com.emc.atmos.api.request.ListRequest Maven / Gradle / Ivy
/*
* Copyright 2013 EMC Corporation. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://www.apache.org/licenses/LICENSE-2.0.txt
*
* or in the "license" file accompanying this file. This file 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.emc.atmos.api.request;
import com.emc.atmos.api.RestUtil;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
/**
* Common elements of a request for a list of items. Atmos uses the limit and token headers to page results. The limit
* is specified in the request to limit the number of results returned. The token is specified in the response to
* signify that there are more results to get and in the request to get the next page of results.
*
* @param Represents the implementation type. Allows a consistent builder interface throughout the request
* hierarchy. Parameterize concrete subclasses with their own type and implement {@link #me()} to return
* "this". In abstract subclasses, return me() in builder methods.
*/
public abstract class ListRequest> extends Request {
protected int limit;
protected String token;
/**
* Returns "this" in concrete implementation classes. Used in builder methods to be consistent throughout the
* hierarchy. For example, you can call new CreateObjectRequest().identifier(path).content(content).
*
* @return this
*/
protected abstract T me();
@Override
public Map> generateHeaders() {
Map> headers = new TreeMap>();
RestUtil.addValue( headers, RestUtil.XHEADER_UTF8, "true" );
if ( limit > 0 ) RestUtil.addValue( headers, RestUtil.XHEADER_LIMIT, limit );
if ( token != null ) RestUtil.addValue( headers, RestUtil.XHEADER_TOKEN, token );
return headers;
}
/**
* Builder method for {@link #setLimit(int)}
*/
public T limit( int limit ) {
setLimit( limit );
return me();
}
/**
* Builder method for {@link #setToken(String)}
*/
public T token( String token ) {
setToken( token );
return me();
}
/**
* Gets the limit (page size) for this request.
*/
public int getLimit() {
return limit;
}
/**
* Gets the cursor token for this request, returned in the response to indicate there is another page of results
* and in the request to get the next page of results.
*/
public String getToken() {
return token;
}
/**
* Sets the limit (page size) for this request.
*/
public void setLimit( int limit ) {
this.limit = limit;
}
/**
* Sets the cursor token for this request, returned in the response to indicate there is another page of results
* and in the request to get the next page of results. API implementations should set this value automatically if
* it is returned in the response, so you can check this value for null to see if you have received the entire
* list.
*/
public void setToken( String token ) {
this.token = token;
}
}