Java Code Examples for org.neo4j.driver.v1.Session#close()

@Test
public void standAloneDriver() {
    Driver driver = GraphDatabase.driver("bolt://localhost:7687", AuthTokens.basic("neo4j", "12345"));
    Session session = driver.session();

    session.run("CREATE (baeldung:Company {name:\"Baeldung\"}) " +
            "-[:owns]-> (tesla:Car {make: 'tesla', model: 'modelX'})" +
            "RETURN baeldung, tesla");

    StatementResult result = session.run("MATCH (company:Company)-[:owns]-> (car:Car)" +
            "WHERE car.make='tesla' and car.model='modelX'" +
            "RETURN company.name");

    Assert.assertTrue(result.hasNext());
    Assert.assertEquals(result.next().get("company.name").asString(), "Baeldung");

    session.close();
    driver.close();
}
 

public List<NeoProperty> getSampleProperties(NeoProfiler parent, Entity n) {
	List<NeoProperty> props = new ArrayList<NeoProperty>();
	
	Session s = parent.getDriver().session();
	try ( Transaction tx = s.beginTransaction() ) {			 
		Iterator<String> propKeys = n.keys().iterator();
		
		while(propKeys.hasNext()) {
			String key = propKeys.next();
			Object val = n.get(key);
			
			props.add(new NeoProperty(key, val.getClass().getSimpleName()));				
		}
		
	} finally {
		s.close();
	}

	return props;
}
 

public static SubGraph run(SubGraph searchResult1, ApiLocatorContext context){
    SubGraph r = new SubGraph();
    r.getNodes().addAll(searchResult1.getNodes());
    r.cost = searchResult1.cost;
    for (long node : searchResult1.getNodes()) {
        Session session = context.connection.session();
        String stat = "match p=(n1)-[:" + CodeInDocxFileExtractor.API_EXPLAINED_BY + "]->(n2) where id(n1)=" + node + " unwind relationships(p) as r return id(r), id(startNode(r)), id(endNode(r))";
        StatementResult rs = session.run(stat);
        while (rs.hasNext()) {
            Record item=rs.next();
            long node1 = item.get("id(startNode(r))").asLong();
            long node2 = item.get("id(endNode(r))").asLong();
            long rel = item.get("id(r)").asLong();
            r.getNodes().add(node1);
            r.getNodes().add(node2);
            r.getEdges().add(rel);
        }
        session.close();
    }
    return r;
}
 

public static SubGraph run(String query, SubGraph searchResult1, SubGraph linkedSearchResult1,  ApiLocatorContext context){
    SubGraph r = new SubGraph();
    r.getNodes().addAll(searchResult1.getNodes());
    r.cost = searchResult1.cost;
    List<LuceneSearchResult> luceneSearchResults=context.getLuceneSearcher().query(query);
    luceneSearchResults.sort((LuceneSearchResult a, LuceneSearchResult b)->{
        Double aDist=new Double(dist(a.nodeSet,searchResult1.getNodes(),context));
        Double bDist=new Double(dist(b.nodeSet,searchResult1.getNodes(),context));
        return aDist.compareTo(bDist);
    });
    for (int i=0;i<3&&i<luceneSearchResults.size();i++) {
        r.getNodes().add(luceneSearchResults.get(i).id);
        for (long node:linkedSearchResult1.getNodes()){
            Session session=context.connection.session();
            StatementResult rs=session.run("match (a)-[r]-(b) where id(a)="+node+" and id(b)="+luceneSearchResults.get(i).id+" return id(r)");
            while (rs.hasNext()){
                Record item=rs.next();
                r.getEdges().add(item.get("id(r)").asLong());
            }
            session.close();
        }
    }
    return r;
}
 

@Override
public void write(StreamsDatum entry) {

  List<Pair<String, Map<String, Object>>> statements;
  Session session = null;
  try {
    statements = Neo4jPersistUtil.prepareStatements(entry);
    session = client.client().session();
    Transaction transaction = session.beginTransaction();
    for( Pair<String, Map<String, Object>> statement : statements ) {
      StatementResult statementResult = transaction.run( statement.getValue0(), statement.getValue1() );
      LOGGER.debug("StatementResult", statementResult.single());
    }
    transaction.success();
  } catch( Exception ex ) {
    LOGGER.error("Exception", ex);
  } finally {
    if( session != null ) {
      session.close();
    }
  }
}
 

public String transactionEnlistmentReadAfterCallingTransactionClose() {
    // JTA transaction is started by CMT, the following obtains a Session that is enlisted into the JTA transaction.
    Session session = injectedDriver.session();
    // The only way to influence success/failure of the Neo4j + JTA transaction, is at the JTA transaction level.
    // If the JTA transaction fails, org.neo4j.driver.v1.Transaction.failure() is called.
    // If the JTA transaction succeeds, org.neo4j.driver.v1.Transaction.success() is called.
    // org.neo4j.driver.v1.Transaction.close() is also called when the JTA transaction ends.

    // Calls to Session.beginTransaction() in a JTA transaction are expected to throw a RuntimeException
    try {
        Transaction transaction = session.beginTransaction();
        fail("Calling Session.beginTransaction in a JTA transaction should throw a RuntimeException.");
    } catch (RuntimeException expectedException) {
        // success
    }

    try {
        session.run("CREATE (a:Person {name:'TRANSACTION', title:'King'})");
        return nestedBean.getPerson("TRANSACTION");
    } finally {
        if ( session.isOpen()) { // this will be true
            session.run("MATCH (a:Person) delete a");
            session.close();             // ignored, session is auto closed when the transaction ends.
        }
    }
}
 

public String addPerson() {
    Session session = driver.session();
    try {
        session.run("CREATE (a:Person {name:'Arthur', title:'King'})");
        StatementResult result = session.run("MATCH (a:Person) WHERE a.name = 'Arthur' RETURN a.name AS name, a.title AS title");


        Record record = result.next();
        return record.toString();
    } finally {
        session.run("MATCH (a:Person) delete a");
        session.close();
    }
}
 

@AfterClass
public void cleanup() throws Exception {
  Session session = testClient.client().session();
  Transaction transaction = session.beginTransaction();
  transaction.run("MATCH ()-[r]-() DELETE r");
  transaction.run("MATCH (n) DETACH DELETE n");
  transaction.success();
  session.close();
}
 

@BeforeClass
public void prepareTest() throws IOException {

  testConfiguration = new StreamsConfigurator<>(TwitterFollowNeo4jConfiguration.class).detectCustomConfiguration();
  testClient = Neo4jBoltClient.getInstance(testConfiguration.getNeo4j());

  Session session = testClient.client().session();
  Transaction transaction = session.beginTransaction();
  transaction.run("MATCH ()-[r]-() DELETE r");
  transaction.run("MATCH (n) DETACH DELETE n");
  transaction.success();
  session.close();
}
 

@AfterClass
public void cleanup() throws Exception {
  Session session = testClient.client().session();
  Transaction transaction = session.beginTransaction();
  transaction.run("MATCH ()-[r]-() DELETE r");
  transaction.run("MATCH (n) DETACH DELETE n");
  transaction.success();
  session.close();
}
 

@BeforeClass
public void prepareTest() throws IOException {

  testConfiguration = new ComponentConfigurator<>(Neo4jConfiguration.class).detectConfiguration( "Neo4jBoltPersistIT");
  testClient = Neo4jBoltClient.getInstance(testConfiguration);

  Session session = testClient.client().session();
  Transaction transaction = session.beginTransaction();
  transaction.run("MATCH ()-[r]-() DELETE r");
  transaction.run("MATCH (n) DETACH DELETE n");
  transaction.success();
  session.close();
}
 

@Override
public StreamsResultSet readAll() {

  Session session = null;

  String query = config.getQuery();
  Map<String, Object> params = mapper.convertValue(config.getParams(), Map.class);

  try {
    session = client.client().session();
    Transaction transaction = session.beginTransaction();

    this.statementResult = client.client().session().beginTransaction().run(query, params);

    while( statementResult.hasNext()) {
      Record record = statementResult.next();
      Optional<StreamsDatum> datum = buildDatum(record);
      if( datum.isPresent()) {
        write(datum.get());
      }
    }

  } catch(Exception ex) {
    LOGGER.warn("Exception", ex);
  } finally {
    if( session != null ) {
      session.close();
    }
  }
  return readCurrent();

