Bug#246 sparql plural values

jopa-impl/src/main/java/cz/cvut/kbss/jopa/query/parameter/CollectionParameterValue.java

@@ -17,6 +17,9 @@
  */
 package cz.cvut.kbss.jopa.query.parameter;
 
+import cz.cvut.kbss.jopa.query.sparql.SparqlConstants;
+
+import java.util.ArrayList;
 import java.util.List;
 import java.util.stream.Collectors;
 
@@ -29,12 +32,30 @@ class CollectionParameterValue extends AbstractParameterValue {
     }
 
     @Override
-    public Object getValue() {
+    public List<Object> getValue() {
         return values.stream().map(ParameterValue::getValue).collect(Collectors.toList());
     }
 
     @Override
     public String getQueryString() {
         return values.stream().map(ParameterValue::getQueryString).collect(Collectors.joining(","));
     }
+
+    @Override
+    public List<String> toQueryValues(int size) {
+        assert size >= values.size();
+        final List<String> result = new ArrayList<>(size);
+        values.stream().map(ParameterValue::getQueryString).forEach(result::add);
+        if (values.size() < size) {
+            for (int i = values.size(); i < size; i++) {
+                result.add(SparqlConstants.UNDEF);
+            }
+        }
+        return result;
+    }
+
+    @Override
+    public int valueCount() {
+        return values.size();
+    }
 }

jopa-impl/src/main/java/cz/cvut/kbss/jopa/query/parameter/ParameterValue.java

@@ -17,6 +17,11 @@
  */
 package cz.cvut.kbss.jopa.query.parameter;
 
+import cz.cvut.kbss.jopa.query.sparql.SparqlConstants;
+
+import java.util.ArrayList;
+import java.util.List;
+
 /**
  * Query parameter value holder.
  */
@@ -36,6 +41,31 @@ public interface ParameterValue {
      */
     String getQueryString();
 
+    /**
+     * Builds a list of the specified size containing the value(s) represented by this parameter value.
+     * <p>
+     * If this instance does not contain enough values to fill in the list of the specified size, its remainder is
+     * filled with {@link cz.cvut.kbss.jopa.query.sparql.SparqlConstants#UNDEF}s.
+     * <p>
+     * The resulting list will be used to build a SPARQL {@literal VALUES} table.
+     *
+     * @param size Requested size of value list
+     * @return List of values
+     */
+    default List<String> toQueryValues(int size) {
+        assert size > 0;
+
+        if (size == 1) {
+            return List.of(getQueryString());
+        }
+        final List<String> result = new ArrayList<>(size);
+        result.add(getQueryString());
+        for (int i = 1; i < size; i++) {
+            result.add(SparqlConstants.UNDEF);
+        }
+        return result;
+    }
+
     /**
      * Whether this parameter value is set or it represents just the parameter identification.
      *
@@ -44,4 +74,13 @@ public interface ParameterValue {
     default boolean isSet() {
         return true;
     }
+
+    /**
+     * Returns the number of values held by this instance.
+     * <p>
+     * Will return number different from 1 only for collection value parameters.
+     *
+     * @return Number of values represented by this instance
+     */
+    default int valueCount() {return 1;}
 }

jopa-impl/src/main/java/cz/cvut/kbss/jopa/query/sparql/SparqlConstants.java

@@ -37,6 +37,11 @@ public class SparqlConstants {
      */
     public static final String RDF_TYPE_SHORTCUT = "a";
 
