare(iter.next(), rhsUnknown, op))
{
return true;
}
}
return false;
}
// Spec says SUBSTRING is false for all types other than string.
if ((op == SimpleFilter.SUBSTRING) && !(lhs instanceof String))
{
return false;
}
// Since we cannot identify the LHS type, then we can only perform
// equality comparison.
try
{
return lhs.equals(coerceType(lhs, (String) rhsUnknown));
}
catch (Exception ex)
{
return false;
}
}
private static boolean compareApproximate(Object lhs, Object rhs)
{
if (rhs instanceof String)
{
return removeWhitespace((String) lhs)
.equalsIgnoreCase(removeWhitespace((String) rhs));
}
else if (rhs instanceof Character)
{
return Character.toLowerCase(((Character) lhs))
== Character.toLowerCase(((Character) rhs));
}
return lhs.equals(rhs);
}
private static String removeWhitespace(String s)
{
StringBuffer sb = new StringBuffer(s.length());
for (int i = 0; i < s.length(); i++)
{
if (!Character.isWhitespace(s.charAt(i)))
{
sb.append(s.charAt(i));
}
}
return sb.toString();
}
private static Object coerceType(Object lhs, String rhsString) throws Exception
{
// If the LHS expects a string, then we can just return
// the RHS since it is a string.
if (lhs.getClass() == rhsString.getClass())
{
return rhsString;
}
// Try to convert the RHS type to the LHS type by using
// the string constructor of the LHS class, if it has one.
Object rhs = null;
try
{
// The Character class is a special case, since its constructor
// does not take a string, so handle it separately.
if (lhs instanceof Character)
{
rhs = new Character(rhsString.charAt(0));
}
else
{
// Spec says we should trim number types.
if ((lhs instanceof Number) || (lhs instanceof Boolean))
{
rhsString = rhsString.trim();
}
Constructor ctor = lhs.getClass().getConstructor(STRING_CLASS);
ctor.setAccessible(true);
rhs = ctor.newInstance(new Object[] { rhsString });
}
}
catch (Exception ex)
{
throw new Exception(
"Could not instantiate class "
+ lhs.getClass().getName()
+ " from string constructor with argument '"
+ rhsString + "' because " + ex);
}
return rhs;
}
/**
* This is an ugly utility method to convert an array of primitives to an
* array of primitive wrapper objects. This method simplifies processing
* LDAP filters since the special case of primitive arrays can be ignored.
*
* @param array
* An array of primitive types.
* @return An corresponding array using pritive wrapper objects.
**/
private static List convertArrayToList(Object array)
{
int len = Array.getLength(array);
List list = new ArrayList(len);
for (int i = 0; i < len; i++)
{
list.add(Array.get(array, i));
}
return list;
}
}