### Question:
StringSubstitutionEngine implements StringSubstitutor { @Override public StringsubsDefinition getStringSubsDefinition() { return _root; } StringSubstitutionEngine(InputStream inputStream); @Override void setAttributePreprocessor(AttributePreprocessor attributePreprocessor); @Override void setEntryFactory(SubstitutableFactory factory); @Override void setFileBackupLocation(File backupLocation); @Override List<Property> getDefaultProperties(PropertyType type); @Override void substituteAll(); @Override void substituteComponents(List<String> components); @Override void substituteGroups(List<String> groups); @Override StringsubsDefinition getStringSubsDefinition();  }### Answer:
@Test public void testXMLLoading() { StringsubsDefinition def = _engine.getStringSubsDefinition(); Assert.assertNotNull(def); Assert.assertNotNull(def.getComponent()); Assert.assertEquals(def.getComponent().size(), 2); Assert.assertNotNull(def.getVersion()); Assert.assertFalse(def.getChangePair().isEmpty()); }