java - 如何在 Jackson xml 解析器中将八位字节流解析为 json？

Question

我有时会收到设置了 content-type=application/octet-stream 的 Web 服务响应，无论如何它实际上是 application/xml。

由于我无法控制 Web 服务，因此我仍然想告诉 jackson(我正在与 spring-boot 一起使用)将这些响应解析为 xml。但如何呢？

我首先尝试为 jackson 映射器允许八位字节流，到目前为止它有效:

@Bean
public RestTemplateCustomizer customizeJackson2MessageConverter() {
    return restTemplate -> {
        for (var converter : restTemplate.getMessageConverters()) {
            if (converter instanceof MappingJackson2HttpMessageConverter) { 
                jackson.getSupportedMediaTypes().add((MediaType.APPLICATION_OCTET_STREAM);
            }
        }
    };
}

但是:当涉及到解析时，我如何告诉 Jackson 忽略/重写内容类型，并仍然将其解析为正常的 json？

Caused by: org.springframework.http.converter.HttpMessageNotReadableException: JSON parse error: Unexpected character ('<' (code 60)): expected a valid value (number, String, array, object, 'true', 'false' or 'null'); nested exception is com.fasterxml.jackson.core.JsonParseException: Unexpected character ('<' (code 60)): expected a valid value (number, String, array, object, 'true', 'false' or 'null')
 at [Source: (ByteArrayInputStream); line: 1, column: 2]
    at org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.readJavaType(AbstractJackson2HttpMessageConverter.java:245) ~[spring-web-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.read(AbstractJackson2HttpMessageConverter.java:227) ~[spring-web-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.web.client.HttpMessageConverterExtractor.extractData(HttpMessageConverterExtractor.java:102) ~[spring-web-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    ... 113 more

Answer 1

我按照@chrylis的建议做了:

public class ContentTypeInterceptor implements ClientHttpRequestInterceptor {
    @Override
    public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {
        ClientHttpResponse http = execution.execute(request, body);

        HttpHeaders headers = http.getHeaders();
        if (headers.getContentType() == MediaType.APPLICATION_OCTET_STREAM) {
            headers.setContentType(MediaType.APPLICATION_XML);
        }

        return http;
    }
}