}
 

@TransactionAttribute(REQUIRES_NEW)
public String getPerson(String name) {
    Session session = injectedDriver.session();
    try {
        StatementResult result = session.run("MATCH (a:Person) WHERE a.name = '" + name + "' RETURN a.name AS name, a.title AS title");
        if (result.hasNext()) {
            Record record = result.next();
            return record.toString();
        }
        return name + " not found";
    }
    finally {
        session.close();
    }
}
 

public String addPersonClassInstanceInjection() {
    Session session = injectedDriver.session();
    try {
        session.run("CREATE (a:Person {name:'CDI', title:'King'})");
        StatementResult result = session.run("MATCH (a:Person) WHERE a.name = 'CDI' RETURN a.name AS name, a.title AS title");


        Record record = result.next();
        return record.toString();
    } finally {
        session.run("MATCH (a:Person) delete a");
        session.close();
    }
}
 

public SubGraph query(String queryString) {

        if (queryString.matches("^[\\d\\s]+$")){ // 只有结点id构成的query
            List<Long> idList=new ArrayList<>();
            String[] eles = queryString.trim().split("\\s+");
            for (String e:eles)
                if (e.length()>0) {
                    Session session = context.connection.session();
                    long id=Long.parseLong(e);
                    String stat="match (n) where id(n)="+id+" return id(n)";
                    StatementResult rs = session.run(stat);
                    if (rs.hasNext()) {
                        idList.add(id);
                    }
                    session.close();
                }
            return idTest(idList);
        }

        /*
         * seedMap: - key: 定位到的代码元素结点的集合 - value: 这个集合的离散度，离散度越低，说明这个图的质量越好
		 */
        candidateMap.clear();// 清空candidateMap, 对于每个query即时生成
        scoreMap.clear();
        List<SubGraph> graphs = myFindSubGraphs(queryString);
        if (graphs.size() > 0) {
            if (debug)
                printGraphList(graphs);
            return graphs.get(0);
        }
        return new SubGraph();
    }
 

public static SubGraph run(SubGraph searchResult1, ApiLocatorContext context){
    SubGraph r = new SubGraph();
    r.getNodes().addAll(searchResult1.getNodes());
    r.cost = searchResult1.cost;
    Set<Long> flags = new HashSet<>();
    for (long seed1 : searchResult1.getNodes()) {
        if (flags.contains(seed1))
            continue;
        for (long seed2 : searchResult1.getNodes()) {
            if (seed1 == seed2)
                continue;
            if (flags.contains(seed2))
                continue;
            Session session = context.connection.session();
            String stat = "match p=shortestPath((n1)-[:" + codeRels + "*..10]-(n2)) where id(n1)=" + seed1 + " and id(n2)=" + seed2
                    + " unwind relationships(p) as r return id(startNode(r)), id(endNode(r)), id(r)";
            StatementResult rs = session.run(stat);
            while (rs.hasNext()) {
                Record item=rs.next();
                long node1 = item.get("id(startNode(r))").asLong();
                long node2 = item.get("id(endNode(r))").asLong();
                long rel = item.get("id(r)").asLong();
                r.getNodes().add(node1);
                r.getNodes().add(node2);
                r.getEdges().add(rel);
                flags.add(seed2);
            }
            session.close();
        }
        flags.add(seed1);
    }
    return r;
}
 

public static Neo4jNode get(long id, SnowGraphContext context){
    Neo4jNode node=null;
    Session session = context.getNeo4jBoltDriver().session();
    String stat = "match (n) where id(n)=" + id + " return id(n), labels(n)[0], n";
    StatementResult rs = session.run(stat);
    while (rs.hasNext()) {
        Record item=rs.next();
        node=new Neo4jNode(item.get("id(n)").asLong(),item.get("labels(n)[0]").asString());
        node.properties.putAll(item.get("n").asMap());
        node.properties.put("id",node.id);
        node.properties.put("label",node.label);
    }
    session.close();
    return node;
}
 

@Override
public void closeSession(Session session) {
	if(session != null && session.isOpen()) {
		session.close();
	}
}
 

public void index(boolean overWrite) throws IOException {

        if (!overWrite && new File(path).exists())
            return;

        Directory dir = FSDirectory.open(Paths.get(path));
        Analyzer analyzer = new EnglishAnalyzer();
        IndexWriterConfig iwc = new IndexWriterConfig(analyzer);
        iwc.setOpenMode(OpenMode.CREATE);
        IndexWriter writer = new IndexWriter(dir, iwc);

