How to store tree structure using neo4j and gremlin
I want to store following directory tree structure using neo4j
local database and Gremlin
in Java.
(ROOT) / \ Dir2 Dir3 开发者_如何转开发 / \ \ Dir4 Dir5 Dir6 / Dir7
I have defined a method StorePath(String path).
What i want : When i call StorePath(path) with path = "Root\Dir2\Dir4\Dir7" then data should be stored as followsRoot / Dir2 / Dir4 / Dir7
where Root and Dir* are vertices with blank edges. Please help me with the java code.
private static final RelationshipType SUB_DIR = DynamicRelationshipType.withName("SUB_DIR");
public void storePath(String path) {
Node dir = graphDb.getReferenceNode();
for (String name : path.split(File.separator)) {
dir = obtainSubDir(dir, name);
}
}
private Node obtainSubDir(Node dir, String name) {
Node subDir = getSubDir(dir,name);
if (subDir!=null) return subDir;
return createSubDir(dir, name);
}
private Node getSubDir(Node dir, String name) {
for (Relationship rel : dir.getRelationships(SUB_DIR, Direction.OUTGOING)) {
final Node subDir = rel.getEndNode();
if (subDir.getProperty("name", "").equals(name)) return subDir;
}
return null;
}
private Node createSubDir(Node dir, String name) {
Node subDir = dir.getGraphDatabase().createNode();
subDir.setProperty("name", name);
dir.createRelationshipTo(subDir, SUB_DIR);
return subDir;
}
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