Package freemarker.ext.beans

Class GenericObjectModel

java.lang.Object

freemarker.ext.beans.BeanModel

freemarker.ext.beans.StringModel

freemarker.ext.beans.GenericObjectModel

All Implemented Interfaces:

WrapperTemplateModel, AdapterTemplateModel, MethodCallAwareTemplateHashModel, TemplateHashModel, TemplateHashModelEx, TemplateModel, TemplateModelWithAPISupport, TemplateScalarModel

public class GenericObjectModel
extends StringModel
implements MethodCallAwareTemplateHashModel

This is used for wrapping objects that has no special treatment (unlike Map-s, Collection-s, Number-s, Boolean-s, and some more, which have), hence they are just "generic" Java objects. Users usually just want to call the public Java methods on such objects. These objects can also be used as string values in templates, and that value is provided by the Object.toString() method of the wrapped object.

This extends StringModel for backward compatibility, as now BeansWrapper returns instances of GenericObjectModel instead of StringModel-s, but user code may have insteanceof StringModel, or casing to StringModel. StringModel served the same purpose as this class, but didn't implement MethodCallAwareTemplateHashModel.

Since:

2.3.33

Nested Class Summary

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

MethodCallAwareTemplateHashModel.ShouldNotBeGetAsMethodException

Field Summary

Fields inherited from class freemarker.ext.beans.BeanModel

object, wrapper

Fields inherited from interface freemarker.template.TemplateModel

NOTHING

Fields inherited from interface freemarker.template.TemplateScalarModel

EMPTY_STRING

Constructor Summary

Constructors

Constructor	Description
GenericObjectModel(Object object, BeansWrapper wrapper)	Creates a new model that wraps the specified object with BeanModel + scalar functionality.

Method Summary

Modifier and Type	Method	Description
TemplateModel	get(String key)	Uses Beans introspection to locate a property or method with name matching the key name.
TemplateModel	getBeforeMethodCall(String key)	Can be overridden to be public, to implement MethodCallAwareTemplateHashModel.

Methods inherited from class freemarker.ext.beans.StringModel

getAsString

Methods inherited from class freemarker.ext.beans.BeanModel

get, getAdaptedObject, getAPI, getWrappedObject, hasPlainGetMethod, invokeGenericGet, isEmpty, keys, keySet, size, toString, unwrap, values, wrap

Methods inherited from class java.lang.Object

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

Methods inherited from interface freemarker.template.TemplateHashModel

isEmpty

Constructor Details

GenericObjectModel

public GenericObjectModel(Object object,
 BeansWrapper wrapper)

Creates a new model that wraps the specified object with BeanModel + scalar functionality.

Parameters:

object - the object to wrap into a model.

wrapper - the BeansWrapper associated with this model. Every model has to have an associated BeansWrapper instance. The model gains many attributes from its wrapper, including the caching behavior, method exposure level, method-over-item shadowing policy etc.

Method Details

get

public final TemplateModel get(String key)
                        throws TemplateModelException

Description copied from class: BeanModel

Uses Beans introspection to locate a property or method with name matching the key name. If a method or property is found, it's wrapped into TemplateMethodModelEx (for a method or indexed property), or evaluated on-the-fly and the return value wrapped into appropriate model (for a non-indexed property). Models for various properties and methods are cached on a per-class basis, so the costly introspection is performed only once per property or method of a class. (Side-note: this also implies that any class whose method has been called will be strongly referred to by the framework and will not become unloadable until this class has been unloaded first. Normally this is not an issue, but can be in a rare scenario where you create many classes on- the-fly. Also, as the cache grows with new classes and methods introduced to the framework, it may appear as if it were leaking memory. The framework does, however detect class reloads (if you happen to be in an environment that does this kind of things--servlet containers do it when they reload a web application) and flushes the cache. If no method or property matching the key is found, the framework will try to invoke methods with signature non-void-return-type get(java.lang.String), then non-void-return-type get(java.lang.Object), or alternatively (if the wrapped object is a resource bundle) Object getObject(java.lang.String).

As of 2.3.33, the default implementation of this method delegates to BeanModel.get(String, boolean). It's better to override that, instead of this method. Otherwise, unwanted behavior can arise if the model class also implements MethodCallAwareTemplateHashModel, as that will certainly call BeanModel.get(String, boolean) internally, and not the overridden version of this method.

Specified by:

get in interface TemplateHashModel

Overrides:

get in class BeanModel

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 - if there was no property nor method nor a generic get method to invoke.

getBeforeMethodCall

public TemplateModel getBeforeMethodCall(String key)
                                  throws TemplateModelException,
MethodCallAwareTemplateHashModel.ShouldNotBeGetAsMethodException

Description copied from class: BeanModel

Can be overridden to be public, to implement MethodCallAwareTemplateHashModel. We don't implement that in BeanModel for backward compatibility, but the functionality is present. If you expose this method by implementing MethodCallAwareTemplateHashModel, then be sure that BeanModel.get(String) is not overridden in custom subclasses; if it is, then those subclasses should be modernized to override BeanModel.get(String, boolean) instead.

Specified by:

getBeforeMethodCall in interface MethodCallAwareTemplateHashModel

Overrides:

getBeforeMethodCall in class BeanModel

Parameters:

key - Same as for TemplateHashModel.get(String)

Returns:

Same as for TemplateHashModel.get(String), except it should return a TemplateMethodModel (a TemplateMethodModelEx if possible), or in very rare case a Macro that was created with the function directive. Or, null in the same case as TemplateHashModel.get(String). The method should never return something that's not callable in the template language as a method or function; the return type is TemplateModel because that's the most specific common super-interface of TemplateMethodModel, and Macro.

Throws:

MethodCallAwareTemplateHashModel.ShouldNotBeGetAsMethodException - If the value for the given key exists, but shouldn't be coerced to something callable as a method. This will be converted to NonMethodException by the engine, but in this exception you can optionally give a more specific explanation, and that will be added to the resulting NonMethodException as a hint to the user.

TemplateModelException