How to use

getCategories

method

in

org.geotools.factory.FactoryRegistry

/**
 * Constructs a new registry for the specified categories.
 *
 * @param categories The categories.
 */
public FactoryRegistry(final Collection<Class<?>> categories) {
  super(categories.iterator());
  for (final Iterator<Class<?>> it=getCategories(); it.hasNext();) {
    if (needScanForPlugins == null) {
      needScanForPlugins = new HashSet<Class<?>>();
    }
    needScanForPlugins.add(it.next());
  }
}

/**
 * Sets or unsets a pairwise ordering between all factories meeting a criterion. For example
 * in the CRS framework ({@link org.geotools.referencing.FactoryFinder}), this is used for
 * setting ordering between all factories provided by two vendors, or for two authorities.
 * If one or both factories are not currently registered, or if the desired ordering is
 * already set/unset, nothing happens and false is returned.
 *
 * @param <T>      The class represented by the {@code base} argument.
 * @param base     The base category. Only categories {@linkplain Class#isAssignableFrom
 *                 assignable} to {@code base} will be processed.
 * @param set      {@code true} for setting the ordering, or {@code false} for unsetting.
 * @param service1 Filter for the preferred factory.
 * @param service2 Filter for the factory to which {@code service1} is preferred.
 * @return {@code true} if the ordering changed as a result of this call.
 */
public <T> boolean setOrdering(final Class<T> base, final boolean set,
                final Filter service1, final Filter service2)
{
  boolean done = false;
  for (final Iterator<Class<?>> categories=getCategories(); categories.hasNext();) {
    final Class<?> candidate = categories.next();
    if (base.isAssignableFrom(candidate)) {
      final Class<? extends T> category = candidate.asSubclass(base);
      done |= setOrUnsetOrdering(category, set, service1, service2);
    }
  }
  return done;
}

/**
 * Scans for factory plug-ins on the application class path. This method is
 * needed because the application class path can theoretically change, or
 * additional plug-ins may become available. Rather than re-scanning the
 * classpath on every invocation of the API, the class path is scanned
 * automatically only on the first invocation. Clients can call this
 * method to prompt a re-scan. Thus this method need only be invoked by
 * sophisticated applications which dynamically make new plug-ins
 * available at runtime.
 */
public void scanForPlugins() {
  final Set<ClassLoader> loaders = getClassLoaders();
  for (final Iterator<Class<?>> categories=getCategories(); categories.hasNext();) {
    final Class<?> category = categories.next();
    scanForPlugins(loaders, category);
  }
}

/**
 * Scans for factory plug-ins on the application class path. This method is
 * needed because the application class path can theoretically change, or
 * additional plug-ins may become available. Rather than re-scanning the
 * classpath on every invocation of the API, the class path is scanned
 * automatically only on the first invocation. Clients can call this
 * method to prompt a re-scan. Thus this method need only be invoked by
 * sophisticated applications which dynamically make new plug-ins
 * available at runtime.
 */
public void scanForPlugins() {
  final Set loaders = getClassLoaders();
  for (final Iterator categories=getCategories(); categories.hasNext();) {
    final Class category = (Class) categories.next();
    scanForPlugins(loaders, category);
  }
}

  return;
for (final Iterator<Class<?>> categories=getCategories(); categories.hasNext();) {
  final Class<?> category = categories.next();
  if (needScanForPlugins == null || !needScanForPlugins.contains(category)) {

for (final Iterator categories=getCategories(); categories.hasNext();) {
  final Class category = (Class) categories.next();
  if (base.isAssignableFrom(category)) {

  return;
for (final Iterator categories=getCategories(); categories.hasNext();) {
  final Class category = (Class) categories.next();
  if (getServiceProviders(category, false).hasNext()) {