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/ser/XmlBeanSerializer.java

package com.fasterxml.jackson.dataformat.xml.ser;

import java.io.IOException;
import java.util.Set;

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import com.fasterxml.jackson.databind.ser.BeanPropertyWriter;
import com.fasterxml.jackson.databind.ser.BeanSerializer;
import com.fasterxml.jackson.databind.ser.impl.BeanAsArraySerializer;
import com.fasterxml.jackson.databind.ser.impl.ObjectIdWriter;
import com.fasterxml.jackson.databind.ser.std.BeanSerializerBase;
import com.fasterxml.jackson.databind.util.NameTransformer;

/**
 * Variant of {@link BeanSerializer} for XML handling.
 * 
 * @author Pascal Gélinas
 */
public class XmlBeanSerializer extends XmlBeanSerializerBase
{
    private static final long serialVersionUID = 1L;

    /*
    /**********************************************************
    /* Life-cycle: constructors
    /**********************************************************
     */
    public XmlBeanSerializer(BeanSerializerBase src) {
        super(src);
    }

    public XmlBeanSerializer(XmlBeanSerializerBase src, ObjectIdWriter objectIdWriter, Object filterId) {
        super(src, objectIdWriter, filterId);
    }

    public XmlBeanSerializer(XmlBeanSerializerBase src, ObjectIdWriter objectIdWriter) {
        super(src, objectIdWriter);
    }

    public XmlBeanSerializer(XmlBeanSerializerBase src, Set<String> toIgnore, Set<String> toInclude) {
        super(src, toIgnore, toInclude);
    }

    protected XmlBeanSerializer(XmlBeanSerializerBase src,
            BeanPropertyWriter[] properties, BeanPropertyWriter[] filteredProperties)
    {
        super(src, properties, filteredProperties);
    }

    /*
    /**********************************************************
    /* Life-cycle: factory methods, fluent factories
    /**********************************************************
     */

    @Override
    public JsonSerializer<Object> unwrappingSerializer(NameTransformer unwrapper) {
        return new UnwrappingXmlBeanSerializer(this, unwrapper);
    }
    
    @Override
    public BeanSerializerBase withObjectIdWriter(ObjectIdWriter objectIdWriter) {
        return new XmlBeanSerializer(this, objectIdWriter, _propertyFilterId);
    }

    @Override
    public BeanSerializerBase withFilterId(Object filterId) {
        return new XmlBeanSerializer(this, _objectIdWriter, filterId);
    }

    @Override // since 2.12
    protected BeanSerializerBase withByNameInclusion(Set<String> toIgnore, Set<String> toInclude) {
        return new XmlBeanSerializer(this, toIgnore, toInclude);
    }

    @Override // since 2.11.1
    protected BeanSerializerBase withProperties(BeanPropertyWriter[] properties,
            BeanPropertyWriter[] filteredProperties) {
        return new XmlBeanSerializer(this, properties, filteredProperties);
    }

    /**
     * Implementation has to check whether as-array serialization
     * is possible reliably; if (and only if) so, will construct
     * a {@link BeanAsArraySerializer}, otherwise will return this
     * serializer as is.
     */
    @Override
    protected BeanSerializerBase asArraySerializer()
    {
        /* Can not:
         * 
         * - have Object Id (may be allowed in future)
         * - have any getter
         */
        if ((_objectIdWriter == null)
                && (_anyGetterWriter == null)
                && (_propertyFilterId == null)
                ) {
            return new BeanAsArraySerializer(this);
        }
        // already is one, so:
        return this;
    }

    /*
    /**********************************************************
    /* JsonSerializer implementation that differs between impls
    /**********************************************************
     */

    /**
     * Main serialization method that will delegate actual output to configured
     * {@link BeanPropertyWriter} instances.
     */
    @Override
    public void serialize(Object bean, JsonGenerator g, SerializerProvider provider) throws IOException
    {
        if (_objectIdWriter != null) {
            _serializeWithObjectId(bean, g, provider, true);
            return;
        }
        g.writeStartObject();
        if (_propertyFilterId != null) {
            serializeFieldsFiltered(bean, g, provider);
        } else {
            serializeFields(bean, g, provider);
        }
        g.writeEndObject();
    }

    /*
    /**********************************************************
    /* Standard methods
    /**********************************************************
     */

    @Override
    public String toString() {
        return "XmlBeanSerializer for " + handledType().getName();
    }
}

⏎ com/fasterxml/jackson/dataformat/xml/ser/XmlBeanSerializer.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

⇑⇑ Jackson - Java JSON library