java.lang.reflect.Parameter#getParameterizedType ( )源码实例Demo

private Schema createSchemaFromParameter(Parameter parameter, String parameterName) {
	Schema schema;
	Class<?> clazz = parameter.getType();
	Annotation[] annotations = parameter.getAnnotations();

	if (clazz.isPrimitive()) {
		schema = schemaGeneratorHelper.parseBaseTypeSignature(clazz, annotations);
	} else if (clazz.isArray()) {
		schema = schemaGeneratorHelper.parseArraySignature(clazz.getComponentType(), null, annotations);
	} else if (clazz.isAssignableFrom(List.class)) {
		if (parameter.getParameterizedType() instanceof ParameterizedType) {
			Class<?> listGenericParameter = (Class<?>)((ParameterizedType) parameter.getParameterizedType()).getActualTypeArguments()[0];
			return schemaGeneratorHelper.parseArraySignature(listGenericParameter, null, annotations);
		}

		throw new IllegalArgumentException(String.format("List [%s] not being parametrized type.", parameterName));
	} else {
		schema = schemaGeneratorHelper.parseClassRefTypeSignature(clazz, annotations, null);
	}
	return schema;
}
 

private void fillParameterInfo(AbstractSerializableParameter<?> oasParameter, Parameter parameter, String parameterName) {
	Class<?> clazz = parameter.getType();
	Annotation[] annotations = parameter.getAnnotations();

	if (clazz.isPrimitive()) {
		setParameterDetails(oasParameter, clazz, annotations);
	} else if (clazz.isArray()) {
		oasParameter.setProperty(parseArraySignatureForParameter(clazz.getComponentType(), annotations));
	} else if (clazz.isAssignableFrom(List.class)) {
		if (!(parameter.getParameterizedType() instanceof ParameterizedType)) {
			throw new IllegalArgumentException(String.format("List [%s] not being parametrized type.", parameterName));
		}
		Class<?> listGenericParameter = (Class<?>) ((ParameterizedType) parameter.getParameterizedType()).getActualTypeArguments()[0];
		oasParameter.setProperty(parseArraySignature(listGenericParameter, null, annotations));
	} else {
		setParameterDetails(oasParameter, clazz, annotations);
	}
}
 

public Class<?> getParameterGenericType() {
    if (parameterGenericType == null) {
        Parameter parameter = getParameter();

        Type parameterType = parameter.getParameterizedType();
        if (!ParameterizedType.class.isAssignableFrom(parameterType.getClass())) {
            throw new PippoRuntimeException("Please specify a generic parameter type for '{}' of '{}'",
                getParameterName(), LangUtils.toString(method));
        }

        ParameterizedType parameterizedType = (ParameterizedType) parameterType;
        try {
            parameterGenericType = (Class<?>) parameterizedType.getActualTypeArguments()[0];
        } catch (ClassCastException e) {
            throw new PippoRuntimeException("Please specify a generic parameter type for '{}' of '{}'",
                getParameterName(), LangUtils.toString(method));
        }
    }

    return parameterGenericType;
}
 

private String parameterTypesFor(final Method method) {
  final StringBuilder builder = new StringBuilder();

  String separator = ", ";
  int parameterIndex = 0;
  final Parameter[] parameters = method.getParameters();

  for (final Parameter parameter : parameters) {
    final Type type = parameter.getParameterizedType();
    builder.append(type.getTypeName().replace('$', '.'));
    if (++parameterIndex < parameters.length) {
      builder.append(separator);
    }
  }

  return builder.toString();
}
 

private void deserializeBody(Method method, HttpRequest request) throws IOException {
    String contentType = HttpRequestUtils.contentType(request);
    if (contentType == null) return;

    String[] mediaTypeTokens = contentType.split("/", 2);
    if (mediaTypeTokens.length == 2) {
        MediaType mediaType = new MediaType(mediaTypeTokens[0], mediaTypeTokens[1]);
        Parameter[] parameters = method != null ? method.getParameters() : new Parameter[0];
        BodyDeserializable bodyDeserializable = BodyDeserializable.class.cast(request);
        for (Parameter parameter : parameters) {
            Class<?> type = parameter.getType();
            Type genericType = parameter.getParameterizedType();

            if (parameterInjectors.stream().anyMatch(injector-> injector.isApplicable(type, request)))
                continue;

