This document specifies a syntax created by subsetting an existing, widelyused international text processing standard (Standard Generalized Markup Language,ISO 8879:1986(E) as amended and corrected) for use on the World Wide Web.It is a product of the XML Core Working Groupas part of the XML Activity.The English version of this specification is the only normative version. However,for translations of this document, see =xml.
This document is a W3C Recommendation. This fifth edition is not a new version of XML. As a convenience to readers,it incorporates the changes dictated by the accumulated errata (available at -V10-4e-errata) to the FourthEdition of XML 1.0, dated 16 August 2006. In particular, erratum [E09]relaxes the restrictions on element and attribute names, thereby providing in XML 1.0 the major end user benefitcurrently achievable only by using XML1.1. As a consequence, many possible documents which were not well-formed according to previous editions of this specification are now well-formed, and previously invalid documentsusing the newly-allowed name characters in, for example, IDattributes, are now valid.
Visual Prolog Version 5.2 22
Please report errors in this document tothe public xml-editor@w3.org mail list; publicarchives are available. For the convenience of readers,an XHTML version with color-coded revision indicators isalso provided; this version highlights each change due to an erratum published in theerratalist for the previous edition, together with a link to the particularerratum in that list. Most of theerrata in the list provide a rationale for the change. The erratalist for this fifth edition is available at -V10-5e-errata.
[Definition: A parsed entity contains text,a sequence of characters, which mayrepresent markup or character data.][Definition: A characteris an atomic unit of text as specified by ISO/IEC 10646:2000 [ISO/IEC 10646]. Legal characters are tab, carriagereturn, line feed, and the legal charactersof Unicode and ISO/IEC 10646. Theversions of these standards cited in A.1 Normative References werecurrent at the time this document was prepared. New characters may be addedto these standards by amendments or new editions. Consequently, XML processorsMUST accept any character in the range specified for Char.]
PIs are not part of the document's characterdata, but MUST be passed through to the application. The PI beginswith a target (PITarget) used to identify the applicationto which the instruction is directed. The target names "XML", "xml",and so on are reserved for standardization in this or future versions of thisspecification. The XML Notation mechanismmay be used for formal declaration of PI targets. Parameterentity references MUST NOT be recognized within processing instructions.
When an XML 1.0 processor encounters a document that specifiesa 1.x version number other than '1.0', it will process it asa 1.0 document. This means that an XML 1.0 processor will accept1.x documents provided they do not use any non-1.0 features.
In editing XML documents, it is often convenient to use "white space"(spaces, tabs, and blank lines)to set apart the markup for greater readability. Such white space is typicallynot intended for inclusion in the delivered version of the document. On theother hand, "significant" white space that should be preservedin the delivered version is common, for example in poetry and source code.
This specification does not constrain theapplication semantics, use, or (beyond syntax)names of the element types and attributes, except that names beginning witha match to (('X''x')('M''m')('L''l')) are reserved for standardizationin this or future versions of this specification.
This rule is based on the recognition that the automatic inclusion providedby the SGML and XML entity mechanism, primarily designed to support modularityin authoring, is not necessarily appropriate for other applications, in particulardocument browsing. Browsers, for example, when encountering an external parsedentity reference, might choose to provide a visual indication of the entity'spresence and retrieve it for display only on demand.
Once the processor has detected the character encoding in use, it can actappropriately, whether by invoking a separate input routine for each case,or by calling the proper conversion function on each character of input.
The following suggestions define what is believed to be bestpractice in the construction of XML names used as element names,attribute names, processing instruction targets, entity names,notation names, and the values of attributes of type ID, and areintended as guidance for document authors and schema designers.All references to Unicode are understood with respect toa particular version of the Unicode Standard greater than or equalto 5.0; which version should be used is left to the discretion ofthe document author or schema designer.
