XmlProperty Task

## XmlProperty

### Description

Loads property values from a well-formed xml file. There are no other restrictions than "well-formed". You can choose the layout you want. For example this XML property file:

      <root>
        <properties>
          <foo>bar</foo>
        </properties>
      </root>

is roughly equivalent to this Java property file:

      root.properties.foo = bar

By default, this load does no processing of the input. In particular, unlike the Property task, property references (i.e., `${foo}`) are not resolved.

### Semantic Attributes

Input processing can be enabled by using the semanticAttributes attribute. If this attribute is set to true (its default is false), the following processing occurs as the input XML file is loaded:

- Property references are resolved.
- The following attributes are treated differently:
  - id: The property is associated with the given id value.
  - location: The property is treated as a file location
  - refid: The property is set to the value of the referenced property.
  - value: The property is set to the value indicated.
- Path-like Structures can be defined by use of the following attributes:
  - pathid: The given id is used to identify a path. The nested XML tag name is ignored. Child elements can be used (XML tag names are ignored) to identify elements of the path.

For example, with semantic attribute processing enabled, this XML property file:

      <root>
        <properties>
          <foo location="bar"/>
          <quux>${root.properties.foo}</quux>
        </properties>
      </root>

is roughly equivalent to the following fragments in a build.xml file:

      <property name="root.properties.foo" location="bar"/>
      <property name="root.properties.quux" value="${root.properties.foo}"/>

### Parameters

Attribute | Description | Required
file | The XML file to parse. | Yes, or a nested resource collection.
prefix | The prefix to prepend to each property | No
keepRoot | Keep the xml root tag as the first value in the property name. | No, default is true.
validate | Validate the input file (e.g. by a DTD). Otherwise the XML must only be well-formed. | No, default is false.
collapseAttributes | Treat attributes as nested elements. | No, default is false.
semanticAttributes | Enable special handling of certain attribute names. See the Semantic Attributes section for more information. | No, default is false.
includeSemanticAttribute | Include the semantic attribute name as part of the property name. Ignored if semanticAttributes is not set to true. See the Semantic Attributes section for more information. | No, default is false.
rootDirectory | The directory to use for resolving file references. Ignored if semanticAttributes is not set to true. | No, default is `${basedir}`.
delimiter | Delimiter for splitting multiple values. since Apache Ant 1.7.1 | No, defaults to comma

### Nested Elements

#### xmlcatalog

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

#### any resource or single element resource collection

The specified resource will be used as input.

### Examples

#### Non-semantic Attributes

Here is an example xml file that does not have any semantic attributes.

       <root-tag myattr="true">
        <inner-tag someattr="val">Text</inner-tag>
        <a2><a3><a4>false</a4></a3></a2>
       </root-tag>

##### default loading

This entry in a build file:

       <xmlproperty file="somefile.xml"/>

is equivalent to the following properties:

       root-tag(myattr)=true
       root-tag.inner-tag=Text
       root-tag.inner-tag(someattr)=val
       root-tag.a2.a3.a4=false

##### collapseAttributes=false

This entry in a build file:

       <xmlproperty file="somefile.xml" collapseAttributes="true"/>

is equivalent to the following properties:

       root-tag.myattr=true
       root-tag.inner-tag=Text
       root-tag.inner-tag.someatt=val
       root-tag.a2.a3.a4=false

##### keepRoot=false

This entry in a build file:

       <xmlproperty file="somefile.xml" keepRoot="false"/>

is equivalent to the following properties:

       inner-tag=Text
       inner-tag(someattr)=val
       a2.a3.a4=false

#### Semantic Attributes

Here is an example xml file that has semantic attributes.

      <root-tag>
        <version value="0.0.1"/>
        <build folder="build">
          <classes id="build.classes" location="${build.folder}/classes"/>
          <reference refid="build.classes"/>
        </build>
        <compile>
          <classpath pathid="compile.classpath">
            <pathelement location="${build.classes}"/>
          </classpath>
        </compile>
        <run-time>
          <jars>*.jar</jars>
          <classpath pathid="run-time.classpath">
            <path refid="compile.classpath"/>
            <pathelement path="${run-time.jars}"/>
          </classpath>
        </run-time>
      </root-tag>

##### default loading (semanticAttributes=true)

This entry in a build file:

       <xmlproperty file="somefile.xml" keepRoot="false"
                    semanticAttributes="true"/>

is equivalent to the following entries in a build file:

      <property name="version" value="0.0.1"/>
      <property name="build.folder" value="build"/>
      <property name="build.classes" location="${build.folder}/classes" id="build.classes"/>
      <property name="build.reference" refid="build.classes"/>

      <property name="run-time.jars" value="*.jar"/>

      <path id="compile.classpath">
        <pathelement location="${build.classes}"/>
      </path>

      <path id="run-time.classpath">
        <path refid="compile.classpath"/>
        <pathelement path="${run-time.jars}"/>
      </path>

##### includeSemanticAttribute="true"

This entry in a build file:

       <xmlproperty file="somefile.xml"
                    semanticAttributes="true" keepRoot="false"
                    includeSemanticAttribute="true"/>

is equivalent to the following entries in a build file:

      <property name="version.value" value="0.0.1"/>
      <property name="build.folder" value="build"/>
      <property name="build.classes.location" location="${build.folder}/classes"/>
      <property name="build.reference.refid" refid="build.classes"/>

      <property name="run-time.jars" value="*.jar"/>

      <path id="compile.classpath">
        <pathelement location="${build.classes}"/>
      </path>

      <path id="run-time.classpath">
        <path refid="compile.classpath"/>
        <pathelement path="${run-time.jars}"/>
      </path>