org.opendaylight.yangtools.yang.data.util

Class LeafInterner

java.lang.Object

org.opendaylight.yangtools.yang.data.util.LeafInterner

@Beta
public abstract class LeafInterner
extends Object

Utility class for sharing instances of LeafNodes which have low cardinality-- e.g. those which hold boolean or enumeration values. Instances containing attributes are not interned. Such objects have cardinality which is capped at the product of QNAMES * TYPE_CARDINALITY, where QNAMES is the total number of different QNames where the type is used and TYPE_CARDINALITY is the number of possible values for the type. Boolean has cardinality of 2, enumerations have cardinality equal to the number of enum statements. The theory here is that we tend to have a large number (100K+) of entries in a few places, which could end up hogging the heap retained via the DataTree with duplicate objects (same QName, same value, different object). Using this utility, such objects will end up reusing the same object, preventing this overhead.

Method Summary

Methods

Modifier and Type	Method and Description
static LeafInterner	forSchema(LeafSchemaNode schema) Return a LeafInterner for a particular schema.
abstract <T extends LeafNode<?>> T	intern(T sample)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

forSchema

@Nonnull
public static LeafInterner forSchema(@Nullable
                             LeafSchemaNode schema)

Return a LeafInterner for a particular schema. Interner instances must not be reused for leaves of different types, otherwise they may produce unexpected results.

Parameters:

schema - The leaf node's schema

Returns:

An interner instance

intern

public abstract <T extends LeafNode<?>> T intern(T sample)