public MethodExecutor resolve(
     EvaluationContext context, Object targetObject, String name, Class<?>[] arguments)
     throws AccessException {
   if (name.equals("hasRole")) {
     return new HasRoleExecutor(context.getTypeConverter());
   }
   return null;
 }
예제 #2
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 /**
  * Determines if there is a type converter available in the specified context and attempts to use
  * it to convert the supplied value to the specified type. Throws an exception if conversion is
  * not possible.
  *
  * @param context the evaluation context that may define a type converter
  * @param typedValue the value to convert and a type descriptor describing it
  * @param targetType the type to attempt conversion to
  * @return the converted value
  * @throws EvaluationException if there is a problem during conversion or conversion of the value
  *     to the specified type is not supported
  */
 @SuppressWarnings("unchecked")
 public static <T> T convertTypedValue(
     EvaluationContext context, TypedValue typedValue, Class<T> targetType) {
   Object value = typedValue.getValue();
   if ((targetType == null)
       || (value != null && ClassUtils.isAssignableValue(targetType, value))) {
     return (T) value;
   }
   if (context != null) {
     return (T)
         context
             .getTypeConverter()
             .convertValue(
                 value, typedValue.getTypeDescriptor(), TypeDescriptor.valueOf(targetType));
   }
   throw new EvaluationException(
       "Cannot convert value '" + value + "' to type '" + targetType.getName() + "'");
 }
  /**
   * Locate a constructor on the type. There are three kinds of match that might occur:
   *
   * <ol>
   *   <li>An exact match where the types of the arguments match the types of the constructor
   *   <li>An in-exact match where the types we are looking for are subtypes of those defined on the
   *       constructor
   *   <li>A match where we are able to convert the arguments into those expected by the
   *       constructor, according to the registered type converter.
   * </ol>
   */
  @Override
  public ConstructorExecutor resolve(
      EvaluationContext context, String typename, List<TypeDescriptor> argumentTypes)
      throws AccessException {

    try {
      TypeConverter typeConverter = context.getTypeConverter();
      Class<?> type = context.getTypeLocator().findType(typename);
      Constructor<?>[] ctors = type.getConstructors();

      Arrays.sort(
          ctors,
          new Comparator<Constructor<?>>() {
            @Override
            public int compare(Constructor<?> c1, Constructor<?> c2) {
              int c1pl = c1.getParameterTypes().length;
              int c2pl = c2.getParameterTypes().length;
              return (new Integer(c1pl)).compareTo(c2pl);
            }
          });

      Constructor<?> closeMatch = null;

      for (Constructor<?> ctor : ctors) {
        Class<?>[] paramTypes = ctor.getParameterTypes();
        List<TypeDescriptor> paramDescriptors = new ArrayList<TypeDescriptor>(paramTypes.length);
        for (int i = 0; i < paramTypes.length; i++) {
          paramDescriptors.add(new TypeDescriptor(new MethodParameter(ctor, i)));
        }
        ReflectionHelper.ArgumentsMatchInfo matchInfo = null;
        if (ctor.isVarArgs() && argumentTypes.size() >= paramTypes.length - 1) {
          // *sigh* complicated
          // Basically.. we have to have all parameters match up until the varargs one, then the
          // rest of what is
          // being provided should be
          // the same type whilst the final argument to the method must be an array of that (oh, how
          // easy...not) -
          // or the final parameter
          // we are supplied does match exactly (it is an array already).
          matchInfo =
              ReflectionHelper.compareArgumentsVarargs(
                  paramDescriptors, argumentTypes, typeConverter);
        } else if (paramTypes.length == argumentTypes.size()) {
          // worth a closer look
          matchInfo =
              ReflectionHelper.compareArguments(paramDescriptors, argumentTypes, typeConverter);
        }
        if (matchInfo != null) {
          if (matchInfo.isExactMatch()) {
            return new ReflectiveConstructorExecutor(ctor);
          } else if (matchInfo.isCloseMatch() || matchInfo.isMatchRequiringConversion()) {
            closeMatch = ctor;
          }
        }
      }

      return (closeMatch != null ? new ReflectiveConstructorExecutor(closeMatch) : null);
    } catch (EvaluationException ex) {
      throw new AccessException("Failed to resolve constructor", ex);
    }
  }
 @Override
 public TypeConverter getTypeConverter() {
   return delegate.getTypeConverter();
 }
  @Override
  public void write(EvaluationContext context, Object target, String name, Object newValue)
      throws AccessException {
    if (target == null) {
      throw new AccessException("Cannot write property on null target");
    }
    Class<?> type = (target instanceof Class ? (Class<?>) target : target.getClass());

    Object possiblyConvertedNewValue = newValue;
    TypeDescriptor typeDescriptor = getTypeDescriptor(context, target, name);
    if (typeDescriptor != null) {
      try {
        possiblyConvertedNewValue =
            context
                .getTypeConverter()
                .convertValue(newValue, TypeDescriptor.forObject(newValue), typeDescriptor);
      } catch (EvaluationException evaluationException) {
        throw new AccessException("Type conversion failure", evaluationException);
      }
    }
    PropertyCacheKey cacheKey = new PropertyCacheKey(type, name, target instanceof Class);
    Member cachedMember = this.writerCache.get(cacheKey);

    if (cachedMember == null || cachedMember instanceof Method) {
      Method method = (Method) cachedMember;
      if (method == null) {
        method = findSetterForProperty(name, type, target);
        if (method != null) {
          cachedMember = method;
          this.writerCache.put(cacheKey, cachedMember);
        }
      }
      if (method != null) {
        try {
          ReflectionUtils.makeAccessible(method);
          method.invoke(target, possiblyConvertedNewValue);
          return;
        } catch (Exception ex) {
          throw new AccessException(
              "Unable to access property '" + name + "' through setter method", ex);
        }
      }
    }

    if (cachedMember == null || cachedMember instanceof Field) {
      Field field = (Field) cachedMember;
      if (field == null) {
        field = findField(name, type, target);
        if (field != null) {
          cachedMember = field;
          this.writerCache.put(cacheKey, cachedMember);
        }
      }
      if (field != null) {
        try {
          ReflectionUtils.makeAccessible(field);
          field.set(target, possiblyConvertedNewValue);
          return;
        } catch (Exception ex) {
          throw new AccessException("Unable to access field '" + name + "'", ex);
        }
      }
    }

    throw new AccessException("Neither setter method nor field found for property '" + name + "'");
  }