java - 如何在 Spring Boot 应用程序中将 XML Prolog 插入到 Rest XML 响应

Question

如何在 Spring Boot 应用程序中将 XML Prolog 插入到 Rest XML 响应。

我在 Spring Boot Rest api 中使用 jackson xml 数据格式。

我当前的rest-xml响应是:

<Response>
     <person id = "hello">
        <name>xyz</name>
     </person>
</Response>

当我想要的时候:

<?xml version = "1.0" encoding = "UTF-8"?>
<Response>
     <person id = "hello">
        <name>xyz</name>
     </person>
</Response>

Answer 1

希望这会对某人有所帮助:为了获得完整的解决方案，请从 Sambit 获取答案，稍微调整一下并编写以下实用程序类。请注意，convertPojoToXmlString() 返回一个 XML 字符串，然后可以将其发送回调用者:

package com.xml.util;
import java.io.IOException;
import java.io.StringWriter;

import javax.xml.stream.FactoryConfigurationError;
import javax.xml.stream.XMLOutputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamWriter;

import com.ctc.wstx.api.WstxInputProperties;
import com.fasterxml.jackson.dataformat.xml.XmlMapper;

/**
 * @author ekariyev
 *
 */
public class XmlUtil {

    private final static XMLOutputFactory xmlOutputFactory = XMLOutputFactory.newFactory();

    static {
        xmlOutputFactory.setProperty(WstxInputProperties.P_RETURN_NULL_FOR_DEFAULT_NAMESPACE, true);
    }

    /**
     * @param object
     * @return
     * @throws XMLStreamException
     * @throws IOException
     * @throws FactoryConfigurationError
     */
    public static String convertPojoToXmlString(final Object object) throws XMLStreamException, IOException {

        final StringWriter stringWriter = new StringWriter();

        try {
            final XMLStreamWriter sw = xmlOutputFactory.createXMLStreamWriter(stringWriter);
            final XmlMapper mapper = new XmlMapper();

            sw.writeStartDocument();

            mapper.writeValue(sw, object);

            sw.writeEndDocument();

            sw.flush();

        } finally {
            stringWriter.close();
        }

        return stringWriter.toString();

    }

}

该解决方案适用于:

<dependency>
    <groupId>com.fasterxml.jackson.dataformat</groupId>
    <artifactId>jackson-dataformat-xml</artifactId>
    <version>2.9.5</version>
</dependency>