            Object body = deserialize(request, type, genericType, mediaType);
            bodyDeserializable.setDeserializedBody(body);
        }
        if (bodyDeserializable.getDeserializedBody() == null) {
            bodyDeserializable.setDeserializedBody(deserialize(request, Object.class, Object.class, mediaType));
        }
    }
}
 

protected Map<Integer, Class<?>> prepareOptionalGenericTypeMap(Method executeMethod) {
    final Parameter[] parameters = executeMethod.getParameters();
    if (parameters.length == 0) {
        return Collections.emptyMap();
    }
    final Map<Integer, Class<?>> optionalGenericTypeMap = new LinkedHashMap<Integer, Class<?>>(4);
    int index = 0;
    for (Parameter parameter : parameters) {
        if (isOptionalParameterType(parameter.getType())) {
            final Type paramedType = parameter.getParameterizedType();
            final Class<?> genericType = DfReflectionUtil.getGenericFirstClass(paramedType);
            checkExecuteMethodOptionalParameter(executeMethod, paramedType, genericType);
            optionalGenericTypeMap.put(index, genericType);
        }
        ++index;
    }
    return Collections.unmodifiableMap(optionalGenericTypeMap);
}
 

protected void checkNonGenericParameter(Method executeMethod, Parameter parameter) {
    if (isNonGenericCheckTargetType(parameter.getType())) { // e.g. List
        final Type paramedType = parameter.getParameterizedType();
        if (paramedType == null) { // no way? no check just in case
            return;
        }
        if (paramedType instanceof ParameterizedType) {
            final Type[] typeArgs = ((ParameterizedType) paramedType).getActualTypeArguments();
            if (typeArgs != null && typeArgs.length > 0 && "?".equals(typeArgs[0].getTypeName())) { // e.g. List<?>
                throwActionFormWildcardOnlyListParameterException(executeMethod, parameter);
            }
        } else {
            throwActionFormNonGenericListParameterException(executeMethod, parameter);
        }
    }
}
 

protected static Map<Integer, Class<?>> prepareOptionalGenericTypeMap(Method executeMethod) {
    final Parameter[] parameters = executeMethod.getParameters();
    if (parameters.length == 0) {
        return Collections.emptyMap();
    }
    final Map<Integer, Class<?>> optionalGenericTypeMap = new LinkedHashMap<Integer, Class<?>>(4);
    int index = 0;
    for (Parameter parameter : parameters) {
        if (isOptionalParameterType(parameter.getType())) {
            final Type paramedType = parameter.getParameterizedType();
            final Class<?> genericType = DfReflectionUtil.getGenericFirstClass(paramedType);
            optionalGenericTypeMap.put(index, genericType);
        }
        ++index;
    }
    return Collections.unmodifiableMap(optionalGenericTypeMap);
}
 

private Class<?> getGenericParam(Parameter parameter) {
	if (parameter.getParameterizedType() instanceof ParameterizedType) {
		ParameterizedType parameterizedType = (ParameterizedType) parameter.getParameterizedType();
		if (isNotEmpty(parameterizedType.getActualTypeArguments())) {
			return (Class<?>) parameterizedType.getActualTypeArguments()[0];
		}
	}
	return null;
}
 

private Class<?> getGenericParam(Parameter parameter) {
	if (parameter.getParameterizedType() instanceof ParameterizedType) {
		ParameterizedType parameterizedType = (ParameterizedType) parameter.getParameterizedType();
		if (isNotEmpty(parameterizedType.getActualTypeArguments())) {
			return (Class<?>) parameterizedType.getActualTypeArguments()[0];
		}
	}
	return null;
}
 

@Override
public ParameterModel parse(Parameter parameter, ParamJavadoc paramJavadoc, ParameterModel parameterModel) {
    parameterModel.setName(getParameterName(parameter));

    if (paramJavadoc != null)
    {
        parameterModel.setDescription(FormatUtils.format(paramJavadoc.getComment()));
    }
    // 参数是Optional类型
    Type actualParamType = parameter.getParameterizedType();
    if (parameter.getType() == Optional.class)
    {
        if (parameter.getParameterizedType() instanceof ParameterizedType)
        {
            actualParamType = ((ParameterizedType)parameter.getParameterizedType()).getActualTypeArguments()[0];
        }
        else
        {
            throw new RuntimeException("why?");
        }
    }
    parameterModel.setParameterType(actualParamType);

    parameterModel.setLocation(getParameterLocation(parameter, actualParamType));
    parameterModel = parseInternal(parameter, actualParamType, parameterModel);
    parameterModel.setRequired(isRequired(parameter, actualParamType));

    if (actualParamType != parameter.getParameterizedType())
        parameterModel.setRequired(false);

