private void rotateTokens(HttpServletRequest request) {
HttpSession session = request.getSession(true);
/** rotate master token * */
String tokenFromSession = null;
try {
tokenFromSession = RandomGenerator.generateRandomId(getPrng(), getTokenLength());
} catch (Exception e) {
throw new RuntimeException(
String.format("unable to generate the random token - %s", e.getLocalizedMessage()), e);
}
session.setAttribute(getSessionKey(), tokenFromSession);
/** rotate page token * */
if (isTokenPerPageEnabled()) {
@SuppressWarnings("unchecked")
Map<String, String> pageTokens =
(Map<String, String>) session.getAttribute(CsrfGuard.PAGE_TOKENS_KEY);
try {
pageTokens.put(
request.getRequestURI(), RandomGenerator.generateRandomId(getPrng(), getTokenLength()));
} catch (Exception e) {
throw new RuntimeException(
String.format("unable to generate the random token - %s", e.getLocalizedMessage()), e);
}
}
}
/**
* Operate on the given chromosome with the given mutation rate.
*
* @param a_chrom chromosome to operate
* @param a_rate mutation rate
* @param a_generator random generator to use (must not be null)
* @return mutated chromosome of null if no mutation has occured.
* @author Audrius Meskauskas
* @author Florian Hafner
* @since 3.3.2
*/
protected IChromosome operate(
final IChromosome a_chrom, final int a_rate, final RandomGenerator a_generator) {
IChromosome chromosome = null;
// ----------------------------------------
for (int j = m_startOffset; j < a_chrom.size(); j++) {
// Ensure probability of 1/currentRate for applying mutation.
// ----------------------------------------------------------
if (a_generator.nextInt(a_rate) == 0) {
if (chromosome == null) {
chromosome = (IChromosome) a_chrom.clone();
// In case monitoring is active, support it.
// -----------------------------------------
if (m_monitorActive) {
chromosome.setUniqueIDTemplate(a_chrom.getUniqueID(), 1);
}
}
Gene[] genes = chromosome.getGenes();
if (m_range == 0) {
m_range = genes.length;
}
Gene[] mutated = operate(a_generator, j, genes);
// setGenes is not required for this operator, but it may
// be needed for the derived operators.
// ------------------------------------------------------
try {
chromosome.setGenes(mutated);
} catch (InvalidConfigurationException cex) {
throw new Error("Gene type not allowed by constraint checker", cex);
}
}
}
return chromosome;
}
/**
* Create page token if it doesn't exist.
*
* @param pageTokens A map of tokens. If token doesn't exist it will be added.
* @param uri The key for the tokens.
*/
private void createPageToken(Map<String, String> pageTokens, String uri) {
if (pageTokens == null) return;
/** create token if it does not exist * */
if (pageTokens.containsKey(uri)) return;
try {
pageTokens.put(uri, RandomGenerator.generateRandomId(getPrng(), getTokenLength()));
} catch (Exception e) {
throw new RuntimeException(
String.format("unable to generate the random token - %s", e.getLocalizedMessage()), e);
}
}
public void updateToken(HttpSession session) {
String tokenValue = (String) session.getAttribute(getSessionKey());
/** Generate a new token and store it in the session. * */
if (tokenValue == null) {
try {
tokenValue = RandomGenerator.generateRandomId(getPrng(), getTokenLength());
} catch (Exception e) {
throw new RuntimeException(
String.format("unable to generate the random token - %s", e.getLocalizedMessage()), e);
}
session.setAttribute(getSessionKey(), tokenValue);
}
}
/**
* Operate on the given array of genes. This method is only called when it is already clear that
* the mutation must occur under the given mutation rate.
*
* @param a_generator a random number generator that may be needed to perform a mutation
* @param a_target_gene an index of gene in the chromosome that will mutate
* @param a_genes the array of all genes in the chromosome
* @return the mutated gene array
* @author Florian Hafner
* @since 3.3.2
*/
protected Gene[] operate(
final RandomGenerator a_generator, final int a_target_gene, final Gene[] a_genes) {
// Other needs to be an integer that is within the range of the subject
// target gene.
int rand = a_generator.nextInt(2 * m_range);
int other = (a_target_gene - m_range) + rand;
if (other < 0) {
other = 0;
}
if (other >= a_genes.length) {
other = a_genes.length - 1; // Index is -1 of length
}
Gene t = a_genes[a_target_gene];
a_genes[a_target_gene] = a_genes[other];
a_genes[other] = t;
if (m_monitorActive) {
a_genes[a_target_gene].setUniqueIDTemplate(a_genes[other].getUniqueID(), 1);
a_genes[other].setUniqueIDTemplate(a_genes[a_target_gene].getUniqueID(), 1);
}
return a_genes;
}