/*
    * Copyright (c) 2006 JMockit developers
    * This file is subject to the terms of the MIT license (see LICENSE.txt).
    */
   package mockit.internal.expectations.invocation;
   
   import edu.umd.cs.findbugs.annotations.NonNull;
   import edu.umd.cs.findbugs.annotations.Nullable;
   
  import java.util.Iterator;
  
  class InvocationResult {
      InvocationResult next;
  
      @Nullable
      Object produceResult(@NonNull Object[] args) throws Throwable {
          return null;
      }
  
      @Nullable
      Object produceResult(@Nullable Object invokedObject, @NonNull ExpectedInvocation invocation,
              @NonNull InvocationConstraints constraints, @NonNull Object[] args) throws Throwable {
          return produceResult(args);
      }
  
      static final class ReturnValueResult extends InvocationResult {
          @Nullable
          private final Object returnValue;
  
          ReturnValueResult(@Nullable Object returnValue) {
              this.returnValue = returnValue;
          }
  
          @Nullable
          @Override
          Object produceResult(@NonNull Object[] args) {
              return returnValue;
          }
      }
  
      static final class ThrowableResult extends InvocationResult {
          @NonNull
          private final Throwable throwable;
  
          ThrowableResult(@NonNull Throwable throwable) {
              this.throwable = throwable;
          }
  
          @NonNull
          @Override
          Object produceResult(@NonNull Object[] args) throws Throwable {
              throwable.fillInStackTrace();
              throw throwable;
          }
      }
  
      static final class DeferredResults extends InvocationResult {
          @NonNull
          private final Iterator<?> values;
  
          DeferredResults(@NonNull Iterator<?> values) {
              this.values = values;
          }
  
          @Nullable
          @Override
          Object produceResult(@NonNull Object[] args) throws Throwable {
              Object nextValue = values.hasNext() ? values.next() : null;
  
              if (nextValue instanceof Throwable) {
                  Throwable t = (Throwable) nextValue;
                  t.fillInStackTrace();
                  throw t;
              }
  
              return nextValue;
          }
      }
  }