/*
* Copyright 2012-2013 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
*
* 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 org.springframework.hateoas.core;
import org.springframework.hateoas.EntityLinks;
import org.springframework.hateoas.Link;
import org.springframework.hateoas.LinkBuilder;
import org.springframework.plugin.core.PluginRegistry;
import org.springframework.util.Assert;
/**
* {@link EntityLinks} implementation that delegates to the {@link EntityLinks} instances registered in the
* {@link PluginRegistry} given on instance creation.
*
* @author Oliver Gierke
*/
public class DelegatingEntityLinks extends AbstractEntityLinks {
private final PluginRegistry<EntityLinks, Class<?>> delegates;
/**
* Creates a new {@link DelegatingEntityLinks} using the given {@link PluginRegistry}.
*
* @param plugins must not be {@literal null}.
*/
public DelegatingEntityLinks(PluginRegistry<EntityLinks, Class<?>> plugins) {
Assert.notNull(plugins, "PluginRegistry must not be null!");
this.delegates = plugins;
}
/*
* (non-Javadoc)
* @see org.springframework.hateoas.EntityLinks#linkFor(java.lang.Class)
*/
@Override
public LinkBuilder linkFor(Class<?> type) {
return getPluginFor(type).linkFor(type);
}
/*
* (non-Javadoc)
* @see org.springframework.hateoas.EntityLinks#linkFor(java.lang.Class, java.lang.Object[])
*/
@Override
public LinkBuilder linkFor(Class<?> type, Object... parameters) {
return getPluginFor(type).linkFor(type, parameters);
}
/*
* (non-Javadoc)
* @see org.springframework.hateoas.EntityLinks#getLinkToCollectionResource(java.lang.Class)
*/
@Override
public Link linkToCollectionResource(Class<?> type) {
return getPluginFor(type).linkToCollectionResource(type);
}
/*
* (non-Javadoc)
* @see org.springframework.hateoas.EntityLinks#getLinkToSingleResource(java.lang.Class, java.lang.Object)
*/
@Override
public Link linkToSingleResource(Class<?> type, Object id) {
return getPluginFor(type).linkToSingleResource(type, id);
}
/*
* (non-Javadoc)
* @see org.springframework.plugin.core.Plugin#supports(java.lang.Object)
*/
@Override
public boolean supports(Class<?> delimiter) {
return delegates.hasPluginFor(delimiter);
}
/**
* Returns the plugin for the given type or throws an {@link IllegalArgumentException} if no delegate
* {@link EntityLinks} can be found.
*
* @param type must not be {@literal null}.
* @return
*/
private EntityLinks getPluginFor(Class<?> type) {
EntityLinks plugin = delegates.getPluginFor(type);
if (plugin == null) {
throw new IllegalArgumentException(String.format(
"Cannot determine link for %s! No EntityLinks instance found supporting the domain type!", type.getName()));
}
return plugin;
}
}