gistfile1.java

package com.tinkerpop.blueprints.util.wrappers.batch.cache;

import com.tinkerpop.blueprints.Graph;
import com.tinkerpop.blueprints.Vertex;

import java.util.HashMap;
import java.util.Map;

/**
 * (c) Matthias Broecheler ([email protected])
 */

public class ObjectIDVertexCache implements VertexCache {

    private static final int INITIAL_CAPACITY = 1000;

    private final Graph graph;
    private final Map<Object, Object> map;
    private final List<Object> newlyAddedKeys;

    public ObjectIDVertexCache(final Graph graph) {
        if (graph == null) throw new IllegalArgumentException("Graph expected.");
        this.graph = graph;
        map = new HashMap<Object, Object>(INITIAL_CAPACITY);
        newlyAddedKeys = new List<Object>();
    }


    @Override
    public Vertex getVertex(Object externalID) {
        Object o = map.get(externalID);
        if (o instanceof Vertex) {
            return (Vertex) o;
        } else if (o != null) { //o is the internal id
            Vertex v = graph.getVertex(o);
            map.put(externalID, o);
            return v;
        } else return null;
    }

    @Override
    public void add(Vertex vertex, Object externalID) {
        assert !map.containsKey(externalID);
        map.put(externalID, vertex);
        newlyAddedKeys.add(externalID);
    }

    @Override
    public void newTransaction() {
        for (Object newKey : newlyAddedKeys) {
            Vertex v = (Vertex) map.get(newKey);
            entry.setValue(v.getId());
        }
        newlyAddedKeys.clear();
    }
}