### Question:
IngestSourceManagerImpl implements IngestSourceManager { @Override public IngestSource getIngestSourceById(String id) { return idToSource.get(id); }  void init(); @Override List<IngestSource> listSources(PID target); @Override List<IngestSourceCandidate> listCandidates(PID destination); @Override IngestSource getIngestSourceById(String id); @Override IngestSource getIngestSourceForUri(URI uri); void setConfigPath(String configPath); void setMappingPath(String mappingPath); void setContentPathFactory(ContentPathFactory contentPathFactory);  }### Answer:
@Test public void testGetIngestSourceByIdExists() throws Exception { configPath = createConfigFile(createBasicConfig("testsource", destPid)); initializeManager(); IngestSource source = sourceMan.getIngestSourceById("testsource"); assertEquals("testsource", source.getId()); }
@Test public void testGetIngestSourceByIdDoesNotExist() throws Exception { configPath = createConfigFile(createBasicConfig("testsource", destPid)); initializeManager(); IngestSource source = sourceMan.getIngestSourceById("wutsource"); assertNull(source); }