refactor(storage,query): decompose storage & AST god classes, decouple CoreseIO, and purge legacy dead code

src/main/java/fr/inria/corese/core/next/query/api/io/package-info.java

@@ -5,8 +5,6 @@
  * enumerates the supported serialization formats for SPARQL SELECT and ASK
  * results (CSV, TSV, JSON, XML). Serializer contracts live in
  * {@code io.serializer}; reusable option facets live in
- * {@code io.serializer.option}.
- * The recommended high-level entry point is {@link
- * fr.inria.corese.core.next.io.CoreseIO}.</p>
+ * {@code io.serializer.option}.</p>
  */
 package fr.inria.corese.core.next.query.api.io;

src/main/java/fr/inria/corese/core/next/query/impl/engine/eval/Eval.java

@@ -23,7 +23,6 @@
 import fr.inria.corese.core.next.query.api.exception.QueryTypeErrorException;
 
 import fr.inria.corese.core.next.data.Values;
-import fr.inria.corese.core.next.query.impl.engine.event.ResultListener;
 import fr.inria.corese.core.next.query.impl.engine.model.NodeImpl;
 import fr.inria.corese.core.next.data.api.model.DatatypeValue;
 import org.slf4j.Logger;
@@ -109,7 +108,6 @@ public Eval(Producer p, Evaluator e, Matcher m) {
         evaluator = e;
         match = m;
         setVisitor(new ProcessVisitorDefault());
-        e.setKGRAM(this);
         graphEvaluator = new EvalGraph(this);
         join = new EvalJoin(this);
         optional = new EvalOptional(this);
@@ -724,9 +722,6 @@ int eval(Producer p, Node graphNode, Stack stack, Mappings map, int n) {
         state.updateMaxLevel(n);
 
         Exp exp = stack.get(n);
-        if (visitors.hasListener()) {
-            exp = visitors.listen(exp, n);
-        }
 
         // A false filter was detected at compile time, or this expression was
         // identified as always failing: no use to evaluate it.
@@ -973,9 +968,6 @@ private int edge(Producer p, Node graphNode, Exp exp, Mappings data, Stack stack
 
                 if (entity != null) {
                     state.incrementEdge();
-                    if (visitors.hasListener() && !visitors.listen(exp, qEdge, entity)) {
-                        continue;
-                    }
 
                     graph = entity.getGraph();
                     boolean bmatch = match(qEdge, entity, graphNode, graph, env);
@@ -1045,20 +1037,12 @@ Mappings selectQueryMappings(Mappings data) {
      * Store a new result
      */
     private int store(Producer p, Mapping m) {
-        boolean store = true;
-        if (getListener() != null) {
-            store = getListener().process(getMemory());
-        }
-        if (store) {
-            state.incrementResult();
-        }
-        if (store) {
-            Mapping ans = m;
-            if (m == null) {
-                ans = getMemory().store(getQuery(), p, isSubEval);
-            }
-            store(ans);
+        state.incrementResult();
+        Mapping ans = m;
+        if (m == null) {
+            ans = getMemory().store(getQuery(), p, isSubEval);
         }
+        store(ans);
         return -1;
     }
 
@@ -1149,14 +1133,6 @@ public boolean isJoinMappings() {
         return joinMappings;
     }
 
-    public ResultListener getListener() {
-        return visitors.getListener();
-    }
-
-    public void setListener(ResultListener listener) {
-        visitors.setListener(listener);
-    }
-
     public EvaluationState getState() {
         return state;
     }

src/main/java/fr/inria/corese/core/next/query/impl/engine/eval/EvalFilter.java

@@ -90,9 +90,6 @@ Mappings eval(Filter f, Environment env, Producer p, List<Node> nodes) {
         int n = 1;
         Expr exp = f.getExp();
         if (exp.oper() == UNNEST) {
-            if (engine.getVisitorDispatcher().hasListener()) {
-                engine.getVisitorDispatcher().listen(exp);
-            }
             if (exp.arity() == 2) {
                 DatatypeValue dt = eval(exp.getExp(1), env, p);
                 if (dt == null) {

src/main/java/fr/inria/corese/core/next/query/impl/engine/eval/EvalVisitorDispatcher.java

@@ -1,29 +1,19 @@
 package fr.inria.corese.core.next.query.impl.engine.eval;
 
