groovy.json.internal

Class LazyValueMap

java.lang.Object

java.util.AbstractMap<String,Object>

groovy.json.internal.LazyValueMap

All Implemented Interfaces:

ValueMap<String,Object>, Map<String,Object>

public class LazyValueMap
extends AbstractMap<String,Object>
implements ValueMap<String,Object>

This class is important to the performance of the parser. It stores Value objects in a map where they are evaluated lazily. This is great for JSONPath types of application, and Object Serialization but not for maps that are going to be stored in a cache.

This is because the Value construct is a type of index overlay that merely tracks where the token is located in the buffer, and what if any thing we noted about it (like can be converted to a decimal number, etc.).

To mitigate memory leaks this class along with CharSequenceValue implement two constructs, namely, chop, and lazyChop.

A chop is when we convert backing buffer of a Value object into a smaller buffer. A lazyChop is when we do a chop but only when a get operation is called.

The lazyChop is performed on the tree that is touched by the JSONPath expression or its ilk.

The chop operation can be done during parsing or lazily by storing the values in this construct.

Author:

Rick Hightower (insane chipmonk)

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Constructor Summary

Constructors

Constructor and Description
LazyValueMap(boolean lazyChop)
LazyValueMap(boolean lazyChop, int initialSize)

Method Summary

Methods

Modifier and Type	Method and Description
void	add(MapItemValue miv) Adds a new MapItemValue to the mapping.
void	chopMap() Chop this map.
Set<Map.Entry<String,Object>>	entrySet()
Object	get(Object key) Gets the item by key from the mapping.
boolean	hydrated() Has the map been hydrated.
Map.Entry<String,Value>[]	items() Give me the items in the map without hydrating the map.
int	len() Return size w/o hydrating the map.
Value	put(String key, Object value)
int	size()
String	toString()
Collection<Object>	values()

Methods inherited from class java.util.AbstractMap

clear, clone, containsKey, containsValue, equals, hashCode, isEmpty, keySet, putAll, remove

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Map

clear, containsKey, containsValue, equals, hashCode, isEmpty, keySet, putAll, remove

Constructor Detail

LazyValueMap

public LazyValueMap(boolean lazyChop)

LazyValueMap

public LazyValueMap(boolean lazyChop,
            int initialSize)

Method Detail

add

public final void add(MapItemValue miv)

Adds a new MapItemValue to the mapping.

Specified by:

add in interface ValueMap<String,Object>

Parameters:

miv - miv we are adding.

get

public final Object get(Object key)

Gets the item by key from the mapping.

Specified by:

get in interface Map<String,Object>

Overrides:

get in class AbstractMap<String,Object>

Parameters:

key - to lookup

Returns:

the item for the given key

chopMap

public final void chopMap()

Chop this map.

put

public Value put(String key,
        Object value)

Specified by:

put in interface Map<String,Object>

Overrides:

put in class AbstractMap<String,Object>

entrySet

public Set<Map.Entry<String,Object>> entrySet()

Specified by:

entrySet in interface Map<String,Object>

Specified by:

entrySet in class AbstractMap<String,Object>

values

public Collection<Object> values()

Specified by:

values in interface Map<String,Object>

Overrides:

values in class AbstractMap<String,Object>

size

public int size()

Specified by:

size in interface Map<String,Object>

Overrides:

size in class AbstractMap<String,Object>

toString

public String toString()

Overrides:

toString in class AbstractMap<String,Object>

len

public int len()

Description copied from interface: ValueMap

Return size w/o hydrating the map.

Specified by:

len in interface ValueMap<String,Object>

hydrated

public boolean hydrated()

Description copied from interface: ValueMap

Has the map been hydrated.

Specified by:

hydrated in interface ValueMap<String,Object>

items

public Map.Entry<String,Value>[] items()

Description copied from interface: ValueMap

Give me the items in the map without hydrating the map. Realize that the array is likely larger than the length so array items can be null.

Specified by:

items in interface ValueMap<String,Object>