[#219] Refactor all Handlers to derive from BaseRDFNodeHandler. Imple…

…ment tests.

s-pipes-core/src/main/java/cz/cvut/spipes/modules/handlers/BaseRdfNodeHandler.java → s-pipes-core/src/main/java/cz/cvut/spipes/modules/handlers/BaseRDFNodeHandler.java

@@ -8,30 +8,42 @@
 
 
 /**
- * Abstract Handler for cases when native Java value can be extracted directly from a single RDFNode.
+ * An abstract base class for handling RDF nodes and converting them to a specific type.
+ * This class provides a common implementation for handling RDF nodes and setting their values
+ * to fields of a specified type.
+ *
+ * @param <T> The type of the value that this handler converts RDF nodes to.
  */
-abstract public class BaseRdfNodeHandler<T>  extends Handler<T> {
+abstract public class BaseRDFNodeHandler<T>  extends Handler<T> {
 
-    public BaseRdfNodeHandler(Resource resource, ExecutionContext executionContext, Setter<? super T> setter) {
+    public BaseRDFNodeHandler(Resource resource, ExecutionContext executionContext, Setter<? super T> setter) {
         super(resource, executionContext, setter);
     }
 
     /**
-     * Constructs the native Java value from a given RDFNode.
+     * Converts an RDF node to a value of type {@code T}.
+     * This method must be implemented by subclasses to provide the specific conversion logic.
      *
-     * @param  node  the RDFNode to extract the native Java value from
-     * @return      the native Java value of the RDFNode
+     * @param node The RDF node to convert.
+     * @return The converted value of type {@code T}.
      */
-    abstract T getJavaNativeValue(RDFNode node);
+    abstract T getRDFNodeValue(RDFNode node) throws Exception;
 
+    /**
+     * Sets a value to the field associated with this handler by converting an RDF node
+     * retrieved from the specified RDF property.
+     *
+     * @param property The RDF property whose value is used to retrieve the RDF node.
+     * @throws ScriptRuntimeErrorException If an error occurs during the conversion or setting process.
+     */
     @Override
     public void setValueByProperty(Property property) {
         RDFNode node = getEffectiveValue(property);
 
         if (node != null) {
             try {
-                setter.addValue(getJavaNativeValue(node));
-            } catch (RuntimeException ex) {
+                setter.addValue(getRDFNodeValue(node));
+            } catch (Exception ex) {
                 throw new ScriptRuntimeErrorException(
                     String.format("""
                             Failed to set value of the field `%s` of type `%s` within class `%s`.

s-pipes-core/src/main/java/cz/cvut/spipes/modules/handlers/BooleanHandler.java

@@ -6,13 +6,13 @@
 import org.jetbrains.annotations.NotNull;
 
 
-public class BooleanHandler extends BaseRdfNodeHandler<Boolean> {
+public class BooleanHandler extends BaseRDFNodeHandler<Boolean> {
     public BooleanHandler(Resource resource, ExecutionContext executionContext, Setter<? super Boolean> setter) {
         super(resource, executionContext, setter);
     }
 
     @Override
-    Boolean getJavaNativeValue(@NotNull RDFNode node) {
+    Boolean getRDFNodeValue(@NotNull RDFNode node) {
         return node.asLiteral().getBoolean();
     }
 }

s-pipes-core/src/main/java/cz/cvut/spipes/modules/handlers/IntegerHandler.java

@@ -6,17 +6,15 @@
 import org.apache.jena.rdf.model.Resource;
 import org.apache.jena.rdf.model.Statement;
 
-public class IntegerHandler extends Handler<Integer>{
+public class IntegerHandler extends BaseRDFNodeHandler<Integer>{
 
     public IntegerHandler(Resource resource, ExecutionContext executionContext, Setter<? super Integer> setter) {
         super(resource, executionContext, setter);
     }
 
     @Override
-    public void setValueByProperty(Property property) {
-        RDFNode node = getEffectiveValue(property);
-        if (node != null && node.isLiteral()) {
-            setter.addValue(node.asLiteral().getInt());
-        }
+    Integer getRDFNodeValue(RDFNode node) {
+        return node.asLiteral().getInt();
     }
+
 }

s-pipes-core/src/main/java/cz/cvut/spipes/modules/handlers/PathHandler.java

@@ -8,17 +8,14 @@
 import java.nio.file.Paths;
 