-import fr.inria.corese.core.next.data.api.model.DatatypeValue;
 import fr.inria.corese.core.next.query.impl.engine.event.ProcessVisitor;
 import fr.inria.corese.core.next.query.impl.engine.event.ProcessVisitorDefault;
-import fr.inria.corese.core.next.query.impl.engine.event.ResultListener;
-import fr.inria.corese.core.next.query.impl.engine.model.Edge;
-import fr.inria.corese.core.next.query.impl.engine.model.Expr;
-import fr.inria.corese.core.next.query.impl.engine.model.Node;
-import fr.inria.corese.core.next.query.impl.engine.pattern.Exp;
 
 import java.util.Objects;
 
 /**
- * Coordinates and dispatches execution lifecycle visitors and result listeners
- * for SPARQL evaluation in {@link Eval}.
+ * Coordinates and dispatches execution lifecycle visitors for SPARQL evaluation in {@link Eval}.
  *
- * <p>Encapsulates the active {@link ProcessVisitor} (for query observation and reporting)
- * and the optional {@link ResultListener} (for inference rule execution).</p>
+ * <p>Encapsulates the active {@link ProcessVisitor} for query observation and reporting.</p>
  */
 public final class EvalVisitorDispatcher {
 
-    private ResultListener listener;
     private ProcessVisitor visitor;
 
-    private boolean hasListener = false;
     private boolean hasStatement = false;
     private boolean hasCandidate = false;
     private boolean hasFilter = false;
@@ -44,15 +34,9 @@ public void setVisitor(ProcessVisitor visitor) {
     }
 
     public void updateVisitorFlags() {
-        if (visitor != null) {
-            this.hasStatement = visitor.statement();
-            this.hasCandidate = visitor.candidate();
-            this.hasFilter = visitor.filter();
-        } else {
-            this.hasStatement = false;
-            this.hasCandidate = false;
-            this.hasFilter = false;
-        }
+        this.hasStatement = visitor.statement();
+        this.hasCandidate = visitor.candidate();
+        this.hasFilter = visitor.filter();
     }
 
     public boolean hasStatement() {
@@ -66,39 +50,4 @@ public boolean hasCandidate() {
     public boolean hasFilter() {
         return hasFilter;
     }
-
-    // --- Listener ---
-
-    public ResultListener getListener() {
-        return listener;
-    }
-
-    public void setListener(ResultListener listener) {
-        this.listener = listener;
-        this.hasListener = (listener != null);
-    }
-
-    public boolean hasListener() {
-        return hasListener;
-    }
-
-    public Exp listen(Exp exp, int n) {
-        if (hasListener) {
-            return listener.listen(exp, n);
-        }
-        return exp;
-    }
-
-    public void listen(Expr exp) {
-        if (hasListener) {
-            listener.listen(exp);
-        }
-    }
-
-    public boolean listen(Exp exp, Edge qEdge, Edge entity) {
-        if (hasListener) {
-            return listener.listen(exp, qEdge, entity);
-        }
-        return true;
-    }
 }

src/main/java/fr/inria/corese/core/next/query/impl/engine/eval/SparqlKgramEvaluator.java

@@ -18,20 +18,9 @@
 public final class SparqlKgramEvaluator implements Evaluator {
 
     private final OffsetDateTime queryEvaluationTime = OffsetDateTime.now(ZoneOffset.UTC);
-    private Mode mode = Mode.KGRAM_MODE;
 
     @Override
     public OffsetDateTime getQueryEvaluationTime() {
         return queryEvaluationTime;
     }
-
-    @Override
-    public Mode getMode() {
-        return mode;
-    }
-
-    @Override
-    public void setMode(Mode mode) {
-        this.mode = mode;
-    }
 }

src/main/java/fr/inria/corese/core/next/query/impl/engine/event/ProcessVisitorDefault.java

@@ -1,55 +1,7 @@
 package fr.inria.corese.core.next.query.impl.engine.event;
 
