IdentityRemoveStrategy.java

public final class IdentityRemovalStrategy extends AbstractTraversalStrategy<TraversalStrategy.OptimizationStrategy> implements TraversalStrategy.OptimizationStrategy {

    private static final IdentityRemovalStrategy INSTANCE = new IdentityRemovalStrategy();

    private IdentityRemovalStrategy() {
    }

    @Override
    public void apply(final Traversal.Admin<?, ?> traversal) {
        if (traversal.getSteps().size() <= 1)
            return;

        for (final IdentityStep<?> identityStep : TraversalHelper.getStepsOfClass(IdentityStep.class, traversal)) {
            if (identityStep.getLabels().isEmpty() || !(identityStep.getPreviousStep() instanceof EmptyStep)) {
                TraversalHelper.copyLabels(identityStep, identityStep.getPreviousStep(), false);
                traversal.removeStep(identityStep);
            }
        }
    }
  
    @Override
    public void apply(final Bytecode bytecode) {
        if (bytecode.getStepInstructions().size() <= 1)
            return;

        for (final Instruction identityInstruction : BytecodeHelper.getInstructionsOfOperator("identity", bytecode)) {
            if (!identityInstruction.getNextInstruction().getOperator().equals("as") || !(identityInstruction.getPreviousInstruction() instanceof NoOp)) {
                BytecodeHelper.removeInstruction(identityInstruction, bytecode);
            }
        }
    }

    public static IdentityRemovalStrategy instance() {
        return INSTANCE;
    }
}

IdentityRemoveStrategy.py

class IdentityRemoveStrategy(TraversalStrategy):
    def __init__(self):
        TraversalStrategy.__init__(self)
    
    def apply(obj):
      return __apply_traversal(obj) if isinstance(obj,traversal) else __apply_bytecode(obj)
    
    def __apply_traversal(traversal):
      return
    
    def __apply_bytecode(bytecode):
      if len(bytecode.step_instructions) <= 1:
        return
      for inst in BytecodeHelper.get_instructions_of_operator("identity", bytecode):
        if inst.next_instruction().operator is not "as" or inst.prev_instruction() is not NoOp:
          BytecodeHelper.remove_instruction(inst, bytecode)