com.huawei.openstack4j.openstack.common.ListResult Maven / Gradle / Ivy
/*******************************************************************************
* Copyright 2016 ContainX and OpenStack4j
*
* 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.huawei.openstack4j.openstack.common;
import java.util.Collections;
import java.util.List;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.huawei.openstack4j.core.transport.ListType;
import com.huawei.openstack4j.model.ModelEntity;
/**
* A List result which wrappers a JSON Array
*
* @param the generic type
*/
public abstract class ListResult implements ModelEntity, ListType {
private static final long serialVersionUID = 1L;
protected abstract List value();
@JsonIgnore
public List getList() {
if (value() == null)
return Collections.emptyList();
return value();
}
public T first() {
return value().isEmpty() ? null : value().get(0);
}
}