graphdb/src/main/java/com/orientechnologies/orient/graph/graphml/OGraphMLReader.java
public OGraphMLReader inputGraph(final Graph inputGraph, final String filename, int bufferSize, String vertexIdKey,
      String edgeIdKey, String edgeLabelKey) throws IOException {
    FileInputStream fis = new FileInputStream(filename);
    try {
      return inputGraph(inputGraph, fis, bufferSize, vertexIdKey, edgeIdKey, edgeLabelKey);
    } finally {
      fis.close();
    }
  }
public OGraphMLReader inputGraph(final Graph inputGraph, final String filename, int bufferSize, String vertexIdKey,
      String edgeIdKey, String edgeLabelKey) throws IOException {
    FileInputStream fis = new FileInputStream(filename);
    try {
      return inputGraph(inputGraph, fis, bufferSize, vertexIdKey, edgeIdKey, edgeLabelKey);
    } finally {
      fis.close();
    }
  }
Input the GraphML stream data into the graph. More control over how data is streamed is provided by this method.

@param inputGraph
the graph to populate with the GraphML data
@param filename
name of a file containing GraphML data
@param bufferSize
the amount of elements to hold in memory before committing a transactions (only valid for TransactionalGraphs)
@param vertexIdKey
if the id of a vertex is a &lt;data/&gt; property, fetch it from the data property.
@param edgeIdKey
if the id of an edge is a &lt;data/&gt; property, fetch it from the data property.
@param edgeLabelKey
if the label of an edge is a &lt;data/&gt; property, fetch it from the data property.
@throws IOException
thrown when the GraphML data is not correctly formatted