@Test
    public void shouldDumpStringSize() {
        final Map<String, String> content = new HashMap();
        content.put("a", "123456");
        content.put("b", "567890");
        final ObjectWritable object = new ObjectWritable(content);
        final String f = object.toString();
        assertTrue(f.startsWith(content.getClass().toString()));
        assertTrue(f.endsWith(content.size()+""));
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
hadoop-gremlin/src/test/java/org/apache/tinkerpop/gremlin/hadoop/structure/io/ObjectWritableTest.java