 
-public class PathHandler extends Handler<Path> {
+public class PathHandler extends BaseRDFNodeHandler<Path> {
     public PathHandler(Resource resource, ExecutionContext executionContext, Setter<? super Path> setter) {
         super(resource, executionContext, setter);
     }
 
     @Override
-    public void setValueByProperty(Property property) {
-        RDFNode pathNode = getEffectiveValue(property);
-        if(pathNode != null) {
-            Path path = Paths.get(pathNode.toString());
-            setter.addValue(path);
-        }
+    Path getRDFNodeValue(RDFNode node) {
+        return Paths.get(node.toString());
     }
+
 }

s-pipes-core/src/main/java/cz/cvut/spipes/modules/handlers/RDFNodeHandler.java

@@ -5,16 +5,15 @@
 import org.apache.jena.rdf.model.RDFNode;
 import org.apache.jena.rdf.model.Resource;
 
-public class RDFNodeHandler extends Handler<RDFNode> {
+public class RDFNodeHandler extends BaseRDFNodeHandler<RDFNode> {
     public RDFNodeHandler(Resource resource, ExecutionContext executionContext, Setter<? super RDFNode> setter) {
         super(resource, executionContext, setter);
     }
 
     @Override
-    public void setValueByProperty(Property property) {
-        RDFNode node = getEffectiveValue(property);
-        if(node != null) {
-            setter.addValue(node);
-        }
+    RDFNode getRDFNodeValue(RDFNode node) {
+        return node;
     }
+
+
 }

s-pipes-core/src/main/java/cz/cvut/spipes/modules/handlers/ResourceHandler.java

@@ -6,17 +6,15 @@
 import org.apache.jena.rdf.model.RDFNode;
 import org.apache.jena.rdf.model.Resource;
 
-public class ResourceHandler extends Handler<Resource> {
+public class ResourceHandler extends BaseRDFNodeHandler<Resource> {
     public ResourceHandler(Resource resource, ExecutionContext executionContext, Setter<? super Resource> setter) {
         super(resource, executionContext, setter);
     }
 
     @Override
-    public void setValueByProperty(Property property) {
-        RDFNode node = getEffectiveValue(property);
-        if(node != null && node.isResource()) {
-            setter.addValue(node.asResource());
-        }
+    Resource getRDFNodeValue(RDFNode node) {
+        return node.asResource();
     }
+
 }
 

s-pipes-core/src/main/java/cz/cvut/spipes/modules/handlers/SelectHandler.java

@@ -7,17 +7,15 @@
 import org.apache.jena.rdf.model.Statement;
 import org.topbraid.spin.model.Select;
 
-public class SelectHandler extends Handler<Select> {
+public class SelectHandler extends BaseRDFNodeHandler<Select> {
 
     public SelectHandler(Resource resource, ExecutionContext executionContext, Setter<? super Select> setter) {
         super(resource, executionContext, setter);
     }
 
     @Override
-    public void setValueByProperty(Property property) {
-        RDFNode node = getEffectiveValue(property);
-        if (node != null) {
-            setter.addValue(node.asResource().as(Select.class));
-        }
+    Select getRDFNodeValue(RDFNode node) {
+        return node.asResource().as(Select.class);
     }
+
 }

s-pipes-core/src/main/java/cz/cvut/spipes/modules/handlers/StringHandler.java

@@ -5,18 +5,16 @@
 import org.apache.jena.rdf.model.RDFNode;
 import org.apache.jena.rdf.model.Resource;
 
-public class StringHandler extends Handler<String> {
+public class StringHandler extends BaseRDFNodeHandler<String> {
 
 
     public StringHandler(Resource resource, ExecutionContext executionContext, Setter<? super String> setter) {
         super(resource, executionContext, setter);
     }
 
     @Override
-    public void setValueByProperty(Property property) {
-        RDFNode node = getEffectiveValue(property);
-        if (node != null) {
-            setter.addValue(node.toString());
-        }
+    String getRDFNodeValue(RDFNode node) {
+        return node.toString();
     }
+
 }

s-pipes-core/src/main/java/cz/cvut/spipes/modules/handlers/URLHandler.java

@@ -6,24 +6,14 @@
 import java.net.MalformedURLException;
 import java.net.URL;
 
