flex.messaging.services.messaging.Subtopic Maven / Gradle / Ivy
/*
* 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 flex.messaging.services.messaging;
import flex.messaging.services.ServiceException;
import java.util.StringTokenizer;
/**
* Represents a message destination subtopic. You are given instances of Subtopics
* as arguments to the MessagingAdapter.allowSubscribe and allowSend methods. These
* are used to implement your own authorization for the subscribe and send messages
* to specific subtopics.
*/
public class Subtopic
{
//--------------------------------------------------------------------------
//
// Constructor
//
//--------------------------------------------------------------------------
/**
* Constructor.
*
* @exclude
*
* @param subtopic The full subtopic string.
* @param separator The separator for tokenizing a hierarchical subtopic.
*/
public Subtopic(String subtopic, String separator)
{
this.subtopic = subtopic;
this.separator = separator;
// Subtopic cannot be zero length.
if (subtopic.length() == 0)
{
ServiceException se = new ServiceException();
se.setMessage(10554, new Object[] {subtopic});
throw se;
}
// Validate subtopic format if it contains a separator.
else if ((separator != null) && (subtopic.indexOf(separator) != -1))
{
hierarchical = true;
/*
* Each token must have non-zero length, meaning no leading or trailing
* separator or empty subtopics in between.
*/
if (subtopic.startsWith(separator) ||
subtopic.endsWith(separator) ||
(subtopic.indexOf(separator + separator) != -1))
{
ServiceException se = new ServiceException();
se.setMessage(10554, new Object[] {subtopic});
throw se;
}
/*
* If a token contains the SUBTOPIC_WILDCARD, that token may not
* contain any additional characters.
* I.e. chat.* is OK, chat.f* is not OK (assuming a separator of '.').
*/
StringTokenizer tokenizer = new StringTokenizer(subtopic, separator);
while (tokenizer.hasMoreTokens())
{
String token = tokenizer.nextToken();
if (token.indexOf(SUBTOPIC_WILDCARD) != -1)
{
if (!token.equals(SUBTOPIC_WILDCARD))
{
ServiceException se = new ServiceException();
se.setMessage(10554, new Object[] {subtopic});
throw se;
}
else
{
hasSubtopicWildcard = true;
}
}
}
}
// Non-hierarchical subtopics cannot contain subtopic wildcard unless
// that is the only value, "*", indicating a match for any subtopic.
else if (subtopic.indexOf(SUBTOPIC_WILDCARD) != -1)
{
if (!subtopic.equals(SUBTOPIC_WILDCARD))
{
ServiceException se = new ServiceException();
se.setMessage(10554, new Object[] {subtopic});
throw se;
}
else
{
hasSubtopicWildcard = true;
}
}
}
//--------------------------------------------------------------------------
//
// Constants
//
//--------------------------------------------------------------------------
/**
* The wildcard token for hierarchical subtopics.
*/
public static final String SUBTOPIC_WILDCARD = "*";
//--------------------------------------------------------------------------
//
// Variables
//
//--------------------------------------------------------------------------
/**
* The full subtopic value.
*/
private String subtopic;
/**
* The separator used if the subtopic is hierarchical.
*/
private String separator;
/**
* Flag to store whether the subtopic is hierarchical.
*/
private boolean hierarchical;
/**
* Flag to store whether the subtopic contains subtopic wildcards.
*/
private boolean hasSubtopicWildcard;
//--------------------------------------------------------------------------
//
// Methods
//
//--------------------------------------------------------------------------
/**
* Returns true if the subtopic contains a hierarchical subtopic wildcard.
*
* @return true if the subtopic contains a hierarchical subtopic wildcard,
* otherwise false.
*/
public boolean containsSubtopicWildcard()
{
return hasSubtopicWildcard;
}
/**
* Override of equals.
*
* @param other The object to compare against.
* @return true if other equals to this; false otherwise;
*/
public boolean equals(Object other)
{
if (!(other instanceof Subtopic))
return false;
Subtopic otherSubtopic = (Subtopic) other;
if (subtopic.equals(otherSubtopic.subtopic) &&
((separator == null && otherSubtopic.separator == null) || (separator != null && separator.equals(otherSubtopic.separator))))
{
return true;
}
else
{
return false;
}
}
/**
* Returns the separator used to create this Subtopic instance.
* This value may be null.
*
* @return The separator used to create this Subtopic instance.
*/
public String getSeparator()
{
return separator;
}
/**
* Returns the subtopic value used to create this Subtopic instance.
*
* @return The subtopic value used to create this Subtopic instance.
*/
public String getValue()
{
return subtopic;
}
/**
* Override of hashCode. Hash using the subtopic String rather than the object's address.
*
* @return The hashCode.
*/
public int hashCode()
{
return subtopic.hashCode();
}
/**
* Returns true is the subtopic is hierarchical.
*
* @return true if the subtopic is hierarchical, otherwise false.
*/
public boolean isHierarchical()
{
return hierarchical;
}
/**
* Matches the passed subtopic against this subtopic.
* If neither subtopic contains a wildcard they must literally match.
* If one or the other contains a wildcard they may match.
* "chatrooms.*" will match "chatrooms.lobby" or "chatrooms.us.ca" but will
* not match "chatrooms" (assuming a subtopic separator of ".").
* "chatrooms.*.ca" will match "chatrooms.us.ca" but not "chatrooms.us.ma".
*
* @param other The other subtopic to match against this subtopic.
* @return true if they match, otherwise false.
*/
public boolean matches(Subtopic other)
{
// If neither contain a wildcard, match them as simple Strings.
if (!hasSubtopicWildcard && !other.hasSubtopicWildcard)
{
return (subtopic.equals(other.subtopic)) ? true : false;
}
// Otherwise, this subtopic or the other contains a wildcard.
else
{
// If both are hierarchical but use different separators - don't match.
if (hierarchical && other.hierarchical && !separator.equals(other.separator))
return false;
StringTokenizer t1 = new StringTokenizer(subtopic, separator);
StringTokenizer t2 = new StringTokenizer(other.subtopic, other.separator);
int n = t1.countTokens();
int difference = n - t2.countTokens();
String tok1 = null;
String tok2 = null;
boolean matchToken;
while (n-- > 0)
{
tok1 = t1.nextToken();
if (tok1.equals(SUBTOPIC_WILDCARD))
matchToken = false;
else
matchToken = true;
if (t2.hasMoreTokens())
{
tok2 = t2.nextToken();
if (tok2.equals(SUBTOPIC_WILDCARD))
continue;
}
else
{
break; // No more tokens to compare.
}
if (matchToken && !tok1.equals(tok2))
return false;
}
if (difference == 0)
return true;
else if ((difference < 0) && tok1.equals(SUBTOPIC_WILDCARD))
return true;
else if ((difference > 0) && tok2.equals(SUBTOPIC_WILDCARD))
return true;
else
return false;
}
}
/**
* Override of toString.
*
* @return The subtopic string.
*/
public String toString()
{
return subtopic;
}
}
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