Question

我想在AnnotationMethodHandlerAdapter中自定义下面的方法，该方法用于在spring中映射带注释的方法。

public static boolean checkHeaders（String [] headers，HttpServletRequest request）{}

如何在spring中配置我的适配器，我已经覆盖了checkHeaders方法。

Answer 1

<mvc:annotation-driven />标记的作用通常是在应用程序上下文中自动注册AnnotationMethodHandlerAdapter和关联的bean。

如果要手动注册自己的自定义AnnotationMethodHandlerAdapter子类，则应删除<mvc:annotation-driven />标记并在dispatcher-servlet.xml中声明自定义bean。

<bean class="some.package.MyCustomAnnotationMethodHandlerAdapter">
    <property name="someProperty" value="someValue"/>
</bean>

如果您不删除<mvc:annotation-driven/>，那么您将在应用程序上下文中获得两个AnnotationMethodHandlerAdapter bean - 而您的自定义bean将被忽略。

有一篇非常好的帖子here讨论了如何自定义AnnotationMethodHandlerAdapter并使用BeanPostProcessor来修改默认AnnotationMethodHandlerAdapter的替代方法。< / p>

值得指出的是，{3.2}在Spring 3.2中被弃用，而不是AnnotationMethodHandlerAdapter

Answer 2

我遇到了与Will描述的相同的麻烦，并且解决了问题，这是恕我直言，比文章here中提出的更简单，更紧凑：

@Component（ “customHttpMessageConverter”）公共类DemoHttpMessageConverter扩展MappingJacksonHttpMessageConverter {

@Autowired
AnnotationMethodHandlerAdapter handlerAdapter; // <-- will be injected by Spring

@PostConstruct
public void init() {
    // here the field 'handlerAdapter' is already injected
    // and you can either extend or substitute the list of message-converters
    handlerAdapter.setMessageConverters(new HttpMessageConverter[] {this});
}

@Override
public boolean canRead(Class<?> clazz, MediaType mediaType) {
    // we use JAXB in our project, but you can provide your own logic here
    // or just return 'true' if you are sure that @ResponseBody and @RequestBody are used properly      
    return clazz.isAnnotationPresent(XmlRootElement.class);
}

@Override
public boolean canWrite(Class<?> clazz, MediaType mediaType) {
    // ... the same as with 'canRead' ...
    return clazz.isAnnotationPresent(XmlRootElement.class);
}

@Override
protected Object readInternal(Class<?> clazz, HttpInputMessage inputMessage) throws IOException, HttpMessageNotReadableException {
    String inputMessageStr = IOUtils.toString(inputMessage.getBody());
    return customDeserialize(inputMessageStr);
}

@Override
protected void writeInternal(Object obj, HttpOutputMessage outputMessage) throws IOException, HttpMessageNotWritableException {
    String outputMessageStr = customSerialize(inputMessageStr);
    IOUtils.write(outputMessageStr, outputMessage.getBody(), JsonEncoding.UTF8.getJavaName());
}

public Object customDeserialize(String json) {
    // your own de-serialization 
}

public String customSerialize(Object obj) {
    // your own serialization 
}

}

AnnotationMethodHandlerAdapter的自定义实现

2 个答案: