XStream

Last updated
XStream Library
Developer(s) Codehaus
Initial releaseJanuary 1, 2004;19 years ago (2004-01-01)
Stable release
1.4.20 / December 24, 2022;12 months ago (2022-12-24)
Written in Java
Operating system Cross-platform
License BSD-style license
Website x-stream.github.io

XStream is a Java library to serialize objects to XML (or JSON) and back again.

Contents

XStream library

XStream uses reflection to discover the structure of the object graph to serialize at run time, and doesn't require modifications to objects. It can serialize internal fields, including private and final, and supports non-public and inner classes. [1]

Object graph serialization

When serializing an object it serializes the full object graph. Duplicate references encountered in the object-model will be maintained. For example, using the following class CD

packagecom.thoughtworks.xstream;publicclassCd{privateStringid;privateCdbonusCd;Cd(Stringid,CdbonusCd){this.id=id;this.bonusCd=bonusCd;}Cd(Stringid){this.id=id;}publicStringgetId(){returnid;}publicCdgetBonusCd(){returnbonusCd;}}

and add some of these object to a list

Cdbj=newCd("basement_jaxx_singles");Cdmr=newCd("maria rita");List<Cd>order=newArrayList<>();order.add(mr);// adds the same cd twice (two references to the same object)order.add(bj);order.add(bj);// adds itself (cycle)order.add(order);XStreamxstream=newXStream();xstream.alias("cd",Cd.class);System.out.println(xstream.toXML(order));

If the above code is executed with XStream's default relative references mode, it will generate the following XML:

<list><cd><id>mariarita</id></cd><cd><id>basement_jaxx_singles</id></cd><cdreference="../cd[2]"/><listreference=".."/></list>

XStream is free software, distributed under a permissive, revised BSD-style licence.

Usage

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References

  1. "Use XStream to serialize Java objects into XML". Ibm.com. Archived from the original on February 19, 2009. Retrieved 2009-12-14.
  2. "XStream - References". Xstream.codehaus.org. Retrieved 2009-12-14.