Class XmlConfiguration


public class XmlConfiguration extends Object

Configures objects from XML.

This class reads an XML file conforming to the configure.dtd DTD and uses it to configure and object by calling set, put or other methods on the object.

The actual XML file format may be changed (eg to spring XML) by implementing the ConfigurationProcessorFactory interface to be found by the ServiceLoader by using the DTD and first tag element in the file. Note that DTD will be null if validation is off.

The configuration can be parameterised with properties that are looked up via the Property XML element and set on the configuration via the map returned from getProperties()

The configuration can create and lookup beans by ID. If multiple configurations are used, then it is good practise to copy the entries from the getIdMap() of a configuration to the next configuration so that they can share an ID space for beans.

  • Field Details

  • Constructor Details

    • XmlConfiguration

      public XmlConfiguration(Resource resource) throws SAXException, IOException
      Reads and parses the XML configuration file.
      resource - the Resource to the XML configuration
      IOException - if the configuration could not be read
      SAXException - if the configuration could not be parsed
  • Method Details

    • setJettyStandardIdsAndProperties

      public void setJettyStandardIdsAndProperties(Object server, Resource webapp)
      Set the standard IDs and properties expected in a jetty XML file:
      • RefId Server
      • Property jetty.home
      • Property jetty.home.uri
      • Property jetty.base
      • Property jetty.base.uri
      • Property jetty.webapps
      • Property jetty.webapps.uri
      server - The Server object to set
      webapp - The webapps Resource
    • normalizeURI

      public static String normalizeURI(String uri)
    • toString

      public String toString()
      toString in class Object
    • getIdMap

      public Map<String,Object> getIdMap()
      Get the map of ID String to Objects that is used to hold and lookup any objects by ID.

      A New, Get or Call XML element may have an id attribute which will cause the resulting object to be placed into this map. A Ref XML element will lookup an object from this map.

      When chaining configuration files, it is good practise to copy the ID entries from the ID map to the map of the next configuration, so that they may share an ID space

      A modifiable map of ID strings to Objects
    • getProperties

      public Map<String,String> getProperties()
      Get the map of properties used by the Property XML element to parametrize configuration.
      A modifiable map of properties.
    • configure

      public Object configure(Object obj) throws Exception
      Applies the XML configuration script to the given object.
      obj - The object to be configured, which must be of a type or super type of the class attribute of the <Configure> element.
      the configured object
      Exception - if the configuration fails
    • configure

      public Object configure() throws Exception
      Applies the XML configuration script. If the root element of the configuration has an ID, an object is looked up by ID and its type checked against the root element's type. Otherwise a new object of the type specified by the root element is created.
      The newly created configured object.
      Exception - if the configuration fails
    • initializeDefaults

      public void initializeDefaults(Object object)
      Initialize a new Object defaults.

      This method must be called by any ConfigurationProcessor when it creates a new instance of an object before configuring it, so that a derived XmlConfiguration class may inject default values.

      object - the object to initialize defaults on
    • resolvePath

      public static String resolvePath(String dir, String destPath)
      Utility method to resolve a provided path against a directory.
      dir - the directory (should be a directory reference, does not have to exist)
      destPath - the destination path (can be relative or absolute, syntax depends on OS + FileSystem in use, and does not need to exist)
      String to resolved and normalized path, or null if dir or destPath is empty.
    • main

      public static void main(String... args) throws Exception
      Runs the XML configurations as a main application. The command line is used to obtain properties files (must be named '*.properties') and XmlConfiguration files.

      Any property file on the command line is added to a combined Property instance that is passed to each configuration file via getProperties().

      Each configuration file on the command line is used to create a new XmlConfiguration instance and the configure() method is used to create the configured object. If the resulting object is an instance of LifeCycle, then it is started.

      Any IDs created in a configuration are passed to the next configuration file on the command line using getIdMap(). This allows objects with IDs created in one config file to be referenced in subsequent config files on the command line.

      args - array of property and xml configuration filenames or Resources.
      Exception - if the XML configurations cannot be run