自定义springfox swagger对spring Pageable的支持

1. 最近查看spring-data-jpa官方文档，发现pageable分页对象可以直接作为controller方法的参数。测试后发现在springfox swagger上展示太好，暴露接口的所有get方法作为了参数。
2. 尝试通过springfox swagger的扩展进行定制化，搜索后在stackoverflow发现一篇帖子有解决这个问题。最终修改后满足自己的需求。代码如下：

@Configuration
@SuppressWarnings("SpringJavaAutowiringInspection")
public class SpringDataPageConfiguration {

    @Bean
    public AlternateTypeRuleConvention pageableConvention(final SpringDataWebProperties webProperties) {
        return new AlternateTypeRuleConvention() {
            @Override
            public int getOrder() {
                return Ordered.LOWEST_PRECEDENCE;
            }

            @Override
            public List<AlternateTypeRule> rules() {
                return singletonList(
                        newRule(Pageable.class, pageableDocumentedType(webProperties.getPageable(), webProperties.getSort()))
                );
            }
        };
    }

    private Type pageableDocumentedType(SpringDataWebProperties.Pageable pageable, SpringDataWebProperties.Sort sort) {
        final String firstPage = pageable.isOneIndexedParameters() ? "1" : "0";
        return new AlternateTypeBuilder()
                .fullyQualifiedClassName(fullyQualifiedName(Pageable.class))
                .property(property(pageable.getPageParameter(), Integer.class, ImmutableMap.of(
                        "value", "页码，" + String.format("允许范围[%s, %s]", firstPage, Integer.MAX_VALUE),
                        "defaultValue", firstPage,
                        "allowableValues", String.format("range[%s, %s]", firstPage, Integer.MAX_VALUE),
                        "example", firstPage,
                        "required", true
                )))
                .property(property(pageable.getSizeParameter(), Integer.class, ImmutableMap.of(
                        "value", "每页大小，" + String.format("允许范围[1, %s]", pageable.getMaxPageSize()),
                        "defaultValue", String.valueOf(pageable.getDefaultPageSize()),
                        "allowableValues", String.format("range[1, %s]", pageable.getMaxPageSize()),
                        "example", "10",
                        "required", true
                )))
                .property(property(sort.getSortParameter(), String[].class, ImmutableMap.of(
                        "value", "页面排序,格式为: 字段名,(asc|desc),asc表升序，desc表降序"
                )))
                .build();
    }

    private String fullyQualifiedName(Class<?> convertedClass) {
        return String.format("%s.generated.%s", convertedClass.getPackage().getName(), convertedClass.getSimpleName());
    }


    private AlternateTypePropertyBuilder property(String name, Class<?> type, Map<String, Object> parameters) {
        return new AlternateTypePropertyBuilder()
                .withName(name)
                .withType(type)
                .withCanRead(true)
                .withCanWrite(true)
                .withAnnotations(singletonList(AnnotationProxy.of(ApiParam.class, parameters)));
    }

@AllArgsConstructor(access = AccessLevel.PRIVATE)
@Accessors(fluent = true)
public class AnnotationProxy implements Annotation, InvocationHandler {
    @Getter
    private final Class<? extends Annotation> annotationType;
    private final Map<String, Object> values;

    public static <A extends Annotation> A of(Class<A> annotation, Map<String, Object> values) {
        return (A) Proxy.newProxyInstance(annotation.getClassLoader(),
                new Class[]{annotation},
                new AnnotationProxy(annotation, new HashMap<>(values) {{
                    put("annotationType", annotation); // Required because getDefaultValue() returns null for this call
                }}));
    }

    @Override
    public Object invoke(Object proxy, Method method, Object[] args) {
        return values.getOrDefault(method.getName(), method.getDefaultValue());
    }
}

1. 页面展示效果如下：