org.ocpsoft.rewrite.servlet.config.encodequery.HashCodeChecksumStrategy Maven / Gradle / Ivy
/*
* Copyright 2011 Lincoln Baxter, III
*
* 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.ocpsoft.rewrite.servlet.config.encodequery;
/**
* {@link ChecksumStrategy} based on Java {@link String#hashCode()} equality
*
* @author Lincoln Baxter, III
*/
public class HashCodeChecksumStrategy implements ChecksumStrategy
{
private static final String CHECKSUM_DELIM = "#";
@Override
public boolean checksumValid(final String token)
{
if (token.contains(CHECKSUM_DELIM))
{
int hashCode = token.substring(token.indexOf(CHECKSUM_DELIM) + 1).hashCode();
Integer storedHashCode;
try {
storedHashCode = Integer.valueOf(token.substring(0, token.indexOf(CHECKSUM_DELIM)));
}
catch (NumberFormatException e) {
return false;
}
return hashCode == storedHashCode;
}
return false;
}
@Override
public String embedChecksum(final String token)
{
String result = token.hashCode() + CHECKSUM_DELIM + token;
return result;
}
@Override
public String removeChecksum(final String token)
{
String result = token.substring(token.indexOf(CHECKSUM_DELIM) + 1);
return result;
}
}