### Question:
Revision implements Serializable { public Revision incrementRevision(final String clientId) { return new Revision(version + 1, clientId, componentId); } Revision(Long version, String clientId, String componentId); String getClientId(); Long getVersion(); String getComponentId(); Revision incrementRevision(final String clientId); @Override boolean equals(final Object obj); @Override int hashCode(); @Override String toString();  }### Answer:
@Test public void testIncrementRevision() throws Exception { final String clientId = "client-id"; final String componentId = "component-id"; final Revision revision = new Revision(0l, clientId, componentId); final Revision updatedRevision = revision.incrementRevision(clientId); assertEquals(1, updatedRevision.getVersion().longValue()); assertEquals(clientId, updatedRevision.getClientId()); assertEquals(componentId, updatedRevision.getComponentId()); }