--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dwtx/core/runtime/jobs/MultiRule.d	Tue Aug 12 02:34:21 2008 +0200
@@ -0,0 +1,192 @@
+/*******************************************************************************
+ * Copyright (c) 2003, 2008 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     IBM - Initial API and implementation
+ * Port to the D programming language:
+ *     Frank Benoit <benoit@tionex.de>
+ *******************************************************************************/
+module dwtx.core.runtime.jobs.MultiRule;
+
+import dwt.dwthelper.utils;
+import dwtx.dwtxhelper.Collection;
+
+import dwtx.core.runtime.jobs.ISchedulingRule;
+
+/**
+ * A MultiRule is a compound scheduling rule that represents a fixed group of child
+ * scheduling rules.  A MultiRule conflicts with another rule if any of its children conflict
+ * with that rule.  More formally, a compound rule represents a logical intersection
+ * of its child rules with respect to the <code>isConflicting</code> equivalence
+ * relation.
+ * <p>
+ * A MultiRule will never contain other MultiRules as children.  If a MultiRule is provided
+ * as a child, its children will be added instead.
+ * </p>
+ *
+ * @since 3.0
+ * @noextend This class is not intended to be subclassed by clients.
+ */
+public class MultiRule : ISchedulingRule {
+    private ISchedulingRule[] rules;
+
+    /**
+     * Returns a scheduling rule that encompasses all provided rules.  The resulting
+     * rule may or may not be an instance of <code>MultiRule</code>.  If all
+     * provided rules are <code>null</code> then the result will be
+     * <code>null</code>.
+     *
+     * @param ruleArray An array of scheduling rules, some of which may be <code>null</code>
+     * @return a combined scheduling rule, or <code>null</code>
+     * @since 3.1
+     */
+    public static ISchedulingRule combine(ISchedulingRule[] ruleArray) {
+        ISchedulingRule result = null;
+        for (int i = 0; i < ruleArray.length; i++) {
+            if (ruleArray[i] is null)
+                continue;
+            if (result is null) {
+                result = ruleArray[i];
+                continue;
+            }
+            result = combine(result, ruleArray[i]);
+        }
+        return result;
+    }
+
+    /**
+     * Returns a scheduling rule that encompasses both provided rules.  The resulting
+     * rule may or may not be an instance of <code>MultiRule</code>.  If both
+     * provided rules are <code>null</code> then the result will be
+     * <code>null</code>.
+     *
+     * @param rule1 a scheduling rule, or <code>null</code>
+     * @param rule2 another scheduling rule, or <code>null</code>
+     * @return a combined scheduling rule, or <code>null</code>
+     */
+    public static ISchedulingRule combine(ISchedulingRule rule1, ISchedulingRule rule2) {
+        if (rule1 is rule2)
+            return rule1;
+        if (rule1 is null)
+            return rule2;
+        if (rule2 is null)
+            return rule1;
+        if (rule1.contains(rule2))
+            return rule1;
+        if (rule2.contains(rule1))
+            return rule2;
+        MultiRule result = new MultiRule();
+        result.rules = [rule1, rule2];
+        //make sure we don't end up with nested multi-rules
+        if (cast(MultiRule)rule1  || cast(MultiRule)rule2 )
+            result.rules = flatten(result.rules);
+        return result;
+    }
+
+    /*
+     * Collapses an array of rules that may contain MultiRules into an
+     * array in which no rules are MultiRules.
+     */
+    private static ISchedulingRule[] flatten(ISchedulingRule[] nestedRules) {
+        ArrayList myRules = new ArrayList(nestedRules.length);
+        for (int i = 0; i < nestedRules.length; i++) {
+            if (cast(MultiRule)nestedRules[i] ) {
+                ISchedulingRule[] children = (cast(MultiRule) nestedRules[i]).getChildren();
+                for (int j = 0; j < children.length; j++)
+                    myRules.add(cast(Object)children[j]);
+            } else {
+                myRules.add(cast(Object)nestedRules[i]);
+            }
+        }
+        return arraycast!(ISchedulingRule)( myRules.toArray() );
+    }
+
+    /**
+     * Creates a new scheduling rule that composes a set of nested rules.
+     *
+     * @param nestedRules the nested rules for this compound rule.
+     */
+    public this(ISchedulingRule[] nestedRules) {
+        this.rules = flatten(nestedRules);
+    }
+
+    /**
+     * Creates a new scheduling rule with no nested rules. For
+     * internal use only.
+     */
+    private this() {
+        //to be invoked only by factory methods
+    }
+
+    /**
+     * Returns the child rules within this rule.
+     * @return the child rules
+     */
+    public ISchedulingRule[] getChildren() {
+        return rules.dup;
+    }
+
+    /* (non-Javadoc)
+     * @see dwtx.core.runtime.jobs.ISchedulingRule#contains(dwtx.core.runtime.jobs.ISchedulingRule)
+     */
+    public bool contains(ISchedulingRule rule) {
+        if (this is rule)
+            return true;
+        if (cast(MultiRule)rule ) {
+            ISchedulingRule[] otherRules = (cast(MultiRule) rule).getChildren();
+            //for each child of the target, there must be some child in this rule that contains it.
+            for (int other = 0; other < otherRules.length; other++) {
+                bool found = false;
+                for (int mine = 0; !found && mine < rules.length; mine++)
+                    found = rules[mine].contains(otherRules[other]);
+                if (!found)
+                    return false;
+            }
+            return true;
+        }
+        for (int i = 0; i < rules.length; i++)
+            if (rules[i].contains(rule))
+                return true;
+        return false;
+    }
+
+    /* (non-Javadoc)
+     * @see dwtx.core.runtime.jobs.ISchedulingRule#isConflicting(dwtx.core.runtime.jobs.ISchedulingRule)
+     */
+    public bool isConflicting(ISchedulingRule rule) {
+        if (this is rule)
+            return true;
+        if (cast(MultiRule)rule ) {
+            ISchedulingRule[] otherRules = (cast(MultiRule) rule).getChildren();
+            for (int j = 0; j < otherRules.length; j++)
+                for (int i = 0; i < rules.length; i++)
+                    if (rules[i].isConflicting(otherRules[j]))
+                        return true;
+        } else {
+            for (int i = 0; i < rules.length; i++)
+                if (rules[i].isConflicting(rule))
+                    return true;
+        }
+        return false;
+    }
+
+    /*
+     * For debugging purposes only.
+     */
+    public String toString() {
+        StringBuffer buffer = new StringBuffer();
+        buffer.append("MultiRule["); //$NON-NLS-1$
+        int last = rules.length - 1;
+        for (int i = 0; i < rules.length; i++) {
+            buffer.append(rules[i] ? (cast(Object)rules[i]).toString() : "null" );
+            if (i !is last)
+                buffer.append(',');
+        }
+        buffer.append(']');
+        return buffer.toString();
+    }
+}