Thanks How I can call the function when i do this way op.createTheGraph(); op.knowsLikesTraverser(A); it seems wrong.
On Thursday, April 17, 2014 3:56:44 AM UTC-7, Anders Nawroth wrote: > > Hi! > > Did you initialize the db field? > > Something like > db = new GraphDatabaseFactory().newEmbeddedDatabase( "path/to/db" ); > > /anders > > > On Thu, Apr 17, 2014 at 9:11 AM, Tingting Cui <[email protected]<javascript:> > > wrote: > >> when i try to run TraversalExample.java example and create the graph like >> this >> it give me error like this >> Exception in thread "main" java.lang.NullPointerException >> at setupneo4j.TraversalExample.<init>(TraversalExample.java:23) >> at setupneo4j.TraversalExample.main(TraversalExample.java:33) >> what is the problems here. >> public static void main( String[] args ) >> { >> >> TraversalExample op = new TraversalExample( db ); >> op.shutdownGraph(); >> } >> public void shutdownGraph() >> { >> try >> { >> if ( db != null ) >> { >> db.shutdown(); >> } >> } >> finally >> { >> db = null; >> } >> } >> >> public Node createTheGraph() >> { >> try ( Transaction tx = db.beginTx() ) >> { >> // START SNIPPET: createGraph >> Node A = db.createNode(); >> Node B = db.createNode(); >> Node C = db.createNode(); >> Node D = db.createNode(); >> >> A.createRelationshipTo( C, Rels.KNOWS ); >> C.createRelationshipTo( D, Rels.KNOWS ); >> A.createRelationshipTo( B, Rels.KNOWS); >> B.createRelationshipTo( C, Rels.KNOWS ); >> // END SNIPPET: createGraph >> A.setProperty( "name", "A" ); >> B.setProperty( "name", "B" ); >> C.setProperty( "name", "C" ); >> D.setProperty( "name", "D" ); >> tx.success(); >> return A; >> } >> } >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Neo4j" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> For more options, visit https://groups.google.com/d/optout. >> > > > > -- > Anders Nawroth [[email protected] <javascript:>] > Skype: anders.nawroth > -- You received this message because you are subscribed to the Google Groups "Neo4j" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
