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The XStream library offers clean, easy XML serialization of POJOs.

XStream serializes and restores very clean, readable XML from POJOs, like this:

public class Publisher {
	private String publisherID;
	private String name;
    // getters and setters...
    }
    
    Becomes:

<Publisher> 

    <publisherID>lorenz</publisherID> 

    <name>Lorenz Corporation</name> 

</Publisher> 

Using two lines of code (although you can customize lots of things if needed.)

XStream xstream = new XStream();
String xml = xstream.toXML(obj);

If you don't want it to include the fully qualified class name:

<com.choralmusic.db.Publisher>

Add one line:

xstream.alias("Publisher", Publisher.class);

Collections look great, for example, this ArrayList of Listing objects:

    <listings>
      <Listing>
        <pageRef>church_christmas</pageRef>
        <includeCover>false</includeCover>
      </Listing>
      <Listing>
        <pageRef>school_winter</pageRef>
        <includeCover>false</includeCover>
      </Listing>
    </listings>

Restoring the object is two lines (with optional aliases):

XStream xstream = new XStream();
// If you don't have fully qualified names, add one or more aliases:
xstream.alias("CatalogItem", CatalogItem.class);
catalogItems = (ArrayList) xstream.fromXML(theXMLString);

The XML suitable for editing by hand for configuration or if persisted to a file. It would be very easy to manipulate via XSLT or XQUERY. It makes a nice readable toString() for debugging.

License: BSD derived, commercial friendly.

Dependencies: none (!), XML Pull Parser optional to improve performance.

Limitations

When using the Sun 1.4 (and 1.5) JVM, XStream can reinstantiate classes that do not have a default constructor. (Cool rule-breaking magic.) Other JVMs require a default constructor.

Check out XStream and the two minute tutorial.

XStream has worked very well for me. Thanks to Malcolm Davis for pointing out this terrific library.

This work is licensed under a Creative Commons License.