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org.apache.tapestry5.ioc.internal.util
public final class: IdAllocator [javadoc | source]

java.lang.Object
   org.apache.tapestry5.ioc.internal.util.IdAllocator

Used to "uniquify" names within a given context. A base name is passed in, and the return value is the base name, or the base name extended with a suffix to make it unique.

This class is not threadsafe.

Constructor:
public IdAllocator() { this(""); } Creates a new allocator with no namespace.
public IdAllocator(String namespace) { this(namespace, new HashMap< String, NameGenerator >()); } Creates a new allocator with the provided namespace.

Method from org.apache.tapestry5.ioc.internal.util.IdAllocator Summary:
allocateId,   clear,   clone,   getAllocatedIds,   isAllocated

Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait

Method from org.apache.tapestry5.ioc.internal.util.IdAllocator Detail:
public String allocateId(String name) { String key = name + namespace; NameGenerator g = generatorMap.get(key); String result; if (g == null) { g = new NameGenerator(key); result = key; } else result = g.nextId(); // Handle the degenerate case, where a base name of the form "foo_0" has been // requested. Skip over any duplicates thus formed. while (generatorMap.containsKey(result)) result = g.nextId(); generatorMap.put(result, g); return result; } Allocates the id. Repeated calls for the same name will return "name", "name_0", "name_1", etc.
public void clear() { generatorMap.clear(); } Clears the allocator, resetting it to freshly allocated state.
public IdAllocator clone() { // Copying the generatorMap is tricky; multiple keys will point to the same NameGenerator // instance. We need to clone the NameGenerators, then build a new map around the clones. IdentityHashMap< NameGenerator, NameGenerator > transformMap = new IdentityHashMap< NameGenerator, NameGenerator >(); for (NameGenerator original : generatorMap.values()) { NameGenerator copy = original.clone(); transformMap.put(original, copy); } Map< String, NameGenerator > mapCopy = CollectionFactory.newMap(); for (String key : generatorMap.keySet()) { NameGenerator original = generatorMap.get(key); NameGenerator copy = transformMap.get(original); mapCopy.put(key, copy); } return new IdAllocator(namespace, mapCopy); } Creates a clone of this IdAllocator instance, copying the allocator's namespace and key map.
public List<String> getAllocatedIds() { return InternalUtils.sortedKeys(generatorMap); } Returns a list of all allocated ids, sorted alphabetically.
public boolean isAllocated(String name) { return generatorMap.containsKey(name); } Checks to see if a given name has been allocated.