Liquid XML Studio is a FREE XML Schema Editor, and much more.
Simple enough for new users to pick up quickly and comprehensive enough for experienced users deal with the advanced features of the XSD standard.
KG: Free, but not open source. For the quick schema edit...
Cogenit's Xcarecrows 4 XML for Eclipse completes today's powerful integrated development environment to handle the daily tasks required by an XML workflow. To this end, Xcarecrows 4 XML offers:
* a graphical XML, XML Schema and XML stylesheets editor ;
* a graphical XML tree comparator ;
* a built-in checker against XML Schemas ;
* an XSL transformations tool kit.
When the only thing you've got is a XML Hammer, every solution looks like XML.
The XML Hammer application is a free and open-source tool that simplifies elementary XML actions like checking for well-formedness, validation, transformation and xpath searches using any JAXP implementation.
After all these years of XML, it is still relatively difficult to simply validate or transform XML files. You are currently either forced to use extensive, sometimes expensive, and most often difficult to use tools with a lot of extra functionality unnecessary for these simple tasks and very often not flexible enough to provide what you want, or you will have to be almost a programmer and create your own application or script to handle these elementary XML related tasks.
The XML Hammer tool addresses these issues by providing a free and open-source tool that has a (relatively) simple to use user-interface however still allowing the flexibility for the user to specify anything that he/she would have been able to specify when writing a script for this same task him/herself.
The functionality of the XML Hammer tool is based on the capabilities provided by the Java API for XML Processing (JAXP) and supports the JAXP API as fully as possible. To achieve this, the functionality has been divided into five specific project types:
Pedro is an application that creates data entry forms based on a data model written in a particular style of XML Schema. Users can enter data through the forms to create data files that conform to the schema. They can use controlled vocabularies to mark-up text fields and have the application perform basic validation on field data. When they feel they have finished writing a data file, Pedro can tell them if they have left out any required records.
W3C Schema can quickly become complex and difficult to determine if they are validating the correct vocabulary. The addition of embedded Schematron schema only makes this problem worse. Schema Unit Test (SUT) introduces a framework for testing XML Schema.
This framework has two parts.
The first is a namespace and vocabulary for embedding test cases into sample XML documents, designed to highlight what is legal and what is not legal in the vocabulary defined in the schema under test. This aspect is independent of what schema language is used and can in theory be applied to any schema language with automatic validation tools.
The second part is a Java implementation using JUnit for testing a W3C Schema with embedded Schematron schema. This implementation reads SUT test suite descriptions written in XML with embedded test cases as described above and then creates a JUnit test suite that can be executed inside JUnit in the usual way.
xsdeclipse provides an eclipse user interface for xsdTransformer xsdTransformer. xsdTransformer transforms XML schemata to other code (e.g. xhml sites containing XForms forms, JavaServer Pages containing jsf forms et al.). The provided xsdeclipse downloads are completely installable and runnable as it is. For only using xsdeclipse you don't need to download xsdTransformer.
G. Bex, F. Neven, and J. Van den Bussche. WebDB '04: Proceedings of the 7th International Workshop on the Web and Databases, page 79--84. New York, NY, USA, ACM Press, (2004)