### Question:
Procedures implements InstructionSet { @Override public Executor getExecutor (String instructionName) { Procedure procedure = mProcedures.get (instructionName); return procedure != null ? new ProcedureExecutor (procedure, mRunner, mPublisher) : null; } Procedures(ProcedureRunner runner, TestRunResultPublisher publisher); void add(Procedure procedure); @Override String getName(); @Override void setup(); @Override Executor getExecutor(String instructionName); @Override void cleanup();  }### Answer:
@Test public void testGetExecutorUnknownProcedure () { Procedures procedures = new Procedures (null, null); String PROCEDURE_NAME = "unknown procedure"; assertNull (procedures.getExecutor (PROCEDURE_NAME)); }