Package freemarker.template

Interface ObjectWrapper

All Known Subinterfaces:

ObjectWrapperAndUnwrapper, ObjectWrapperWithAPISupport, RichObjectWrapper

All Known Implementing Classes:

BeansWrapper, DefaultObjectWrapper, JythonWrapper, RhinoWrapper, SimpleObjectWrapper

public interface ObjectWrapper

Maps Java objects to the type-system of FreeMarker Template Language (see the TemplateModel interfaces). Thus this is what decides what parts of the Java objects will be accessible in the templates and how.

For example, with a BeansWrapper both the items of Map and the JavaBean properties (the getters) of an object are accessible in template uniformly with the myObject.foo syntax, where "foo" is the map key or the property name. This is because both kind of object is wrapped by BeansWrapper into a TemplateHashModel implementation that will call Map.get(Object) or the getter method, transparently to the template language.

See Also:

Configuration.setObjectWrapper(ObjectWrapper)

Field Summary

Fields

Modifier and Type	Field	Description
static ObjectWrapper	BEANS_WRAPPER	Deprecated. Use BeansWrapperBuilder.build() instead; this instance isn't read-only and thus can't be trusted.
static ObjectWrapper	DEFAULT_WRAPPER	Deprecated. Use DefaultObjectWrapperBuilder.build() instead; this instance isn't read-only and thus can't be trusted.
static ObjectWrapper	SIMPLE_WRAPPER	Deprecated. No replacement as it was seldom if ever used by anyone; this instance isn't read-only and thus can't be trusted.

Method Summary

Modifier and Type	Method	Description
TemplateModel	wrap(Object obj)	Makes a TemplateModel out of a non-TemplateModel object, usually by "wrapping" it into a TemplateModel implementation that delegates to the original object.

Field Details

BEANS_WRAPPER

@Deprecated
static final ObjectWrapper BEANS_WRAPPER

Deprecated.

Use BeansWrapperBuilder.build() instead; this instance isn't read-only and thus can't be trusted.

An ObjectWrapper that exposes the object methods and JavaBeans properties as hash elements, and has custom handling for Java Map-s, ResourceBundle-s, etc. It doesn't treat Node-s and Jython objects specially, however. As of 2.3.22, using DefaultObjectWrapper with its incompatibleImprovements property set to 2.3.22 (or higher) is recommended instead.

DEFAULT_WRAPPER

@Deprecated
static final ObjectWrapper DEFAULT_WRAPPER

Deprecated.

Use DefaultObjectWrapperBuilder.build() instead; this instance isn't read-only and thus can't be trusted.

The legacy default object wrapper implementation, focusing on backward compatibility and out-of-the W3C DOM wrapping box extra features. See DefaultObjectWrapper for more information.

SIMPLE_WRAPPER

@Deprecated
static final ObjectWrapper SIMPLE_WRAPPER

Deprecated.

No replacement as it was seldom if ever used by anyone; this instance isn't read-only and thus can't be trusted.

Object wrapper that uses SimpleXXX wrappers only. It behaves like the DEFAULT_WRAPPER, but for objects that it does not know how to wrap as a SimpleXXX it throws an exception. It makes no use of reflection-based exposure of anything, which may makes it a good candidate for security-restricted applications.

Method Details

wrap

TemplateModel wrap(Object obj)
            throws TemplateModelException

Makes a TemplateModel out of a non-TemplateModel object, usually by "wrapping" it into a TemplateModel implementation that delegates to the original object.

Parameters:

obj - The object to wrap into a TemplateModel. If it already implements TemplateModel, it should just return the object as is. If it's null, the method should return null (however, BeansWrapper, has a legacy option for returning a null model object instead, but it's not a good idea).

Returns:

a TemplateModel wrapper of the object passed in. To support un-wrapping, you may consider the return value to implement WrapperTemplateModel and AdapterTemplateModel. The default expectation is that the TemplateModel isn't less thread safe than the wrapped object. If the ObjectWrapper returns less thread safe objects, that should be clearly documented, as it restricts how it can be used, like, then it can't be used to wrap "shared variables" (Configuration.setSharedVaribles(Map)).

Throws:

TemplateModelException