+    /**
+     * The {@literal UNDEF} keyword.
+     */
+    public static final String UNDEF = "UNDEF";
+
     private SparqlConstants() {
         throw new AssertionError();
     }

jopa-impl/src/main/java/cz/cvut/kbss/jopa/query/sparql/SparqlQueryHolder.java

@@ -21,7 +21,15 @@
 import cz.cvut.kbss.jopa.query.QueryHolder;
 import cz.cvut.kbss.jopa.query.QueryParameter;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.Set;
 
 public class SparqlQueryHolder implements QueryHolder {
 
@@ -193,15 +201,32 @@ private static Optional<String> assembleValuesClause(Set<QueryParameter<?>> para
             return Optional.empty();
         }
         final StringBuilder variables = new StringBuilder();
-        final StringBuilder data = new StringBuilder();
+        final int tableSize = maxValueCount(parameters);
+        final List<List<String>> valueTable = new ArrayList<>(parameters.size());
         for (QueryParameter<?> qp : parameters) {
             if (!variables.isEmpty()) {
                 variables.append(' ');
             }
             variables.append(qp.getIdentifierAsQueryString());
-            data.append('(').append(qp.getValue().getQueryString()).append(')');
+            valueTable.add(qp.getValue().toQueryValues(tableSize));
         }
-        return Optional.of(" VALUES (" + variables + ") {" + data + "}");
+        return Optional.of(" VALUES (" + variables + ") { " + valueTableToString(valueTable, tableSize) + "}");
+    }
+
+    private static int maxValueCount(Set<QueryParameter<?>> parameters) {
+        return parameters.stream().map(p -> p.getValue().valueCount()).max(Integer::compareTo).orElse(1);
+    }
+
+    private static String valueTableToString(List<List<String>> valueTable, int rowSize) {
+        final StringBuilder sb = new StringBuilder();
+        for (int i = 0; i < rowSize; i++) {
+            sb.append("( ");
+            for (List<String> row : valueTable) {
+                sb.append(row.get(i)).append(" ");
+            }
+            sb.append(") ");
+        }
+        return sb.toString();
     }
 
     @Override

jopa-impl/src/test/java/cz/cvut/kbss/jopa/query/parameter/CollectionParameterValueTest.java

@@ -18,12 +18,16 @@
 package cz.cvut.kbss.jopa.query.parameter;
 
 import cz.cvut.kbss.jopa.environment.utils.Generators;
+import cz.cvut.kbss.jopa.query.sparql.SparqlConstants;
 import org.junit.jupiter.api.Test;
 
 import java.util.Arrays;
+import java.util.List;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.hasItems;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
 class CollectionParameterValueTest {
@@ -34,17 +38,35 @@ class CollectionParameterValueTest {
 
     @Test
     void getValueReturnsValuesOfIndividualElements() {
-        final CollectionParameterValue sut = new CollectionParameterValue(Arrays.asList(V_ONE, V_TWO, V_THREE));
+        final CollectionParameterValue sut = new CollectionParameterValue(List.of(V_ONE, V_TWO, V_THREE));
 
-        assertEquals(Arrays.asList(V_ONE.getValue(), V_TWO.getValue(), V_THREE.getValue()), sut.getValue());
+        assertEquals(List.of(V_ONE.getValue(), V_TWO.getValue(), V_THREE.getValue()), sut.getValue());
     }
 
     @Test
     void getQueryStringReturnsQueryStringRepresentationsOfIndividualElementsJoinedByComma() {
-        final CollectionParameterValue sut = new CollectionParameterValue(Arrays.asList(V_ONE, V_TWO, V_THREE));
+        final CollectionParameterValue sut = new CollectionParameterValue(List.of(V_ONE, V_TWO, V_THREE));
 
         assertEquals(
                 Stream.of(V_ONE, V_TWO, V_THREE).map(ParameterValue::getQueryString).collect(Collectors.joining(",")),
                 sut.getQueryString());
     }
+
+    @Test
+    void toQueryValuesReturnsListOfQueryStringifiedParameterValues() {
+        final CollectionParameterValue sut = new CollectionParameterValue(List.of(V_ONE, V_TWO, V_THREE));
+        final List<String> result = sut.toQueryValues(sut.valueCount());
+        assertEquals(Stream.of(V_ONE, V_TWO, V_THREE).map(ParameterValue::getQueryString).toList(), result);
+    }
+
+    @Test
+    void toQueryValuesReturnsListOfQueryStringifiedParameterValuesFilledWithSparqlUndefWhenSizeIsGreaterThanValueCount() {
+        final int size = 6;
+        final CollectionParameterValue sut = new CollectionParameterValue(List.of(V_ONE, V_TWO, V_THREE));
+        final List<String> result = sut.toQueryValues(size);
+        assertThat(result, hasItems(Stream.of(V_ONE, V_TWO, V_THREE).map(ParameterValue::getQueryString).toArray(String[]::new)));
+        final String[] remainder = new String[size - sut.valueCount()];
+        Arrays.fill(remainder, SparqlConstants.UNDEF);
+        assertThat(result, hasItems(remainder));
+    }
 }