-import fr.inria.corese.core.next.query.impl.engine.eval.Eval;
-import fr.inria.corese.core.next.query.impl.engine.model.Node;
-import fr.inria.corese.core.next.query.impl.engine.pattern.Exp;
-import fr.inria.corese.core.next.query.impl.engine.solution.Mappings;
-
 /**
- * Default process visitor that forwards reporting events to the query binding context
- * when query report is enabled.
+ * Default process visitor providing no-op implementations of execution lifecycle events.
  */
 public final class ProcessVisitorDefault implements ProcessVisitor {
-
-    void visit(Eval eval, Node g, Exp e, Mappings m1, Mappings m2) {
-        if (eval.getQuery().isReportEnabled()) {
-            eval.getBind().visit(e, g, m1, m2);
-        }
-    }
-
-    @Override
-    public void graph(Eval eval, Node g, Exp e, Mappings m1) {
-        visit(eval, g, e, m1, null);
-    }
-
-    @Override
-    public void query(Eval eval, Node g, Exp e, Mappings m1) {
-        visit(eval, g, e, m1, null);
-    }
-
-    @Override
-    public void service(Eval eval, Node g, Exp e, Mappings m1) {
-        visit(eval, g, e, m1, null);
-    }
-
-    @Override
-    public void optional(Eval eval, Node g, Exp e, Mappings m1, Mappings m2) {
-        visit(eval, g, e, m1, m2);
-    }
-
-    @Override
-    public void minus(Eval eval, Node g, Exp e, Mappings m1, Mappings m2) {
-        visit(eval, g, e, m1, m2);
-    }
-
-    @Override
-    public void union(Eval eval, Node g, Exp e, Mappings m1, Mappings m2) {
-        visit(eval, g, e, m1, m2);
-    }
-
-    @Override
-    public void join(Eval eval, Node g, Exp e, Mappings m1, Mappings m2) {
-        visit(eval, g, e, m1, m2);
-    }
-
 }

src/main/java/fr/inria/corese/core/next/query/impl/engine/model/BindingContext.java

@@ -108,17 +108,4 @@ default ProcessVisitor getVisitor() {
     default void setVisitor(ProcessVisitor visitor) {
         // By default, do nothing
     }
-
-    /**
-     * Visit method for reporting.
-     * Used by ProcessVisitorDefault.
-     *
-     * @param e  the expression
-     * @param g  the graph node
-     * @param m1 the mappings 1
-     * @param m2 the mappings 2
-     */
-    default void visit(Object e, Object g, Object m1, Object m2) {
-        // By default, do nothing
-    }
 }

src/main/java/fr/inria/corese/core/next/query/impl/engine/model/Edge.java

@@ -75,14 +75,6 @@ default boolean isMatchArity() {
         return false;
     }
 
-    // nested rdf star triple <<s p o>>
-    default boolean isNested() {
-        return false;
-    }
-    default void setNested(boolean b) {
-        // RDF-star nesting is an optional capability of concrete edge implementations.
-    }
-
     default DatatypeValue getGraphValue() {
         Node node = getGraph();
         if (node == null) {

src/main/java/fr/inria/corese/core/next/query/impl/engine/model/ExpType.java

@@ -1,9 +1,7 @@
 package fr.inria.corese.core.next.query.impl.engine.model;
 
 /**
- * Types of expression of KGRAM query language
- *
- * @author Olivier Corby, Edelweiss, INRIA 2010
+ * Expression types for SPARQL query algebra in KGRAM engine.
  */
 public interface ExpType {
 
@@ -17,31 +15,21 @@ enum Type {
         FILTER("FILTER"),
         NODE("NODE"),
         BGP("BGP"),
-        WATCH("WATCH"),
-        CONTINUE("CONTINUE"),
-        BACKJUMP("BACKJUMP"),
         QUERY("QUERY"),
-        FORALL("FORALL"),
         EXIST("EXIST"),
         GRAPHNODE("GRAPHNODE"),
         OPTIONAL("OPTIONAL"),
-        SCAN("SCAN"),
-        IF("IF"),
-        XPATH("XPATH"),
         ACCEPT("ACCEPT"),
         BIND("BIND"),
-        EVAL("EVAL"),
-        SCOPE("SCOPE"),
         TEST("TEST"),
-        NEXT("NEXT"),
         MINUS("MINUS"),
-        POP("POP"),
         SERVICE("SERVICE"),
-        RESTORE("RESTORE"),
         JOIN("JOIN"),
         VALUES("VALUES"),
         OPT_BIND("OPT_BIND");
+
         private final String title;
+
         Type(String title) {
             this.title = title;
         }