freemarker.ext.misc
Class CollectionSize

java.lang.Object
  freemarker.ext.misc.CollectionSize

All Implemented Interfaces:

TemplateMethodModel2, TemplateModel, java.io.Serializable

public final class CollectionSize
extends java.lang.Object
implements TemplateMethodModel2, java.io.Serializable

Determines the size of the underlying Collection or Map object given a TemplateObjectModel. Does this by calling the getAsObject method. If the object is of the expected type, the size is returned as a FastNumber. Otherwise, a TemplateModelException is thrown.

Usage:
From java:

 TemplateModelRoot root = new SimpleHash();

 root.put( "size", freemarker.ext.misc.CollectionSize.getInstance() );

 ...
 

From your FM-Classic template:

 <assign list1 = [ "test1", "test2", "test3" ]>
 <assign listSize = size( list1 )>
 <p>The size of list1 is: ${listSize}</p>

 ...
 

Note:
CollectionSize is a singleton instance. Use the getInstance() method to retrieve instances of this model.

Since:

1.8

Version:

$Id: CollectionSize.java 1101 2013-04-01 04:17:32Z run2000 $

Author:

Nicholas Cull

See Also:

Serialized Form

Method Summary

TemplateModel	exec(java.util.List<TemplateModel> arguments) Retrieves the size of the given Collection or Map.
static CollectionSize	getInstance() Retrieve a singleton instance of this class.
boolean	isEmpty() Is the object empty?

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static CollectionSize getInstance()

Retrieve a singleton instance of this class. Since there is no state information held between calls, there is only a need for one instance.

Returns:

an instance of this CollectionSize class

isEmpty

public boolean isEmpty()
                throws TemplateModelException

Is the object empty?

Specified by:

isEmpty in interface TemplateModel

Returns:

false, since the method is never empty

Throws:

TemplateModelException

exec

public TemplateModel exec(java.util.List<TemplateModel> arguments)
                   throws TemplateModelException

Retrieves the size of the given Collection or Map. Performs an unwrapping by calling getAsObject, then calls the size method of the underlying object.

Specified by:

exec in interface TemplateMethodModel2

Parameters:

arguments - a List containing a TemplateObjectMode as its single item

Returns:

the size of the Collection or Map as a TemplateNumberModel

Throws:

TemplateModelException - the size could not be determined