freemarker.template.TemplateHashModelEx Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package freemarker.template;
/**
* "extended hash" template language data type; extends {@link TemplateHashModel} by allowing
* iterating through its keys and values. Consider implementing the modern variation of this,
* {@link TemplateHashModelEx2}, which allows the more efficient listing of key-value pairs.
*
* In templates they are used like hashes, but these will also work (among others):
* {@code myExtHash?size}, {@code myExtHash?keys}, {@code myExtHash?values}, {@code <#list myMap as k, v>}.
*
* @see DefaultMapAdapter
* @see SimpleHash
*/
public interface TemplateHashModelEx extends TemplateHashModel {
/**
* @return the number of key/value mappings in the hash.
*/
int size() throws TemplateModelException;
/**
* @return a collection containing the keys in the hash. Every element of
* the returned collection must implement the {@link TemplateScalarModel}
* (as the keys of hashes are always strings).
*/
TemplateCollectionModel keys() throws TemplateModelException;
/**
* @return a collection containing the values in the hash. The elements of the
* returned collection can be any kind of {@link TemplateModel}-s.
*/
TemplateCollectionModel values() throws TemplateModelException;
}