Examples with SubgraphMapper org.neo4j.visualization.SubgraphMapper used on opensource projects

Example 1 with SubgraphMapper

use of org.neo4j.visualization.SubgraphMapper in project neo4j-documentation by neo4j.

the class TestGraphvizSubgraphOutput method testSimpleGraph.

@Test
public void testSimpleGraph() throws Exception {
    Path folder = Path.of("target/example-db" + System.nanoTime());
    DatabaseManagementService managementService = new DatabaseManagementServiceBuilder(folder).build();
    try {
        GraphDatabaseService neo = managementService.database(DEFAULT_DATABASE_NAME);
        try (Transaction tx = neo.beginTx()) {
            final Node emil = tx.createNode();
            emil.setProperty("name", "Emil Eifrém");
            emil.setProperty("country_of_residence", "USA");
            final Node tobias = tx.createNode();
            tobias.setProperty("name", "Tobias Ivarsson");
            tobias.setProperty("country_of_residence", "Sweden");
            final Node johan = tx.createNode();
            johan.setProperty("name", "Johan Svensson");
            johan.setProperty("country_of_residence", "Sweden");
            final Relationship emilKNOWStobias = emil.createRelationshipTo(tobias, type.KNOWS);
            final Relationship johanKNOWSemil = johan.createRelationshipTo(emil, type.KNOWS);
            final Relationship tobiasKNOWSjohan = tobias.createRelationshipTo(johan, type.KNOWS);
            final Relationship tobiasWORKS_FORemil = tobias.createRelationshipTo(emil, type.WORKS_FOR);
            OutputStream out = new ByteArrayOutputStream();
            SubgraphMapper subgraphMapper = node -> {
                if (node.hasProperty("country_of_residence")) {
                    return (String) node.getProperty("country_of_residence");
                }
                return null;
            };
            GraphvizWriter writer = new GraphvizWriter();
            SubgraphMapper.SubgraphMappingWalker walker = new SubgraphMapper.SubgraphMappingWalker(subgraphMapper) {

                @Override
                protected Iterable<Node> nodes() {
                    return asList(emil, tobias, johan);
                }

                @Override
                protected Iterable<Relationship> relationships() {
                    return asList(emilKNOWStobias, johanKNOWSemil, tobiasKNOWSjohan, tobiasWORKS_FORemil);
                }
            };
            writer.emit(out, walker);
            tx.commit();
        }
    } finally {
        managementService.shutdown();
        deleteDirectory(folder.toFile());
    }
}