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Java client API for Franz AllegroGraph

There is a newer version: 5.0.2

package com.franz.agraph.repository;

import org.json.JSONObject;

/**
 * A nestable class for defining a scope over which user attributes are set
 * on an AGRepositoryConnection.
 * 
 * A UserAttributeContext can be used with a try-with-resources statement to automate
 * the saving, setting and restoring of userAttributes on an AGRepositoryConnection
 * object. It is intended as an aid to help ensure a specific set of user attributes
 * are not leaked outside the scope of their intended use.
 * 
 * Any request made between instantiation of this class and a call to the close()
 * method will automatically have an x-user-attributes header added to each request
 * sent to via the AGRepositoryConnection object passed as an argument to one of
 * the constructors. While the context instance is live, and before close() is called,
 * the AGRepositoryConnection can be use directly, or referenced via the `conn' field
 * of the context itself.
 * 
 * See example25() for sample code demonstrating its use.
 *
 */
public class UserAttributesContext implements AutoCloseable {
	public AGRepositoryConnection conn;
	private String oldUserAttrs;
	
	/**
	 * Instantiate a UserAttributesContext object. Saves any existing userAttributes
	 * set on the argument connection object via connection.getUserAttributes() and then
	 * calls connection.setUserAttributes(attrs).
	 * 
	 * @param connection, an instance of AGRepositoryConnection
	 * @param attrs, a String representing a JSON object comprising a collection of
	 * 		attribute/value pairs.
	 */
	public UserAttributesContext(AGRepositoryConnection connection, String attrs) {
		conn = connection;
		oldUserAttrs = conn.getUserAttributes();
		conn.setUserAttributes(attrs);
	}
	
	/**
	 * Instantiate a UserAttributesContext object. Saves any existing userAttributes
	 * set on the argument connection object via connection.getUserAttributes() and then
	 * calls connection.setUserAttributes(attrs).
	 * 
	 * @param connection, an instance of AGRepositoryConnection
	 * @param attrs, a JSONObject comprising a collection of attribute/value pairs.
	 *
	 */
	public UserAttributesContext(AGRepositoryConnection connection, JSONObject attrs) {
		conn = connection;
		oldUserAttrs = conn.getUserAttributes();
		conn.setUserAttributes(attrs);
	}
	
	/**
	 * restore, via conn.setUserAttributes() the user attributes that were defined on 
	 * the AGRepositoryConnection object passed to the constructor of this instance.
	 */
	public void close() {
		conn.setUserAttributes(oldUserAttrs);
	}
}