private void writeEdges(JsonWriter writer, List<Edge> edges, HiveConf conf)
      throws IOException, InstantiationException, IllegalAccessException, ClassNotFoundException {
    writer.name("edges");
    writer.beginArray();
    for (Edge edge: edges) {
      writer.beginObject();
      writer.name("sources");
      writer.beginArray();
      for (Vertex vertex: edge.sources) {
        writer.value(vertex.id);
      }
      writer.endArray();
      writer.name("targets");
      writer.beginArray();
      for (Vertex vertex: edge.targets) {
        writer.value(vertex.id);
      }
      writer.endArray();
      if (edge.expr != null) {
        writer.name("expression").value(HookUtils.redactLogString(conf, edge.expr));
      }
      writer.name("edgeType").value(edge.type.name());
      writer.endObject();
    }
    writer.endArray();
  }
Write out an JSON array of edges.
ql/src/java/org/apache/hadoop/hive/ql/hooks/LineageLogger.java