### Question:
Edge { public boolean isChildRelation() { return RDFConstants.RDFS_SUBCLASSOF.equals(uri); } Edge(@JsonProperty("source") String source,
				@JsonProperty("target") String target,
				@JsonProperty("label") String label,
				@JsonProperty("uri") String uri); String getSource(); String getTarget(); String getLabel(); String getUri(); boolean isChildRelation();  }### Answer:
@Test public void isChildRelation_nullUri() { final Edge edge = new Edge("source", "target", "label", null); assertFalse(edge.isChildRelation()); }
@Test public void isChildRelation_notChildRelation() { final Edge edge = new Edge("source", "target", "label", "notAChild"); assertFalse(edge.isChildRelation()); }
@Test public void isChildRelation_isChildRelation() { final Edge edge = new Edge("source", "target", "label", RDFConstants.RDFS_SUBCLASSOF); assertTrue(edge.isChildRelation()); }