NullPointerException reading json

[francetem]

While doing:

       JcQueryResult jcQueryResult = dbAccess.execute(nodeQuery);
        return jcQueryResult.resultOf(r);

I get a null pointer exception:

java.lang.NullPointerException at iot.jcypher.query.result.util.ResultHandler$ElementInfo.access$000(ResultHandler.java:930) at iot.jcypher.query.result.util.ResultHandler.getRelations(ResultHandler.java:238)

For what I see in the code:

         if (obj.getValueType() == ValueType.OBJECT) {
            JsonObject restObject = (JsonObject)obj;
            if (restObject.containsKey("self")) {
                String selfString = restObject.getString("self");
                if (selfString != null) {
                    ElementInfo ei = ElementInfo.parse(selfString);
                    return ei;
                }
            }
        } else if (obj.getValueType() == ValueType.NULL) {
            ElementInfo ei = ElementInfo.nullElement();
            return ei;
        }

The ValueType returned is Array and it is coming from the json result:

"results": [{
        "columns": ["r"],
        "data": [{
            "rest": [[{
                "start": "http://localhost:7474/db/data/node/6317228",

...

Maybe I'm doing something wrong however.

[Wolfgang-Schuetzelhofer]

Hi,

which JCypher release are you using? Can you provide me the complete JcQuery (the clauses that make up the query)? Do you have some sample data?

Best regards, Wolfgang

[francetem]

Hi Wolfgang.

My jcypher dependency is:

    <dependency>
        <groupId>net.iot-solutions.graphdb</groupId>
        <artifactId>jcypher</artifactId>
        <version>3.2.0</version>
    </dependency>

As I'm testing jcypher I have created the following client class:

public class JCypherClient {

    public static final String BOOKING_LABEL = "Booking";
    public static final String ID_PARAMETER = "id";
    public static final String EMAIL_LABEL = "Email";
    public static final String EMAIL_PROPERTY = "email";

    public void insertBooking(Booking booking) {

        JcNode b = new JcNode("b");
        JcNode e = new JcNode("e");

        JcQuery nodeQuery = new JcQuery();
        nodeQuery.setClauses(new IClause[]{
                        MERGE.node(b).label(BOOKING_LABEL).property(ID_PARAMETER).value(booking.getId()),
                        DO.SET(b.property("fraud")).to(booking.getFraud()),
                        DO.SET(b.property("status")).to(booking.getStatus()),
                        MERGE.node(e).label(EMAIL_LABEL).property(EMAIL_PROPERTY).value(booking.getEmail())
                }
        );

        JcQuery relationQuery = new JcQuery();
        relationQuery.setClauses(new IClause[]{
                        MATCH.node(b).label(BOOKING_LABEL).property(ID_PARAMETER).value(booking.getId()),
                        MATCH.node(e).label(EMAIL_LABEL).property("email").value(booking.getEmail()),
                        MERGE.node(b).relation().type("WITH_EMAIL").node(e)
                }
        );

        IDBAccess dbAccess = createDbAccess();
        dbAccess.execute(Arrays.asList(nodeQuery, relationQuery));
        dbAccess.close();
    }

    public List<GrRelation> getBookingsRelated(Long bookingId, int maxHops) {
        IDBAccess dbAccess = createDbAccess();
        JcQuery nodeQuery = new JcQuery();
        JcNode b = new JcNode("b");
        JcNode b2 = new JcNode("b2");
        JcRelation r = new JcRelation("r");
        nodeQuery.setClauses(new IClause[]{
                MATCH.node(b).label(BOOKING_LABEL).property(ID_PARAMETER).value(bookingId).relation(r).maxHops(maxHops).node(b2),
                RETURN.DISTINCT().value(r)
        });
        return dbAccess.execute(nodeQuery).resultOf(r);
    }

    private IDBAccess createDbAccess() {
        Properties props = new Properties();
        props.setProperty(DBProperties.SERVER_ROOT_URI, "http://localhost:7474");
        return DBAccessFactory.createDBAccess(DBType.REMOTE, props, "neo4j", "admin");
    }

}

And the test that I'm launching is the following one:

public class JCypherClientTest {

    JCypherClient jCypherClient = new JCypherClient();

    @Test
    public void testInsertBooking(){
        jCypherClient.insertBooking(new Booking(1l,"FRAUD","CONTRACT", "iam@fraudst.er"));
        jCypherClient.insertBooking(new Booking(2l,"LEGIT","INIT", "iam@fraudst.er"));
    }

    @Test
    public void testGetGraph(){
        List<GrRelation> bookingsRelated = jCypherClient.getBookingsRelated(1L, 6);

    }
}

The stack trace:

java.lang.NullPointerException at iot.jcypher.query.result.util.ResultHandler$ElementInfo.access$000(ResultHandler.java:930) at iot.jcypher.query.result.util.ResultHandler.getRelations(ResultHandler.java:238) at iot.jcypher.query.result.util.ResultHandler.getRelations(ResultHandler.java:219) at iot.jcypher.query.JcQueryResult.resultOf(JcQueryResult.java:76)

[francetem]

public class Booking {
    private final Long id;
    private final String fraud;
    private final String status;
    private final String email;

    public Booking(Long id, String fraud, String status, String email) {
        this.id = id;
        this.fraud = fraud;
        this.status = status;
        this.email = email;
    }

    public Long getId() {
        return id;
    }

    public String getFraud() {
        return fraud;
    }

    public String getStatus() {
        return status;
    }

    public String getEmail() {
        return email;
    }
}

[Wolfgang-Schuetzelhofer]

Hi,

I have built a new JCypher release 3.2.1 which should fix your problem. It may take a couple of hours until the release is visible on maven central (distribution to all repository servers takes some time).

I hope I could help you, best regards, Wolfgang

[francetem]

Thank you very much Wolgang

Regards.