jopa-impl/src/test/java/cz/cvut/kbss/jopa/query/parameter/ParameterValueTest.java

@@ -0,0 +1,29 @@
+package cz.cvut.kbss.jopa.query.parameter;
+
+import cz.cvut.kbss.jopa.environment.utils.Generators;
+import cz.cvut.kbss.jopa.query.sparql.SparqlConstants;
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class ParameterValueTest {
+
+    @Test
+    void toQueryValuesReturnsListOfSizeOneWithParameterValueStringifiedForQuery() {
+        final ParameterValue sut = new IntegerParameterValue(Generators.randomPositiveInt(1000));
+        final List<String> result = sut.toQueryValues(1);
+        assertEquals(List.of(sut.getQueryString()), result);
+    }
+
+    @Test
+    void toQueryValuesReturnsListOfSpecifiedSizeFilledWithValueAndUndef() {
+        final ParameterValue sut = new IntegerParameterValue(Generators.randomPositiveInt(1000));
+        int size = 5;
+        final List<String> result = sut.toQueryValues(size);
+        assertEquals(size, result.size());
+        assertEquals(sut.getQueryString(), result.get(0));
+        result.subList(1, size).forEach(v -> assertEquals(SparqlConstants.UNDEF, v));
+    }
+}

jopa-impl/src/test/java/cz/cvut/kbss/jopa/query/sparql/NamedParameterSparqlQueryHolderTest.java

@@ -36,14 +36,15 @@
 
 public class NamedParameterSparqlQueryHolderTest {
 
-    private static final String QUERY = "PREFIX foaf: <http://xmlns.com/foaf/0.1/>\n" +
-            "SELECT ?craft\n" +
-            "{\n" +
-            "?craft foaf:name \"Apollo 7\" .\n" +
-            "?craft foaf:homepage ?homepage .\n" +
-            "}";
+    private static final String QUERY = """
+            PREFIX foaf: <http://xmlns.com/foaf/0.1/>
+            SELECT ?craft
+            {
+              ?craft foaf:name "Apollo 7" .
+              ?craft foaf:homepage ?homepage .
+            }""";
     private static final List<String> PARTS = Arrays.asList("PREFIX foaf: <http://xmlns.com/foaf/0.1/>\n" +
-            "SELECT ", "\n{\n", " foaf:name \"Apollo 7\" .\n", " foaf:homepage ", " .\n}");
+            "SELECT ", "\n{\n  ", " foaf:name \"Apollo 7\" .\n  ", " foaf:homepage ", " .\n}");
     private static final List<String> PARAMS = Arrays.asList("craft", "craft", "craft", "homepage");
     private static final Set<String> PARAM_NAMES = new HashSet<>(Arrays.asList("craft", "homepage"));
 
@@ -103,7 +104,7 @@ public void getValueOfUnknownParameterThrowsIllegalArgumentException() {
 
