@Test
    public void shouldSupplySameConstantOnEachInvocation() {
        final String l1 = constant.get();
        final String l2 = constant.get();
        final String l3 = constant.get();

        assertSame(l1, l2);
        assertSame(l1, l3);
        assertSame(l2, l3);
    }
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/util/function/ConstantSupplierTest.java