org.jbpm.pvm.internal.wire.xml
Class WireParser

java.lang.Object
  org.jbpm.pvm.internal.xml.Parser
      org.jbpm.pvm.internal.wire.xml.WireParser

public class WireParser
extends Parser

parses object wiring xml and constructs a WireDefinition.

To learn the full XML syntax, check out the xsd docs

• To describe an object:
  
  • <object .../>: see ObjectBinding
• To describe basic types:
  
  • <boolean .../>, <true /> and <false/>: see BooleanBinding
  • <byte .../>: see ByteBinding
  • <char .../>: see CharBinding
  • <double .../>: see DoubleBinding
  • <float .../>: see FloatBinding
  • <int .../>: see IntBinding
  • <string .../>: see StringBinding
• To describe collections:
  
  • <map .../>: see MapBinding
  • <set .../>: see SetBinding
  • <list .../>: see ListBinding
• Others:
  
  • <class .../>: see ClassBinding
  • <ref .../>: see RefBinding
  • <null .../>: see NullBinding

Bindings

The defaults bindings for the Wiring XML are divided in two categories:

• Descriptors, registered with the CATEGORY_DESCRIPTOR category
• Operations, registered with the CATEGORY_OPERATION category

Once a parser is created, bindings can be added, overwritten and removed to customize that parser instance.

Describing arguments

An ArgDescriptor is defined by a <arg> xml element.

This element can have an attribute "type", which specifies name of the argument's type.

This element contains one child element that defines a Descriptor. This descriptor specifies the value to give to the argument.

Example

Consider the following class:

 public class Hello {
   public static String sayHello(String name) {
     return "Hello " + name + " !";
   }
 }

The following Xml declaration will create an object 's' of class 'String' (see ObjectDescriptor). This object is created by invoking Hello.sayHello with the value world as a parameter.

 <objects>
   <object name="s" class='Hello' method='sayHello'>
     <arg>
      <string value='world' />
     </arg>
   </object>
 </objects>

The created object 's' will be a String, containing "Hello world !".

Initialization

The initialization method can be defined with the init attribute. For more details on how initialization works, see section 'Initialization' of WireContext.

The init attribute can have these values:

• lazy: for lazy creation and delayed initialization
• required: for lazy creation and immediate initialization
• eager: for eager creation and delayed initialization
• immediate: for eager creation and immediate initialization

Author:

Tom Baeyens, Guillaume Porcher (documentation)

Field Summary

static java.lang.String	CATEGORY_DESCRIPTOR
static java.lang.String	CATEGORY_INTERCEPTOR
static java.lang.String	CATEGORY_OPERATION
static java.lang.String[]	DEFAULT_WIRE_BINDING_RESOURCES

Fields inherited from class org.jbpm.pvm.internal.xml.Parser

bindings, documentBuilderFactory

Constructor Summary

WireParser()
Constructs a new WireParser with the default bindings.

Method Summary

static WireParser	getInstance() Default method to get an instance of the WireParser
java.lang.Object	parseDocumentElement(org.w3c.dom.Element documentElement, Parse parse) This method builds the WireDefinition from the DOM tree.
java.lang.Object	parseElement(org.w3c.dom.Element element, Parse parse, java.lang.String category) This method parses an arbitrary element in the document based on the bindings in the given category.
static WireDefinition	parseXmlString(java.lang.String xmlString) Convenience method to parse a wiring xml.

Methods inherited from class org.jbpm.pvm.internal.xml.Parser

buildDocument, createDocumentBuilder, createDocumentBuilderFactory, createParse, execute, getBinding, getBinding, getBindings, importStream, parseArgs, parseArgs, parseDocument, parseElement, setBindings, setSchemaResources

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_WIRE_BINDING_RESOURCES

public static final java.lang.String[] DEFAULT_WIRE_BINDING_RESOURCES

CATEGORY_DESCRIPTOR

public static final java.lang.String CATEGORY_DESCRIPTOR

See Also:

Constant Field Values

CATEGORY_OPERATION

public static final java.lang.String CATEGORY_OPERATION

See Also:

Constant Field Values

CATEGORY_INTERCEPTOR

public static final java.lang.String CATEGORY_INTERCEPTOR

See Also:

Constant Field Values

Constructor Detail

WireParser

public WireParser()

Constructs a new WireParser with the default bindings.

Method Detail

getInstance

public static WireParser getInstance()

Default method to get an instance of the WireParser

Returns:

the static instance of WireParser

parseXmlString

public static WireDefinition parseXmlString(java.lang.String xmlString)

Convenience method to parse a wiring xml.

Parameters:

xmlString - the xml string to parse

Returns:

the WireDefinition created by parsing the xml given in input.

See Also:

parseXmlString(String)

parseDocumentElement

public java.lang.Object parseDocumentElement(org.w3c.dom.Element documentElement,
                                             Parse parse)

This method builds the WireDefinition from the DOM tree. This methods parses all child activities of the documentElement that correspond to a Descriptor definition.

Overrides:

parseDocumentElement in class Parser

Parameters:

documentElement - the root element of the document

parse - Parse object that contains all information for the current parse operation.

Returns:

an instance of WireDefinition containing the resulting WireDefinition.

See Also:

Parser.parseDocumentElement(Element, Parse)

parseElement

public java.lang.Object parseElement(org.w3c.dom.Element element,
                                     Parse parse,
                                     java.lang.String category)

This method parses an arbitrary element in the document based on the bindings in the given category. This method calls the Parser.parseElement(Element, Parse, String) method to build the resulting object. If the resulting object is a subclass of AbstractDescriptor, the related fields are initialized.

Overrides:

parseElement in class Parser

Parameters:

element - the element to parse

parse - Parse object that contains all information for the current parse operation.

category - is the category in which the tagName should be resolved to an ElementHandler. If category is null, all the categories will be scanned for an appropriate binding in random order.

Returns:

the java object created from the DOM element