[Jboss-svn-commits] JBL Code SVN: r2096 - trunk/labs/jbossrules/drools-core/src/main/java/org/drools/lang

[<jbo...@li...>]

Author: mic...@jb...
Date: 2006-01-13 21:52:11 -0500 (Fri, 13 Jan 2006)
New Revision: 2096

Added:
   trunk/labs/jbossrules/drools-core/src/main/java/org/drools/lang/Expander.java
   trunk/labs/jbossrules/drools-core/src/main/java/org/drools/lang/ExpanderContext.java
Log:
Expander skeleton

Added: trunk/labs/jbossrules/drools-core/src/main/java/org/drools/lang/Expander.java
===================================================================
--- trunk/labs/jbossrules/drools-core/src/main/java/org/drools/lang/Expander.java	2006-01-13 21:10:43 UTC (rev 2095)
+++ trunk/labs/jbossrules/drools-core/src/main/java/org/drools/lang/Expander.java	2006-01-14 02:52:11 UTC (rev 2096)
@@ -0,0 +1,16 @@
+package org.drools.lang;
+
+/**
+ * Expanders provide just in time expansion for expressions in DRL.
+ * 
+ * Expanders should ideally not make presumptions on any embedded semantic 
+ * language. For instance, java aware pre processing should be done in
+ * drools-java semantic module, not in the parser itself. Expanders should 
+ * be reusable across semantic languages. 
+ * 
+ * @author Michael Neale
+ *
+ */
+public interface Expander {
+
+}


Property changes on: trunk/labs/jbossrules/drools-core/src/main/java/org/drools/lang/Expander.java
___________________________________________________________________
Name: svn:eol-style
   + native

Added: trunk/labs/jbossrules/drools-core/src/main/java/org/drools/lang/ExpanderContext.java
===================================================================
--- trunk/labs/jbossrules/drools-core/src/main/java/org/drools/lang/ExpanderContext.java	2006-01-13 21:10:43 UTC (rev 2095)
+++ trunk/labs/jbossrules/drools-core/src/main/java/org/drools/lang/ExpanderContext.java	2006-01-14 02:52:11 UTC (rev 2096)
@@ -0,0 +1,71 @@
+package org.drools.lang;
+
+import java.io.Serializable;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * Expanders are extension points for expanding 
+ * expressions in DRL at parse time.
+ * This is just-in-time translation, or macro expansion, or
+ * whatever you want.
+ * 
+ * The important thing is that it happens at the last possible moment, 
+ * so any errors in expansion are included in the parsers errors.
+ * 
+ * Just-in-time expansions may include complex pre-compilers, 
+ * or just macros, and everything in between.
+ * 
+ * @author <a href="mailto:mic...@gm..."> Michael Neale</a>
+ *
+ */
+public class ExpanderContext implements Serializable {
+
+	private static final long serialVersionUID = 1806461802987228880L;
+	private boolean enabled = true;
+	
+	private final Set expanders;
+	
+	/**
+	 * This indicates that at least one expander has been configured for 
+	 * this parser configuration.
+	 */
+	public boolean isEnabled() {
+		return enabled;
+	}
+	
+	public ExpanderContext(Collection initialExpanders) {
+		enabled = true;
+		this.expanders = new HashSet(initialExpanders);
+	}
+	
+	public ExpanderContext() {	
+		this.expanders = new HashSet();
+	}
+	
+	public ExpanderContext addExpander(Expander exp) {
+		expanders.add(exp);
+		return this;
+	}
+	
+	/**
+	 * Expands the expression Just-In-Time for the parser.
+	 * If the expression is not meant to be expanded, or if no
+	 * appropriate expander is found, it will echo back the same 
+	 * expression.
+	 * 
+	 * @param expression The "line" or expression to be expanded/pre-compiled.
+	 * @param context The context of the current state of parsing. This can help
+	 * the expander know if it needs to expand, what to do etc.
+	 * 
+	 * If <code>isEnabled()</code> is false then it is not required to 
+	 * call this method.
+	 */
+	public String expand(String expression, RuleParser context) {
+		return expression;
+	}
+	
+	
+	
+}


Property changes on: trunk/labs/jbossrules/drools-core/src/main/java/org/drools/lang/ExpanderContext.java
___________________________________________________________________
Name: svn:eol-style
   + native