     @Test
     public void testSetParameter() {
-        final String value = "http://kbss.felk.cvut.cz";
+        final String value = "https://kbss.felk.cvut.cz";
         holder.setParameter(new QueryParameter<>("homepage", paramValueFactory), value);
         assertEquals(value, holder.getParameterValue(holder.getParameter("homepage")));
     }
@@ -128,7 +129,7 @@ public void setUnknownParameterThrowsException() {
     @Test
     public void clearParameterRemovesParameterValue() {
         final QueryParameter<?> qp = new QueryParameter<>("homepage", paramValueFactory);
-        holder.setParameter(qp, URI.create("http://kbss.felk.cvut.cz"));
+        holder.setParameter(qp, URI.create("https://kbss.felk.cvut.cz"));
         assertNotNull(holder.getParameterValue(qp));
         holder.clearParameter(qp);
         assertNull(holder.getParameterValue(qp));
@@ -137,7 +138,7 @@ public void clearParameterRemovesParameterValue() {
     @Test
     public void clearParametersRemovesAllParameterValues() {
         final QueryParameter<?> qp = new QueryParameter<>("homepage", paramValueFactory);
-        holder.setParameter(qp, URI.create("http://kbss.felk.cvut.cz"));
+        holder.setParameter(qp, URI.create("https://kbss.felk.cvut.cz"));
         final QueryParameter<?> qpTwo = new QueryParameter<>("craft", paramValueFactory);
         holder.setParameter(qpTwo, "Programming");
         holder.getParameters().forEach(param -> assertNotNull(holder.getParameterValue(param)));
@@ -148,26 +149,28 @@ public void clearParametersRemovesAllParameterValues() {
     @Test
     public void assembleQueryWithUri() {
         final QueryParameter<?> qp = new QueryParameter<>("homepage", paramValueFactory);
-        holder.setParameter(qp, URI.create("http://kbss.felk.cvut.cz"));
-        final String expected = "PREFIX foaf: <http://xmlns.com/foaf/0.1/>\n" +
-                "SELECT ?craft\n" +
-                "{\n" +
-                "?craft foaf:name \"Apollo 7\" .\n" +
-                "?craft foaf:homepage <http://kbss.felk.cvut.cz> .\n" +
-                "}";
+        holder.setParameter(qp, URI.create("https://kbss.felk.cvut.cz"));
+        final String expected = """
+                PREFIX foaf: <http://xmlns.com/foaf/0.1/>
+                SELECT ?craft
+                {
+                  ?craft foaf:name "Apollo 7" .
+                  ?craft foaf:homepage <https://kbss.felk.cvut.cz> .
+                }""";
         assertEquals(expected, holder.assembleQuery());
     }
 
     @Test
     public void assembleQueryWithLiteral() {
         final QueryParameter<?> qp = new QueryParameter<>("homepage", paramValueFactory);
-        holder.setParameter(qp, "http://kbss.felk.cvut.cz", null);
-        final String expected = "PREFIX foaf: <http://xmlns.com/foaf/0.1/>\n" +
-                "SELECT ?craft\n" +
-                "{\n" +
-                "?craft foaf:name \"Apollo 7\" .\n" +
-                "?craft foaf:homepage \"http://kbss.felk.cvut.cz\" .\n" +
-                "}";
+        holder.setParameter(qp, "https://kbss.felk.cvut.cz", null);
+        final String expected = """
+                PREFIX foaf: <http://xmlns.com/foaf/0.1/>
+                SELECT ?craft
+                {
+                  ?craft foaf:name "Apollo 7" .
+                  ?craft foaf:homepage "https://kbss.felk.cvut.cz" .
+                }""";
         assertEquals(expected, holder.assembleQuery());
     }
 
@@ -192,10 +195,10 @@ public void setParametersAndAssembleQueryWithMultipleParamsNextToEachOther() {
     void setParameterAddsValuesClauseWhenSetParameterIsInProjection() {
         final QueryParameter<?> qp = new QueryParameter<>("craft", paramValueFactory);
         qp.setProjected(true);
-        holder.setParameter(qp, URI.create("http://kbss.felk.cvut.cz/apollo7"));
+        holder.setParameter(qp, URI.create("https://kbss.felk.cvut.cz/apollo7"));
         final String result = holder.assembleQuery();
-        assertThat(result, endsWith("VALUES (?craft) {(" + holder.getParameter("craft").getValue()
-                .getQueryString() + ")}"));
+        assertThat(result, endsWith("VALUES (?craft) { ( " + holder.getParameter("craft").getValue()
+                .getQueryString() + " ) }"));
         assertThat(result, containsString(QUERY));
     }
 }