/*

  * 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.any23.writer;

 import org.apache.any23.extractor.ExtractionContext;

 import org.openrdf.model.Resource;

 import org.openrdf.model.URI;

 import org.openrdf.model.Value;

 import java.io.OutputStream;

 import java.io.PrintStream;

 import java.util.ArrayList;

 import java.util.List;

 /**

  * This writer simply produces a list of unique <i>URI</i> present in the

  * subject or in the object of every single extracted <i>RDF Statement</i>.

  * 

  * @author Davide Palmisano (palmisano@fbk.eu)

  */

 @Writer(identifier = "uri", mimeType = "text/plain")

 public class URIListWriter implements FormatWriter {

     private List<Resource> resources;

     private PrintStream printStream;

     private ExtractionContext extractionContext;

     private long contentLength;

     public URIListWriter(OutputStream outputStream) {

         this.resources = new ArrayList<Resource>();

         this.printStream = new PrintStream(outputStream);

     }

     public void startDocument(URI documentURI) throws TripleHandlerException {}

     public void openContext(ExtractionContext context) throws TripleHandlerException {

         this.extractionContext = context;

     }

     public void receiveTriple(Resource s, URI p, Value o, URI g, ExtractionContext context)

             throws TripleHandlerException {

         if(!this.resources.contains(s)) {

             this.resources.add(s);

             this.printStream.println(s.stringValue());

         }

         if(o instanceof Resource && !this.resources.contains(o)) {

             this.resources.add((Resource) o);

             this.printStream.println(o.stringValue());

         }

     }

     public void receiveNamespace(String prefix, String uri, ExtractionContext context)

             throws TripleHandlerException {

     }

     public void closeContext(ExtractionContext context) throws TripleHandlerException {

     }

     public void endDocument(URI documentURI) throws TripleHandlerException {

     }

     public void setContentLength(long contentLength) {

         this.contentLength = contentLength;

     }

     public void close() throws TripleHandlerException {

         this.printStream.close();

     }

     @Override

     public boolean isAnnotated() {

         return false;

     }

     @Override

     public void setAnnotated(boolean f) {

         // Empty.

     }

 }