/*
* 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 java.util.*;
import org.apache.jena.graph.* ;
import org.apache.jena.mem.* ;
import org.apache.jena.shared.* ;
import org.apache.jena.util.iterator.* ;
/**
A SimpleGraphFactory produces memory-based graphs and records them
in a local map.
*/
public class SimpleGraphMaker extends BaseGraphMaker
{
/**
Initialise a SimpleGraphMaker with reification style Minimal
*/
public SimpleGraphMaker()
{ super() ; }
/**
The mapping from the names of graphs to the Graphs themselves.
*/
private Map<String, Graph> graphs = new HashMap<>();
public Graph create()
{ return Factory.createGraphMem(); }
/**
Create a graph and record it with the given name in the local map.
*/
@Override
public Graph createGraph( String name, boolean strict )
{
GraphMemBase already = (GraphMemBase) graphs.get( name );
if (already == null)
{
Graph result = Factory.createGraphMem( );
graphs.put( name, result );
return result;
}
else if (strict)
throw new AlreadyExistsException( name );
else
return already.openAgain();
}
/**
Open (aka find) a graph with the given name in the local map.
*/
@Override
public Graph openGraph( String name, boolean strict )
{
GraphMemBase already = (GraphMemBase) graphs.get( name );
if (already == null)
if (strict) throw new DoesNotExistException( name );
else return createGraph( name, true );
else
return already.openAgain();
}
@Override
public Graph openGraph()
{ return getGraph(); }
/**
Remove the mapping from name to any graph from the local map.
*/
@Override
public void removeGraph( String name )
{
if (!graphs.containsKey( name )) throw new DoesNotExistException( name );
graphs.remove( name );
}
/**
Return true iff we have a graph with the given name
*/
@Override
public boolean hasGraph( String name )
{ return graphs.containsKey( name ); }
/**
Close this factory - we choose to do nothing.
*/
@Override
public void close()
{ /* nothing to do */ }
@Override
public ExtendedIterator<String> listGraphs()
{ return WrappedIterator.create( graphs.keySet().iterator() ); }
}