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/JacksonXmlAnnotationIntrospector.java

package com.fasterxml.jackson.dataformat.xml;

import java.lang.annotation.Annotation;

import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.PropertyName;
import com.fasterxml.jackson.databind.cfg.MapperConfig;
import com.fasterxml.jackson.databind.introspect.*;
import com.fasterxml.jackson.databind.jsontype.impl.StdTypeResolverBuilder;
import com.fasterxml.jackson.dataformat.xml.annotation.*;

/**
 * Extension of {@link JacksonAnnotationIntrospector} that is needed to support
 * additional xml-specific annotation that Jackson provides. Note, however, that
 * there is no JAXB annotation support here; that is provided with
 * separate introspector (see
 * https://github.com/FasterXML/jackson-modules-base/tree/master/jaxb,
 * class {@code com.fasterxml.jackson.module.jaxb.JaxbAnnotationIntrospector}).
 */
public class JacksonXmlAnnotationIntrospector
    extends JacksonAnnotationIntrospector
    implements XmlAnnotationIntrospector
{
    private static final long serialVersionUID = 1L;

    // @since 2.11.1
    @SuppressWarnings("unchecked")
    private final static Class<? extends Annotation>[] ANNOTATIONS_TO_INFER_XML_PROP =
            (Class<? extends Annotation>[]) new Class<?>[] {
        JacksonXmlText.class, JacksonXmlElementWrapper.class
    };

    /**
     * For backwards compatibility with 2.0, the default behavior is
     * to assume use of List wrapper if no annotations are used.
     */
    public final static boolean DEFAULT_USE_WRAPPER = true;

    // non-final from 2.7 on, to allow mapper to change
    protected boolean _cfgDefaultUseWrapper;

    public JacksonXmlAnnotationIntrospector() {
        this(DEFAULT_USE_WRAPPER);
    }

    public JacksonXmlAnnotationIntrospector(boolean defaultUseWrapper) {
        _cfgDefaultUseWrapper = defaultUseWrapper;
    }

    /*
    /**********************************************************************
    /* Extended API XML format module requires
    /**********************************************************************
     */

    public void setDefaultUseWrapper(boolean b) {
        _cfgDefaultUseWrapper = b;
    }

    /*
    /**********************************************************************
    /* Overrides of JacksonAnnotationIntrospector impls
    /**********************************************************************
     */

    @Override
    public PropertyName findWrapperName(Annotated ann)
    {
        JacksonXmlElementWrapper w = _findAnnotation(ann, JacksonXmlElementWrapper.class);
        if (w != null) {
            // Special case: wrapping explicitly blocked?
            if (!w.useWrapping()) {
                return PropertyName.NO_NAME;
            }
            // also: need to ensure we use marker:
            String localName = w.localName();
            if (localName == null || localName.length() == 0) {
                return PropertyName.USE_DEFAULT;
            }
            return PropertyName.construct(w.localName(), w.namespace());
        }
        // 09-Sep-2012, tatu: In absence of configuration we need to use our
        //   default settings...
        if (_cfgDefaultUseWrapper) {
            return PropertyName.USE_DEFAULT;
        }
        return null;
    }
    
    @Override
    public PropertyName findRootName(AnnotatedClass ac)
    {
        JacksonXmlRootElement root = _findAnnotation(ac, JacksonXmlRootElement.class);
        if (root != null) {
            String local = root.localName();
            String ns = root.namespace();
            
            if (local.length() == 0 && ns.length() == 0) {
                return PropertyName.USE_DEFAULT;
            }
            return new PropertyName(local, ns);
        }
        return super.findRootName(ac);
    }

    /*
    /**********************************************************************
    /* XmlAnnotationIntrospector, findXxx
    /**********************************************************************
     */

    @Override
    public String findNamespace(MapperConfig<?> config, Annotated ann)
    {
        JacksonXmlProperty prop = _findAnnotation(ann, JacksonXmlProperty.class);
        if (prop != null) {
            return prop.namespace();
        }
        // 14-Nov-2020, tatu: 2.12 adds namespace for this too
        JsonProperty jprop = _findAnnotation(ann, JsonProperty.class);
        if (jprop != null) {
            return jprop.namespace();
        }
        return null;
    }

    /*
    /**********************************************************************
    /* XmlAnnotationIntrospector, isXxx methods
    /**********************************************************************
     */

    @Override
    public Boolean isOutputAsAttribute(MapperConfig<?> config, Annotated ann)
    {
        JacksonXmlProperty prop = _findAnnotation(ann, JacksonXmlProperty.class);
        if (prop != null) {
            return prop.isAttribute() ? Boolean.TRUE : Boolean.FALSE;
        }
        return null;
    }
    
    @Override
    public Boolean isOutputAsText(MapperConfig<?> config, Annotated ann)
    {
        JacksonXmlText prop = _findAnnotation(ann, JacksonXmlText.class);
        if (prop != null) {
            return prop.value() ? Boolean.TRUE : Boolean.FALSE;
        }
        return null;
    }

    @Override
    public Boolean isOutputAsCData(MapperConfig<?> config, Annotated ann) {
        JacksonXmlCData prop = ann.getAnnotation(JacksonXmlCData.class);
        if (prop != null) {
            return prop.value() ? Boolean.TRUE : Boolean.FALSE;
        }
        return null;
    }

    /*
    /**********************************************************************
    /* Overrides for name, property detection
    /**********************************************************************
     */

    @Override
    public PropertyName findNameForSerialization(Annotated a)
    {
        PropertyName name = _findXmlName(a);
        if (name == null) {
            name = super.findNameForSerialization(a);
            if (name == null) {
                if (_hasOneOf(a, ANNOTATIONS_TO_INFER_XML_PROP)) {
                    return PropertyName.USE_DEFAULT;
                }
            }
        }
        return name;
    }

    @Override
    public PropertyName findNameForDeserialization(Annotated a)
    {
        PropertyName name = _findXmlName(a);
        if (name == null) {
            name = super.findNameForDeserialization(a);
            if (name == null) {
                if (_hasOneOf(a, ANNOTATIONS_TO_INFER_XML_PROP)) {
                    return PropertyName.USE_DEFAULT;
                }
            }
        }
        return name;
    }
    
    /*
    /**********************************************************************
    /* Overrides for non-public helper methods
    /**********************************************************************
     */

    /**
     * We will override this method so that we can return instance
     * that cleans up type id property name to be a valid xml name.
     */
    @Override
    protected StdTypeResolverBuilder _constructStdTypeResolverBuilder() {
        return new XmlTypeResolverBuilder();
    }

    /*
    /**********************************************************************
    /* Internal methods
    /**********************************************************************
     */

    protected PropertyName _findXmlName(Annotated a)
    {
        JacksonXmlProperty pann = _findAnnotation(a, JacksonXmlProperty.class);
        if (pann != null) {
            return PropertyName.construct(pann.localName(), pann.namespace());
        }
        return null;
    }
}

⏎ com/fasterxml/jackson/dataformat/xml/JacksonXmlAnnotationIntrospector.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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