我已经彻底浏览了杰克逊，似乎没有办法做到这一点。但是，我将在这里分享我的解决方案，以防它对其他人有用。
package com.example.config;
import com.example.dto.Example;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.springframework.http.HttpInputMessage;
import org.springframework.http.HttpOutputMessage;
import org.springframework.http.MediaType;
import org.springframework.http.converter.AbstractHttpMessageConverter;
import org.springframework.http.converter.HttpMessageNotReadableException;
import org.springframework.http.converter.HttpMessageNotWritableException;
import org.springframework.http.converter.StringHttpMessageConverter;
import org.w3c.dom.Node;
import org.xml.sax.InputSource;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import java.io.IOException;
import java.io.Reader;
import java.io.StringReader;
public class Converter extends AbstractHttpMessageConverter<Example> {
private static final XPath XPATH_INSTANCE = XPathFactory.newInstance().newXPath();
private static final StringHttpMessageConverter MESSAGE_CONVERTER = new StringHttpMessageConverter();
@Override
protected boolean supports(Class<?> aClass) {
return aClass == Example.class;
}
@Override
protected Example readInternal(Class<? extends LongFormDTO> aClass, HttpInputMessage httpInputMessage) throws IOException, HttpMessageNotReadableException {
String responseString = MESSAGE_CONVERTER.read(String.class, httpInputMessage);
Reader xmlInput = new StringReader(responseString);
InputSource inputSource = new InputSource(xmlInput);
Example dto = new Example();
Node xml;
try {
xml = (Node) XPATH_INSTANCE.evaluate("/properties", inputSource, XPathConstants.NODE);
} catch (XPathExpressionException e) {
log.error("Unable to parse response", e);
return dto;
}
log.info("processing populate application response={}", responseString);
dto.setToken(getString("token", xml));
dto.setAffid(getInt("affid", xml, 36));
dto.domain(getString("domain", xml));
xmlInput.close();
return dto;
}
private String getString(String propName, Node xml, String defaultValue) {
String xpath = String.format("//entry[@key='%s']/text()", propName);
try {
String value = (String) XPATH_INSTANCE.evaluate(xpath, xml, XPathConstants.STRING);
return StringUtils.isEmpty(value) ? defaultValue : value;
} catch (XPathExpressionException e) {
log.error("Received error retrieving property={} from xml", propName, e);
}
return defaultValue;
}
private String getString(String propName, Node xml) {
return getString(propName, xml, null);
}
private int getInt(String propName, Node xml, int defaultValue) {
String stringValue = getString(propName, xml);
if (!StringUtils.isEmpty(stringValue)) {
try {
return Integer.parseInt(stringValue);
} catch (NumberFormatException e) {
log.error("Attempted to parse value={} as integer but received error", stringValue, e);
}
}
return defaultValue;
}
private int getInt(String propName, Node xml) {
return getInt(propName, xml,0);
}
private boolean getBoolean(String propName, Node xml) {
String stringValue = getString(propName, xml );
return Boolean.valueOf(stringValue);
}
@Override
protected void writeInternal(Example dto, HttpOutputMessage httpOutputMessage) throws IOException, HttpMessageNotWritableException {
throw new UnsupportedOperationException("Responses of type=" + MediaType.TEXT_PLAIN_VALUE + " are not supported");
}
}
我选择将其隐藏在消息转换器中，因此我不必再次查看它，但您可以在您认为合适的地方应用这些步骤。如果你选择这个路由，你需要配置一个rest模板来使用这个转换器。如果不是，则将 xml 缓存到 Node 对象中很重要，因为每次重新生成都会非常昂贵。
package com.example.config;
import org.springframework.boot.web.client.RestTemplateBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.http.MediaType;
import org.springframework.http.client.OkHttp3ClientHttpRequestFactory;
import org.springframework.web.client.RestTemplate;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
@Configuration
public class RestConfig {
@Bean
@Primary
public RestTemplate restTemplate() {
return new RestTemplate(new OkHttp3ClientHttpRequestFactory());
}
@Bean
public RestTemplate restTemplateLe(RestTemplateBuilder builder) {
List<HttpMessageConverter<?>> messageConverters = new ArrayList<>();
ExampleConverter exampleConverter = new ExampleConverter();
exampleConverter.setSupportedMediaTypes(Collections.singletonList(MediaType.TEXT_PLAIN));
messageConverters.add(exampleConverter);
return builder.messageConverters(messageConverters)
.requestFactory(new OkHttp3ClientHttpRequestFactory())
.build();
}
}