The first two suggestions are directly derived from the rulesgiven for identifiers in Standard Annex #31 (UAX #31) of the Unicode Standard, version 5.0 [Unicode], andexclude all control characters, enclosing nonspacing marks,non-decimal numbers, private-use characters, punctuation characters(with the noted exceptions), symbol characters, unassignedcodepoints, and white space characters. The other suggestionsare mostly derived from Appendix B in previous editions of this specification.
Layrry - A Launcher and API for Modularized Java Applications. It allows to assemble modularized applications based on Maven artifact coordinates of the (modular) JARs to include. Layrry utilizes the Java Module System's notion of module layers, allowing multiple versions of one module to be used within an application at the same time, as well as dynamically adding and removing modules at application runtime.
Typically in a modern OO application you would use a rule engine to contain key parts of your business logic, especially the really messy parts. This is an inversion of the OO concept of encapsulating all the logic inside your objects. This is not to say that you throw out OO practices, on the contrary in any real world application, business logic is just one part of the application. If you ever notice lots of conditional statements such as "if" and "switch", an overabundance of strategy patterns and other messy logic in your code that just doesn't feel right: that would be a place for rules. If there is some such logic and you keep coming back to fix it, either because you got it wrong, or the logic or your understanding changes: think about using rules. If you are faced with tough problems for which there are no algorithms or patterns: consider using rules.
The Knowlege Agent provides automatic loading, caching and re-loading of resources and is configured from a properties files. The Knowledge Agent can update or rebuild this Knowlege Base as the resources it uses are changed. The strategy for this is determined by the configuration given to the factory, but it is typically pull-based using regular polling. We hope to add push-based updates and rebuilds in future versions.
The Rete algorithm was invented by Dr. Charles Forgy and documented in his PhD thesis in 1978-79. A simplified version of the paper was published in 1982 ( ). The latin word "rete" means "net" or "network". The Rete algorithm can be broken into 2 parts: rule compilation and runtime execution.
Knowledge Packages are added to the Knowledge Base. However, a Knowledge Package instance cannot be reused once it's added to the Knowledge Base. If you need to add it to another Knowledge Base, try serializing it first and using the "cloned" result. We hope to fix this limitation in future versions of Drools.
The KnowlegeAgent provides automatic loading, caching and re-loading of resources and is configured from a properties files. The Knowledge Agent can update or rebuild this Knowlege Base as the resources it uses are changed. The strategy for this is determined by the configuration given to the factory, but it is typically pull-based using regular polling. We hope to add push-based updates and rebuilds in future versions. The Knowledge Agent will continuously scan all the added resources, using a default polling interval of 60 seconds. If their date of the last modification is updated it will rebuild the cached Knowledge Base using the new resources.
Whenever a ruleflow-group becomes active or an agenda-group receives the focus, any rule within that group that has lock-on-active set to true will not be activated any more; irrespective of the origin of the update, the activation of a matching rule is discarded. This is a stronger version of no-loop, because the change could now be caused not only by the rule itself. It's ideal for calculation rules where you have a number of rules that modify a fact and you don't want any rule re-matching and firing again. Only when the ruleflow-group is no longer active or the agenda-group loses the focus those rules with lock-on-active set to true become eligible again for their activations to be placed onto the agenda.
There are several scenarios that XML is desirable. However, we recommend that it is not a default choice, as XML is not readily human readable (unless you like headaches) and can create visually bloated rules.
If you do want to edit XML by hand, use a good schema aware editor that provides nice hierarchical views of the XML, ideally visually (commercial tools like XMLSpy, Oxygen etc are good, but cost money, but then so do headache tablets).
Some applications provide a limited ability to keep a history of changes, but it is recommended to use an alternative means of revision control. When changes are being made to rules over time, older versions are archived (many open source solutions exist for this, such as Subversion or Git).
You can see from the example above that the rule group is using a domain specific language. Note the expander keyword, which tells the rule compiler to look for a dsl file of that name, to resolve the rule language. Even with the domain specific language (DSL) the rules are still stored as plain text as you see it onscreen, which allows simpler management of rules and versions, e.g., comparing versions of rules. 2ff7e9595c
Comentarios