Jackson is "the Java JSON library" or "the best JSON parser for Java". Or simply as "JSON for Java".

Jackson also allows you to parse or generate XML messages with the Jackson Dataformat XML Extension.

Jackson Dataformat XML Source Code files are provided in the source packge (jackson-dataformat-xml-2.14.0-sources.jar). You can download it at Jackson Maven Website.

You can also browse Jackson Dataformat XML Source Code below:

⏎ com/fasterxml/jackson/dataformat/xml/JacksonXmlModule.java

package com.fasterxml.jackson.dataformat.xml;

import com.fasterxml.jackson.databind.AnnotationIntrospector;
import com.fasterxml.jackson.databind.module.SimpleModule;

import com.fasterxml.jackson.dataformat.xml.deser.FromXmlParser;
import com.fasterxml.jackson.dataformat.xml.deser.XmlBeanDeserializerModifier;
import com.fasterxml.jackson.dataformat.xml.ser.XmlBeanSerializerModifier;

/**
 * Module that implements most functionality needed to support producing and
 * consuming XML instead of JSON, used by {@link XmlMapper} for registering
 * handlers for XML-specific processing.
 *<p>
 * NOTE: please do NOT register this directly on {@link XmlMapper}: mapper
 * registers an instance (either one explicitly given in constructor, or, if none,
 * one it configures) and attempts to re-register is unlikely to work as
 * you'd expect.
 */
public class JacksonXmlModule
    extends SimpleModule
    implements java.io.Serializable
{
    private static final long serialVersionUID = 1L;

    /**
     * Determination of whether indexed properties (arrays, Lists) that are not explicitly
     * annotated (with {@link com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlElementWrapper}
     * or equivalent) should default to using implicit wrapper (with same name as property) or not.
     * If enabled, wrapping is used by default; if false, it is not.
     *<p>
     * Note that JAXB annotation introspector always assumes "do not wrap by default".
     * Jackson annotations have different default due to backwards compatibility.
     * 
     * @since 2.1
     */
    protected boolean _cfgDefaultUseWrapper = JacksonXmlAnnotationIntrospector.DEFAULT_USE_WRAPPER;

    /**
     * Name used for pseudo-property used for returning XML Text value (which does
     * not have actual element name to use). Defaults to empty String, but
     * may be changed for interoperability reasons: JAXB, for example, uses
     * "value" as name.
     * 
     * @since 2.1
     */
    protected String _cfgNameForTextElement = FromXmlParser.DEFAULT_UNNAMED_TEXT_PROPERTY;
    
    /*
    /**********************************************************************
    /* Life-cycle: construction
    /**********************************************************************
     */
    
    public JacksonXmlModule()
    {
        super("JacksonXmlModule", PackageVersion.VERSION);
    }

    @SuppressWarnings("deprecation")
    @Override
    public void setupModule(SetupContext context)
    {
        // Need to modify BeanDeserializer, BeanSerializer that are used
        context.addBeanSerializerModifier(new XmlBeanSerializerModifier());
        context.addBeanDeserializerModifier(new XmlBeanDeserializerModifier(_cfgNameForTextElement));

        // as well as AnnotationIntrospector
        context.insertAnnotationIntrospector(_constructIntrospector());

        // and finally inform XmlFactory about overrides, if need be:
        if (_cfgNameForTextElement != FromXmlParser.DEFAULT_UNNAMED_TEXT_PROPERTY) {
            XmlMapper m = (XmlMapper) context.getOwner();
            m.setXMLTextElementName(_cfgNameForTextElement);
        }

        // Usually this would be the first call; but here anything added will
        // be stuff user may has added, so do it afterwards instead.
        super.setupModule(context);
    }    

    /*
    /**********************************************************************
    /* Life-cycle: configuration
    /**********************************************************************
     */

    /**
     * Method that can be used to define whether {@link AnnotationIntrospector}
     * we register will use wrapper for indexed (List, array) properties or not,
     * if there are no explicit annotations.
     * See {@link com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlElementWrapper}
     * for details.
     *<p>
     * Note that method MUST be called before registering the module; otherwise change
     * will not have any effect.
     * 
     * @param state Whether to enable or disable "use wrapper for non-annotated List properties"
     * 
     * @since 2.1
     */
    public void setDefaultUseWrapper(boolean state) {
        _cfgDefaultUseWrapper = state;
    }

    /**
     * Method that can be used to define alternate "virtual name" to use
     * for XML CDATA segments; that is, text values. Default name is empty String
     * (""); but some frameworks use other names: JAXB, for example, uses
     * "value".
     *<p>
     * Note that method MUST be called before registering the module; otherwise change
     * will not have any effect.
     * 
     * @param name Virtual name to use when exposing XML character data sections
     * 
     * @since 2.1
     */
    public void setXMLTextElementName(String name) {
        _cfgNameForTextElement = name;
    }
    
    /*
    /**********************************************************************
    /* Internal methods
    /**********************************************************************
     */

    protected AnnotationIntrospector _constructIntrospector() {
        return new JacksonXmlAnnotationIntrospector(_cfgDefaultUseWrapper);
    }
}

⏎ com/fasterxml/jackson/dataformat/xml/JacksonXmlModule.java

Or download all of them as a single archive file:

File name: jackson-dataformat-xml-2.14.0-sources.jar
File size: 98015 bytes
Release date: 2022-11-05
Download 

⇒ Download Jackson Dataformat Binary Packages

⇐ Jackson Dataformat Extensions

⇑ Downloading and Reviewing jackson-*.jar

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