com.allanbank.mongodb.bson.io

Class StringDecoderCache.TrieCache

java.lang.Object

com.allanbank.mongodb.bson.io.StringDecoderCache.TrieCache

Enclosing class:

StringDecoderCache

protected static class StringDecoderCache.TrieCache
extends Object

A fast cache for bytes to decoded strings.

The trie is designed to be used in a RCU fashion where the trie is constructed as a series of addEntry(byte[], String) calls and once the trie is fully populated then is can be queried using find(byte[], int, int).

API Warning:

This class is NOT part of the drivers API. This class may be mutated in incompatible ways between any two releases of the driver.

Copyright ©:

2014, Allanbank Consulting, Inc., All Rights Reserved

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	StringDecoderCache.TrieCache.TrieNode Node provides a single node in the trie.

Constructor Summary

Constructors

Constructor and Description
StringDecoderCache.TrieCache() Creates a new TrieCache.

Method Summary

Methods

Modifier and Type	Method and Description
void	addEntry(byte[] source, String value) Adds an entry to the trie cache.
String	find(byte[] source, int offset, int length) Finds the value for the byte string, if known to the cache.

Methods inherited from class java.lang.Object

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

Constructor Detail

StringDecoderCache.TrieCache

public StringDecoderCache.TrieCache()

Creates a new TrieCache.

Method Detail

addEntry

public void addEntry(byte[] source,
            String value)

Adds an entry to the trie cache.

Parameters:

source - The source of the bytes in the string.

value - The value to associate with the entry.

find

public String find(byte[] source,
          int offset,
          int length)

Finds the value for the byte string, if known to the cache. Returns null on a cache miss.

Parameters:

source - The source of the bytes in the string.

offset - The offset of the first byte to decode.

length - The length of the string to decode with a terminal zero byte.

Returns:

The cached decoded string or null in the case of a cache miss.