com.gwtplatform.dispatch.rest.client.ActionMetadataProvider Maven / Gradle / Ivy
/**
* Copyright 2013 ArcBees Inc.
*
* 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 com.gwtplatform.dispatch.rest.client;
import com.google.common.base.Objects;
import com.gwtplatform.dispatch.rest.shared.MetadataType;
import com.gwtplatform.dispatch.rest.shared.RestAction;
/**
* An implementation of this class is generated at compile-time to provide additional information about generated
* {@link RestAction}s. Possible metadata is enumerated in {@link MetadataType}.
*/
public interface ActionMetadataProvider {
/**
* A key composed of {@link RestAction} and a {@link MetadataType}.
*/
class MetadataKey {
private final Class actionClass;
private final MetadataType metadataType;
MetadataKey(Class actionClass,
MetadataType metadataType) {
this.actionClass = actionClass;
this.metadataType = metadataType;
}
public static MetadataKey create(Class actionClass, MetadataType metadataType) {
return new MetadataKey(actionClass, metadataType);
}
@Override
public int hashCode() {
return Objects.hashCode(actionClass, metadataType);
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || !(o instanceof MetadataKey)) {
return false;
}
MetadataKey other = (MetadataKey) o;
return Objects.equal(actionClass, other.actionClass) && Objects.equal(metadataType, other.metadataType);
}
}
/**
* Retrieve metadata for the given action and {@link MetadataType} pair.
*
* @param action The action for which to retrieve metadata.
* @param metadataType The kind of metadata to retrieve.
* @return The stored value for the given parameters or null if there is no match.
*/
Object getValue(RestAction action, MetadataType metadataType);
}