XMLValidate Task

## XMLValidate

### Description

This task checks that XML files are valid (or only well formed). The task uses the SAX2 parser implementation provided by JAXP by default (probably the one that is used by Apache Ant itself), but one can specify any SAX1/2 parser if needed.

This task supports the use of nested

- `<xmlcatalog>` elements
- `<dtd>` elements which are used to resolve DTDs and entities
- `<attribute>` elements which are used to set features on the parser. These can be any number of `http://xml.org/sax/features/` or other features that your parser may support.
- `<property>` elements, containing string properties

  Warning : JAXP creates by default a non namespace aware parser. The `"http://xml.org/sax/features/namespaces"` feature is set by default to `false` by the JAXP implementation used by ant. To validate a document containing namespaces, set the namespaces feature to `true` explicitly by nesting the following element:

        <attribute name="http://xml.org/sax/features/namespaces" value="true"/>

  If you are using for instance a `xsi:noNamespaceSchemaLocation` attribute in your XML files, you will need this namespace support feature.

  If you are using a parser not generated by JAXP, by using the `classname` attribute of xmlvalidate, this warning may not apply.

  ### Parameters

  Attribute | Description | Required
  file | the file(s) you want to check. (optionally can use an embedded fileset) | No
  lenient | if true, only check the XML document is well formed (ignored if the specified parser is a SAX1 parser) | No
  classname | the parser to use. | No
  classpathref | where to find the parser class. Optionally can use an embedded `<classpath>` element. | No
  failonerror | fails on a error if set to true (defaults to true). | No
  warn | log parser warn events. | No

  ### Nested Elements

  #### dtd

  `<dtd>` is used to specify different locations for DTD resolution.

  Attribute | Description | Required
  publicId | Public ID of the DTD to resolve | Yes
  location | Location of the DTD to use, which can be a file, a resource, or a URL | Yes

  #### xmlcatalog

  The `<xmlcatalog>` element is used to perform entity resolution.

  #### attribute

  The `<attribute>` element is used to set parser features.
  Features usable with the xerces parser are defined here : Setting features
  SAX features are defined here: `http://xml.org/sax/features/`

  Attribute | Description | Required
  name | The name of the feature | Yes
  value | The boolean value of the feature | Yes

  #### property

  The `<property>` element is used to set properties. These properties are defined here for the xerces XML parser implementation : XML Parser properties Properties can be used to set the schema used to validate the XML file.

  Attribute | Description | Required
  name | The name of the feature | Yes
  value | The string value of the property | Yes

  ### Examples

      <xmlvalidate file="toto.xml"/>

  Validate toto.xml

      <xmlvalidate failonerror="no" lenient="yes" warn="yes"
                   classname="org.apache.xerces.parsers.SAXParser">
                   classpath="lib/xerces.jar">
        <fileset dir="src" includes="style/*.xsl"/>
      </xmlvalidate>

  Validate all .xsl files in src/style, but only warn if there is an error, rather than halt the build.

      <xmlvalidate file="struts-config.xml" warn="false">
        <dtd publicId="-//Apache Software Foundation//DTD Struts Configuration 1.0//EN"
             location="struts-config_1_0.dtd"/>
      </xmlvalidate>

  Validate a struts configuration, using a local copy of the DTD.

      <xmlvalidate failonerror="no">
        <fileset dir="${project.dir}" includes="**/*.xml"/>
        <xmlcatalog refid="mycatalog"/>
      </xmlvalidate>

  Scan all XML files in the project, using a predefined catalog to map URIs to local files.

      <xmlvalidate failonerror="no">
        <fileset dir="${project.dir}" includes="**/*.xml"/>
        <xmlcatalog>
             <dtd
               publicId="-//ArielPartners//DTD XML Article V1.0//EN"
               location="com/arielpartners/knowledgebase/dtd/article.dtd"/>
        </xmlcatalog>
      </xmlvalidate>

  Scan all XML files in the project, using the catalog defined inline.

      <xmlvalidate failonerror="yes" lenient="no" warn="yes">
        <fileset dir="xml" includes="**/*.xml"/>
        <attribute name="http://xml.org/sax/features/validation" value="true"/>
        <attribute name="http://apache.org/xml/features/validation/schema"  value="true"/>
        <attribute name="http://xml.org/sax/features/namespaces" value="true"/>
      </xmlvalidate>

  Validate all .xml files in xml directory with the parser configured to perform XSD validation. Note: The parser must support the feature `http://apache.org/xml/features/validation/schema`. The schemavalidate task is better for validating W3C XML Schemas, as it extends this task with the right options automatically enabled, and makes it easy to add a list of schema files/URLs to act as sources.

      <pathconvert dirsep="/" property="xsd.file">
      <path>
         <pathelement location="xml/doc.xsd"/>
      </path>
      </pathconvert>

      <xmlvalidate file="xml/endpiece-noSchema.xml" lenient="false"
        failonerror="true" warn="true">
        <attribute name="http://apache.org/xml/features/validation/schema"
        value="true"/>
        <attribute name="http://xml.org/sax/features/namespaces" value="true"/>
        <property
        name="http://apache.org/xml/properties/schema/external-noNamespaceSchemaLocation"
        value="${xsd.file}"/>
      </xmlvalidate>

  Validate the file xml/endpiece-noSchema.xml against the schema xml/doc.xsd.