@Test
  public void testDoubleObject() throws Exception {
    Double value = getRandom().nextDouble();

    DataOutputStream out = getDataOutput();
    DataSerializer.writeObject(value, out);
    out.flush();

    DataInput in = getDataInput();
    Double value2 = DataSerializer.readObject(in);
    assertEquals(value, value2);
  }
Tests data serializing a {@link Double} using {@link DataSerializer#writeObject}.
geode-core/src/test/java/org/apache/geode/internal/DataSerializableJUnitTest.java