package com.dooapp.gaedo.blueprints.transformers;
import com.dooapp.gaedo.blueprints.GraphUtils;
import com.dooapp.gaedo.blueprints.Kind;
import com.dooapp.gaedo.blueprints.Properties;
import com.dooapp.gaedo.blueprints.UnableToCreateException;
import com.dooapp.gaedo.utils.Utils;
import com.tinkerpop.blueprints.pgm.Graph;
import com.tinkerpop.blueprints.pgm.IndexableGraph;
import com.tinkerpop.blueprints.pgm.Vertex;
/**
* Helper class for literal transformer
* @author ndx
*
*/
public abstract class AbstractLiteralTransformer<Type> {
public Vertex getVertexFor(IndexableGraph database, Type value) {
Object vertexId = getVertexId(database, value);
// First try direct vertexId access
if(database.getVertex(vertexId)!=null) {
return database.getVertex(vertexId);
}
// Then indexed vertex id (for neo4j, typically)
Vertex returned = GraphUtils.locateVertex(database, Properties.vertexId.name(), vertexId);
// Finally create vertex
if(returned==null) {
returned = database.addVertex(vertexId);
returned.setProperty(Properties.value.name(), getVertexValue(value));
returned.setProperty(Properties.vertexId.name(), vertexId);
returned.setProperty(Properties.kind.name(), Kind.literal.name());
returned.setProperty(Properties.type.name(), value.getClass().getCanonicalName());
}
return returned;
}
public Type loadObject(Vertex key) {
String effectiveType = key.getProperty(Properties.type.name()).toString();
try {
Class valueClass = Class.forName(effectiveType);
return loadObject(valueClass, key);
} catch (ClassNotFoundException e) {
throw new UnableToCreateException(effectiveType, e);
}
}
public Type loadObject(Class valueClass, Vertex key) {
String valueString = key.getProperty(Properties.value.name()).toString();
return loadObject(valueClass, key, valueString);
}
protected Type loadObject(Class valueClass, Vertex key, String valueString) {
return (Type) Utils.fromString(valueString, valueClass);
}
/**
* Get vertex value for object. notice it is better to get it as a string than anything else
* @param value
* @return
*/
protected abstract Object getVertexValue(Type value);
/**
* Creates an id out of an object
* @param value
* @return
*/
public String getVertexId(Graph database, Type value) {
String idString = value.getClass().getCanonicalName()+":"+getVertexValue(value).toString();
return idString;
}
}