g.writeArrayFieldStart("generations");
for (int level = 0; level < generations.length; level++)
{
g.writeStartObject();
g.writeNumberField("generation", level);
g.writeArrayFieldStart("members");
for (SSTableReader ssTableReader : generations[level])
g.writeNumber(ssTableReader.descriptor.generation);
g.writeEndArray(); // members
g.writeEndObject(); // generation