    return parameterModel;
}
 

@Override
protected Class<?> buildRequestClass(final Class<?> clz, final Method method, final Naming naming) throws Exception {
    //ClassPool：CtClass对象的容器
    ClassPool pool = ClassPool.getDefault();
    //通过ClassPool生成一个public新类
    CtClass ctClass = pool.makeClass(naming.getFullName());
    ctClass.setInterfaces(new CtClass[]{pool.getCtClass(Serializable.class.getName()), pool.getCtClass(MethodArgs.class.getName())});
    //添加字段
    CtField ctField;
    String name;
    String typeName;
    Type type;
    int i = 0;
    StringBuilder toArgs = new StringBuilder(100).append("public Object[] toArgs(){\n\treturn new Object[]{");
    StringBuilder toFields = new StringBuilder(200).append("public void toFields(Object[] args){\n");
    for (Parameter parameter : method.getParameters()) {
        name = parameter.getName();
        type = parameter.getParameterizedType();
        typeName = type.getTypeName();
        ctField = new CtField(pool.getCtClass(typeName), name, ctClass);
        ctField.setModifiers(Modifier.PRIVATE);
        ctClass.addField(ctField);
        if (i > 0) {
            toArgs.append(',');
        }
        toArgs.append(name);
        toFields.append('\t').append(name).append("=(").append(typeName).append(")args[").append(i).append("];\n");
        name = name.substring(0, 1).toUpperCase() + name.substring(1);
        ctClass.addMethod(CtNewMethod.getter((boolean.class == type ? "is" : "get") + name, ctField));
        ctClass.addMethod(CtNewMethod.setter("set" + name, ctField));
        i++;
    }
    toArgs.append("};\n};");
    toFields.append("};");
    ctClass.addMethod(CtMethod.make(toArgs.toString(), ctClass));
    ctClass.addMethod(CtMethod.make(toFields.toString(), ctClass));
    return ctClass.toClass();
}
 

public ParameterizedType getParameterizedType() {
    for (Parameter p : method.getParameters()) {
        if (p.getName().equals(name) || String.format("arg%d", index).equals(p.getName())) {
            if (p.getParameterizedType() instanceof ParameterizedType) {
                return (ParameterizedType) p.getParameterizedType();
            }
        }
    }
    return null;
}
 

static <T> InjectionPoint<T> of(Parameter p)
{
  return new InjectionPointImpl<>((Key<T>) Key.of(p),
      p.getParameterizedType(),
      p.getName(),
      p.getAnnotations(),
      p.getDeclaringExecutable().getDeclaringClass());
}
 

protected Class<?> findListFormGenericType(Parameter parameter) {
    if (isListTypeParameter(parameter)) {
        final Type pt = parameter.getParameterizedType();
        final Class<?> genericType = DfReflectionUtil.getGenericFirstClass(pt); // almost not null, already checked
        return genericType != null && isBeanActionFormType(genericType) ? genericType : null; // e.g. List<SeaForm>
    }
    return null;
}
 

public static TypePair of(Parameter parameter) {
return new TypePair(parameter.getParameterizedType(), parameter.getType());        }
 

public static Type getGenericParameterType(Class<?> mainClass, Method method, Parameter param) {
  Type type = param.getParameterizedType();
  return getGenericParameterType(mainClass, method.getDeclaringClass(), type);
}
 

public Param(final Parameter parameter) {
    this(parameter.getParameterizedType(), parameter.getAnnotations(), parameter.getName());
}
 

private static void methodToString(StringBuilder sb,
                                   Method method,
                                   boolean isUseReturnType)
{
  if (isUseReturnType) {
    TypeVariable []typeVars = method.getTypeParameters();

    if (typeVars.length > 0) {
      sb.append("<");

      for (int i = 0; i < typeVars.length; i++) {
        if (i != 0) {
          sb.append(",");
        }

        sb.append(typeVars[i]);
      }

      sb.append(">");
      sb.append(" ");
    }

    sb.append("void " + method.getName() + "(");
  }

  Parameter []parameters = method.getParameters();
  for (int i = 0; i < parameters.length; i++ ) {
    if (i > 0) {
      sb.append(", ");
    }

    Parameter param = parameters[i];

    if (isUseReturnType && param.getParameterizedType() != null) {
      typeToString(sb, param.getParameterizedType(), false);
    }
    else {
      typeToString(sb, param.getType(), false);
    }

    sb.append(" " + param.getName());
  }

  if (isUseReturnType) {
    Type returnType = method.getGenericReturnType();

    if (returnType != void.class) {
      if (parameters.length > 0) {
        sb.append(", ");
      }

      sb.append("Result<");
      typeToString(sb, returnType, true);
      sb.append("> __result");
    }
  }

  sb.append(")");
}
 

/**
 * Builds Key from parameter's parameterized type and and qualifying annotations
 * found on the parameter and its declaring executable (e.g. Method)
 *
 * @param parameter parameter for deriving type and annotations from
 * @return instance of a key
 */
public static Key<?> of(Parameter parameter)
{
  return new Key(parameter.getParameterizedType(),
                 qualifiers(parameter.getAnnotations(),
                            parameter.getDeclaringExecutable().getAnnotations()));
}