        Session session = context.connection.session();
        String stat = "match (n) where exists(n." + TextExtractor.IS_TEXT + ") and n." + TextExtractor.IS_TEXT + "=true return id(n), labels(n)[0], n." + TextExtractor.TITLE + ", n." + TextExtractor.TEXT;
        StatementResult rs = session.run(stat);
        int c=0;
        while (rs.hasNext()) {
            Record item = rs.next();
            String label=item.get("labels(n)[0]").asString();
            if (!(label.equals(StackOverflowExtractor.QUESTION)||label.equals(StackOverflowExtractor.ANSWER)||label.equals(JiraExtractor.ISSUE)))
                continue;
            String org_content = item.get("n." + TextExtractor.TEXT).asString();
            String title = item.get("n." + TextExtractor.TITLE).asString();
            String content = dealWithDocument("<html><title>" + title + "</title>" + org_content + "</html>");
            if (content.length() > 0) {
                Document document = new Document();
                long id=item.get("id(n)").asLong();
                document.add(new StringField("id", "" + id, Field.Store.YES));
                document.add(new StringField("type", item.get("labels(n)[0]").asString(), Field.Store.YES));
                document.add(new StringField("title", title, Field.Store.YES));
                document.add(new TextField("content", content, Field.Store.YES));
                document.add(new TextField("org_content", org_content, Field.Store.YES));
                Set<Long> nodes=new HashSet<>();
                Session session1=context.connection.session();
                StatementResult rs1=session1.run("match (a)-[:"+ ApiMentionExtractor.API_NAME_MENTION+"|"+ ReferenceExtractor.REFERENCE+"]->(b) where id(a)="+id+" and exists(b."+ LINEExtractor.LINE_VEC+") return distinct id(b)");
                while (rs1.hasNext()){
                    Record item1=rs1.next();
                    nodes.add(item1.get("id(b)").asLong());
                }
                session1.close();
                String nodeSet = StringUtils.join(nodes, " ").trim();
                document.add(new StringField("node_set", nodeSet, Field.Store.YES));
                writer.addDocument(document);
                System.out.println(c+": "+nodes.size());
                c++;
            }
        }
        session.close();

        writer.close();
    }
 

public SubGraph queryExpand(String queryString) {
    SubGraph r = new SubGraph();
    SubGraph searchResult1 = query(queryString);
    r.nodes.addAll(searchResult1.nodes);
    r.cost = searchResult1.cost;

    Set<Long> selected = new HashSet<>();
    selected.add(r.nodes.iterator().next());
    int rootCount = searchResult1.nodes.size() - 1;

    while(rootCount-- > 0){
        int minStep = Integer.MAX_VALUE;
        long candidate = 0;
        SubGraph path = null;
        for (long seed1 : selected){
            for (long seed2: searchResult1.nodes){
                if (selected.contains(seed2))
                    continue;
                SubGraph currentPath = new SubGraph();
                Session session = context.connection.session();
                String stat = "match p=shortestPath((n1)-[:" + codeRels + "*..10]-(n2)) where id(n1)=" + seed1 + " and id(n2)=" + seed2
                        + " unwind relationships(p) as r return id(startNode(r)), id(endNode(r)), id(r)";
                StatementResult rs = session.run(stat);
                while (rs.hasNext()) {
                    Record item=rs.next();
                    long node1 = item.get("id(startNode(r))").asLong();
                    long node2 = item.get("id(endNode(r))").asLong();
                    long rel = item.get("id(r)").asLong();
                    currentPath.nodes.add(node1);
                    currentPath.nodes.add(node2);
                    currentPath.edges.add(rel);
                }
                session.close(); // may have no path
                if (currentPath.edges.size() > 0 && currentPath.edges.size() < minStep){
                    minStep = currentPath.edges.size();
                    path = currentPath;
                    candidate = seed2;
                }
            }

        }
        if (path == null) // cannot expand to other nodes
            break;
        selected.add(candidate);
        r.nodes.addAll(path.nodes);
        r.edges.addAll(path.edges);
    }
    if(debug)
        System.out.println("expanded graph size: " + r.nodes.size()+"\n");
    return r;
}