Dev restart

parsers/src/main/java/org/chocosolver/parser/xcsp/XCSP.java

@@ -9,7 +9,7 @@
  */
 package org.chocosolver.parser.xcsp;
 
-import org.chocosolver.cutoffseq.LubyCutoffStrategy;
+import org.chocosolver.solver.search.restart.LubyCutoff;
 import org.chocosolver.parser.Level;
 import org.chocosolver.parser.RegParser;
 import org.chocosolver.solver.Model;
@@ -124,7 +124,7 @@ public void parse(Model target, XCSPParser parser, int i) throws Exception {
             Solver solver = target.getSolver();
             solver.setSearch(Search.defaultSearch(target));
             solver.setNoGoodRecordingFromRestarts();
-            solver.setRestarts(count -> solver.getFailCount() >= count, new LubyCutoffStrategy(500), 5000);
+            solver.setRestarts(count -> solver.getFailCount() >= count, new LubyCutoff(500), 5000);
         }
     }
 

solver/src/main/java/module-info.java

@@ -21,8 +21,7 @@
     exports org.chocosolver.memory.trailing.trail.flatten;
     exports org.chocosolver.memory.trailing.trail.chunck;
     exports org.chocosolver.memory.structure;
-
-    exports org.chocosolver.cutoffseq;
+
     exports org.chocosolver.sat;
     exports org.chocosolver.solver;
     exports org.chocosolver.solver.learn;
@@ -159,5 +158,4 @@
     exports org.chocosolver.solver.constraints.nary.knapsack.structure;
     opens org.chocosolver.solver.constraints.nary.knapsack.structure to org.chocosolver.parsers;
 
-
 }

solver/src/main/java/org/chocosolver/solver/ParallelPortfolio.java

@@ -9,7 +9,7 @@
  */
 package org.chocosolver.solver;
 
-import org.chocosolver.cutoffseq.LubyCutoffStrategy;
+import org.chocosolver.solver.search.restart.LubyCutoff;
 import org.chocosolver.solver.constraints.Constraint;
 import org.chocosolver.solver.constraints.nary.sat.NogoodStealer;
 import org.chocosolver.solver.constraints.real.RealConstraint;
@@ -354,6 +354,7 @@ public List<Model> getModels() {
      * @return a list that contained the found solutions.
      */
     public Stream<Solution> streamSolutions() {
+        //noinspection Convert2Diamond
         Spliterator<Solution> it = new Spliterator<Solution>() {
 
             @Override
@@ -388,7 +389,6 @@ public int characteristics() {
     ///////////////////////////////////////   INTERNAL METHODS    //////////////////////////////////////////////////////
     ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 
-    @SuppressWarnings("unchecked")
     public void prepare() {
         isPrepared = true;
         check();
@@ -597,7 +597,7 @@ private void configureModel(int workerID) {
                 if (reliableness.containsKey(worker)) {
                     solver.plugMonitor(new NogoodFromRestarts(worker, manager));
                 }
-                solver.setRestarts(count -> solver.getFailCount() >= count, new LubyCutoffStrategy(500), 5000);
+                solver.setRestarts(count -> solver.getFailCount() >= count, new LubyCutoff(500), 5000);
                 break;
         }
         // complete with set default search

solver/src/main/java/org/chocosolver/solver/Solver.java

@@ -33,6 +33,7 @@
 import org.chocosolver.solver.search.loop.propagate.PropagateBasic;
 import org.chocosolver.solver.search.measure.IMeasures;
 import org.chocosolver.solver.search.measure.MeasuresRecorder;
+import org.chocosolver.solver.search.restart.AbstractRestart;
 import org.chocosolver.solver.search.strategy.Search;
 import org.chocosolver.solver.search.strategy.decision.Decision;
 import org.chocosolver.solver.search.strategy.decision.DecisionPath;
@@ -225,6 +226,11 @@ public enum Action {
      */
     private boolean canBeRepaired = true;
 
+    /**
+     * The restarting strategy
+     */
+    private AbstractRestart restarter;
+
     /**
      * This object is accessible lazily
      */
@@ -265,6 +271,7 @@ protected Solver(Model aModel) {
         setMove(new MoveBinaryDFS());
         setPropagate(new PropagateBasic());
         setNoLearning();
+        restarter = AbstractRestart.NO_RESTART;
     }
 
     public void throwsException(ICause c, Variable v, String s) throws ContradictionException {
@@ -445,6 +452,7 @@ protected boolean initialize() {
             warmStart.setStrategy(declared);
             setSearch(warmStart);
         }
+        restarter.init();
         if (!M.init()) { // the initialisation of the Move and strategy can detect inconsistency
             mModel.getEnvironment().worldPop();
             feasible = FALSE;
@@ -498,10 +506,11 @@ private void fixpoint() {
     protected void extend() {
         searchMonitors.beforeOpenNode();
         mMeasures.incNodeCount();
-        if (!M.extend(this)) {
+        action = propagate;
+        if (restarter.mustRestart(this)) {
+            this.restart();
+        } else if (!M.extend(this)) {
             action = validate;
-        } else {
-            action = propagate;
         }
         searchMonitors.afterOpenNode();
     }
@@ -520,7 +529,12 @@ protected void repair() {
             action = propagate;
         }
         searchMonitors.beforeUpBranch();
-        canBeRepaired = M.repair(this);
+        if (restarter.mustRestart(this)) {
+            canBeRepaired = true;
+            this.restart();
+        } else {
+            canBeRepaired = M.repair(this);
+        }
         searchMonitors.afterUpBranch();
         if (!canBeRepaired) {
             stop = true;
@@ -652,7 +666,7 @@ public void hardReset() {
         setNoLearning();
         //no need to unplug, done by searchMonitors.reset()
         this.lastSol = null;
-        if(this.warmStart != null) {
+        if (this.warmStart != null) {
             this.warmStart.clearHints();
             this.warmStart = null;
         }
@@ -1126,6 +1140,38 @@ public void setPropagate(Propagate p) {
         this.P = p;
     }
 
+    /**
+     * Add or complete a restart policy.
+     * If no policy is defined, this method declares <i>restarter</i> as the current strategy.
+     * If a policy is defined, this method adds <i>restarter</i> as the next policy to check.
+     *
+     * @param restarter restarter policy
+     * @see #clearRestarter()
+     */
+    public void addRestarter(AbstractRestart restarter) {
+        if (this.restarter == AbstractRestart.NO_RESTART) {
+            this.restarter = restarter;
+        } else {
+            this.restarter.setNext(restarter);
+        }
+    }
+
+    /**
+     * @return the current declared restart policy or {@link AbstractRestart#NO_RESTART}
+     */
+    public AbstractRestart getRestarter() {
+        return this.restarter;
+    }
+
+    /**
+     * Clear the declared restart strategy.
+     * Consequently, no restarting will occur.
+     * @implNote replace the declared restart policy by {@link AbstractRestart#NO_RESTART}
+     */
+    public void clearRestarter() {
+        this.restarter = AbstractRestart.NO_RESTART;
+    }
+
     /**
      * Declares an objective manager to use.
      *
@@ -1487,6 +1533,7 @@ public Logger log() {
     /**
      * Defines whether (when {@code ansi} is set to {@code true}) or not
      * ANSI tags are added to any trace from choco-solver.
+     *
      * @param ansi {@code true} to enable colors
      */
     public void logWithANSI(boolean ansi) {