org.springframework.ui.Model Maven / Gradle / Ivy
/*
* Copyright 2002-2022 the original author or authors.
*
* Licensed 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
*
* https://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 org.springframework.ui;
import java.util.Collection;
import java.util.Map;
import org.springframework.lang.Nullable;
/**
* Interface that defines a holder for model attributes.
*
* Primarily designed for adding attributes to the model.
*
*
Allows for accessing the overall model as a {@code java.util.Map}.
*
* @author Juergen Hoeller
* @since 2.5.1
*/
public interface Model {
/**
* Add the supplied attribute under the supplied name.
* @param attributeName the name of the model attribute (never {@code null})
* @param attributeValue the model attribute value (can be {@code null})
*/
Model addAttribute(String attributeName, @Nullable Object attributeValue);
/**
* Add the supplied attribute to this {@code Map} using a
* {@link org.springframework.core.Conventions#getVariableName generated name}.
*
Note: Empty {@link java.util.Collection Collections} are not added to
* the model when using this method because we cannot correctly determine
* the true convention name. View code should check for {@code null} rather
* than for empty collections as is already done by JSTL tags.
* @param attributeValue the model attribute value (never {@code null})
*/
Model addAttribute(Object attributeValue);
/**
* Copy all attributes in the supplied {@code Collection} into this
* {@code Map}, using attribute name generation for each element.
* @see #addAttribute(Object)
*/
Model addAllAttributes(Collection attributeValues);
/**
* Copy all attributes in the supplied {@code Map} into this {@code Map}.
* @see #addAttribute(String, Object)
*/
Model addAllAttributes(Map attributes);
/**
* Copy all attributes in the supplied {@code Map} into this {@code Map},
* with existing objects of the same name taking precedence (i.e. not getting
* replaced).
*/
Model mergeAttributes(Map attributes);
/**
* Does this model contain an attribute of the given name?
* @param attributeName the name of the model attribute (never {@code null})
* @return whether this model contains a corresponding attribute
*/
boolean containsAttribute(String attributeName);
/**
* Return the attribute value for the given name, if any.
* @param attributeName the name of the model attribute (never {@code null})
* @return the corresponding attribute value, or {@code null} if none
* @since 5.2
*/
@Nullable
Object getAttribute(String attributeName);
/**
* Return the current set of model attributes as a Map.
*/
Map asMap();
}