Package freemarker.template

Class DefaultMapAdapter

java.lang.Object

freemarker.template.WrappingTemplateModel

freemarker.template.DefaultMapAdapter

All Implemented Interfaces:

WrapperTemplateModel, AdapterTemplateModel, TemplateHashModel, TemplateHashModelEx, TemplateHashModelEx2, TemplateModel, TemplateModelWithAPISupport, Serializable

public class DefaultMapAdapter
extends WrappingTemplateModel
implements TemplateHashModelEx2, AdapterTemplateModel, WrapperTemplateModel, TemplateModelWithAPISupport, Serializable

Adapts a Map to the corresponding TemplateModel interface(s), most importantly to TemplateHashModelEx. If you aren't wrapping an already existing Map, but build a hash specifically to be used from a template, also consider using SimpleHash (see comparison there).

Thread safety: A DefaultMapAdapter is as thread-safe as the Map that it wraps is. Normally you only have to consider read-only access, as the FreeMarker template language doesn't allow writing these hashes (though of course, Java methods called from the template can violate this rule).

This adapter is used by DefaultObjectWrapper if its useAdaptersForCollections property is true, which is the default when its incompatibleImprovements property is 2.3.22 or higher.

Since:

2.3.22

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface freemarker.template.TemplateHashModelEx2

TemplateHashModelEx2.KeyValuePair, TemplateHashModelEx2.KeyValuePairIterator

Field Summary

Fields inherited from interface freemarker.template.TemplateModel

NOTHING

Method Summary

Modifier and Type	Method	Description
static DefaultMapAdapter	adapt(Map map, ObjectWrapperWithAPISupport wrapper)	Factory method for creating new adapter instances.
TemplateModel	get(String key)	Gets a TemplateModel from the hash.
Object	getAdaptedObject(Class hint)	Retrieves the underlying object, or some other object semantically equivalent to its value narrowed by the class hint.
TemplateModel	getAPI()	Returns the model that exposes the (Java) API of the value.
Object	getWrappedObject()	Retrieves the original object wrapped by this model.
boolean	isEmpty()
TemplateCollectionModel	keys()
TemplateHashModelEx2.KeyValuePairIterator	keyValuePairIterator()
int	size()
TemplateCollectionModel	values()

Methods inherited from class freemarker.template.WrappingTemplateModel

getDefaultObjectWrapper, getObjectWrapper, setDefaultObjectWrapper, setObjectWrapper, wrap

Methods inherited from class java.lang.Object

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

Method Details

adapt

public static DefaultMapAdapter adapt(Map map,
 ObjectWrapperWithAPISupport wrapper)

Factory method for creating new adapter instances.

Parameters:

map - The map to adapt; can't be null.

wrapper - The ObjectWrapper used to wrap the items in the array.

get

public TemplateModel get(String key)
                  throws TemplateModelException

Description copied from interface: TemplateHashModel

Gets a TemplateModel from the hash.

Specified by:

get in interface TemplateHashModel

Parameters:

key - The name by which the TemplateModel is identified in the template.

Returns:

The TemplateModel referred to by the key, or null if not found.

Throws:

TemplateModelException

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface TemplateHashModel

size

public int size()

Specified by:

size in interface TemplateHashModelEx

Returns:

the number of key/value mappings in the hash.

keys

public TemplateCollectionModel keys()

Specified by:

keys in interface TemplateHashModelEx

Returns:

a collection containing the keys in the hash. Every element of the returned collection must implement the TemplateScalarModel (as the keys of hashes are always strings).

values

public TemplateCollectionModel values()

Specified by:

values in interface TemplateHashModelEx

Returns:

a collection containing the values in the hash. The elements of the returned collection can be any kind of TemplateModel-s.

keyValuePairIterator

public TemplateHashModelEx2.KeyValuePairIterator keyValuePairIterator()

Specified by:

keyValuePairIterator in interface TemplateHashModelEx2

Returns:

The iterator that walks through the key-value pairs in the hash. Not null.

getAdaptedObject

public Object getAdaptedObject(Class hint)

Description copied from interface: AdapterTemplateModel

Retrieves the underlying object, or some other object semantically equivalent to its value narrowed by the class hint.

Specified by:

getAdaptedObject in interface AdapterTemplateModel

Parameters:

hint - the desired class of the returned value. An implementation should make reasonable effort to retrieve an object of the requested class, but if that is impossible, it must at least return the underlying object as-is. As a minimal requirement, an implementation must always return the exact underlying object when hint.isInstance(underlyingObject) holds. When called with java.lang.Object.class, it should return a generic Java object (i.e. if the model is wrapping a scripting language object that is further wrapping a Java object, the deepest underlying Java object should be returned).

Returns:

the underlying object, or its value accommodated for the hint class.

getWrappedObject

public Object getWrappedObject()

Description copied from interface: WrapperTemplateModel

Retrieves the original object wrapped by this model.

Specified by:

getWrappedObject in interface WrapperTemplateModel

getAPI

public TemplateModel getAPI()
                     throws TemplateModelException

Description copied from interface: TemplateModelWithAPISupport

Returns the model that exposes the (Java) API of the value. This is usually implemented by delegating to ObjectWrapperWithAPISupport.wrapAsAPI(Object).

Specified by:

getAPI in interface TemplateModelWithAPISupport

Throws:

TemplateModelException