/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.jena.graph.impl;
import org.apache.jena.graph.* ;
import org.apache.jena.shared.* ;
/**
This base class provides convenience functions for the three "usual" graph
makers and a place to hold the reification style for the graphs it constructs.
*/
public abstract class BaseGraphMaker implements GraphMaker
{
/**
Construct the base level of a graph maker.
*/
public BaseGraphMaker( ) { }
private int counter = 0;
/**
Answer the default graph for this maker. If we haven't already made it, make it
now.
*/
@Override
public Graph getGraph()
{
if (defaultGraph == null) { defaultGraph = createGraph(); }
return defaultGraph;
}
private Graph defaultGraph;
@Override
public Graph openGraph()
{ if (defaultGraph == null) throw new DoesNotExistException
( "no default graph in this GraphMaker [" + this.getClass() + "]" );
return defaultGraph; }
/**
Make a fresh anonymous graph.
*/
@Override
public Graph createGraph()
{ return createGraph( "anon_" + counter++ + "", false ); }
/**
A non-strict create.
@see org.apache.jena.graph.GraphMaker#createGraph(java.lang.String)
*/
@Override
public Graph createGraph(String name)
{ return createGraph( name, false ); }
/**
A non-strict open.
@see org.apache.jena.graph.GraphMaker#openGraph(java.lang.String)
*/
@Override
public Graph openGraph( String name )
{ return openGraph( name, false ); }
}