-public class URLHandler extends Handler<URL>{
+public class URLHandler extends BaseRDFNodeHandler<URL>{
     public URLHandler(Resource resource, ExecutionContext executionContext, Setter<? super URL> setter) {
         super(resource, executionContext, setter);
     }
 
     @Override
-    public void setValueByProperty(Property property) {
-        URL url;
-        RDFNode urlNode = getEffectiveValue(property);
-
-        if (urlNode != null) {
-            try {
-                url = new URL(urlNode.toString());
-                setter.addValue(url);
-            } catch (MalformedURLException e) {
-                throw new RuntimeException(e);
-            }
-        }
+    URL getRDFNodeValue(RDFNode node) throws MalformedURLException {
+        return new URL(node.toString());
     }
 
 }

s-pipes-core/src/test/java/cz/cvut/spipes/modules/handlers/BooleanHandlerTest.java

@@ -1,73 +1,43 @@
 package cz.cvut.spipes.modules.handlers;
 
-import static org.junit.jupiter.api.Assertions.*;
-import static org.mockito.Mockito.*;
-
 import cz.cvut.spipes.engine.ExecutionContext;
-import org.apache.jena.rdf.model.Literal;
-import org.apache.jena.rdf.model.Resource;
-import org.apache.jena.rdf.model.RDFNode;
-import org.apache.jena.rdf.model.Property;
+import cz.cvut.spipes.exception.ScriptRuntimeErrorException;
+import org.apache.jena.rdf.model.*;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
+import org.mockito.ArgumentCaptor;
 import org.mockito.Mockito;
 
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.Mockito.*;
+
 public class BooleanHandlerTest {
 
     private BooleanHandler booleanHandler;
-    private Resource resource;
-    private ExecutionContext executionContext;
-    private Setter<Boolean> setter;
-    private RDFNode rdfNode;
+    private Resource mockResource;
+    private ExecutionContext mockExecutionContext;
+    private Setter<Boolean> mockSetter;
 
     @BeforeEach
-    public void setUp() {
-        resource = mock(Resource.class);
-        executionContext = mock(ExecutionContext.class);
-        setter = mock(Setter.class);
-        booleanHandler = new BooleanHandler(resource, executionContext, setter);
+    void setUp() {
+        mockResource = mock(Resource.class);
+        mockExecutionContext = mock(ExecutionContext.class);
+        mockSetter = mock(Setter.class);
+        booleanHandler = new BooleanHandler(mockResource, mockExecutionContext, mockSetter);
     }
 
     @Test
-    public void testGetJavaNativeValueTrue() {
-        Literal literal = mock(Literal.class);
-        when(literal.getBoolean()).thenReturn(true);
-        rdfNode = mock(RDFNode.class);
-        when(rdfNode.asLiteral()).thenReturn(literal);
-
-        Boolean result = booleanHandler.getJavaNativeValue(rdfNode);
+    void testGetRDFNodeValueTrue() {
+        RDFNode rdfNode = ResourceFactory.createTypedLiteral(true);
+        Boolean result = booleanHandler.getRDFNodeValue(rdfNode);
         assertTrue(result);
     }
 
     @Test
-    public void testGetJavaNativeValueFalse() {
-        Literal literal = mock(Literal.class);
-        when(literal.getBoolean()).thenReturn(false);
-        rdfNode = mock(RDFNode.class);
-        when(rdfNode.asLiteral()).thenReturn(literal);
-
-        Boolean result = booleanHandler.getJavaNativeValue(rdfNode);
+    void testGetRDFNodeValueFalse() {
+        RDFNode rdfNode = ResourceFactory.createTypedLiteral(false);
+        Boolean result = booleanHandler.getRDFNodeValue(rdfNode);
         assertFalse(result);
     }
 
-    @Test
-    public void testGetJavaNativeValueInvalidType() {
-        Literal literal = mock(Literal.class);
-        when(literal.getBoolean()).thenThrow(new ClassCastException("Not a boolean"));
-        rdfNode = mock(RDFNode.class);
-        when(rdfNode.asLiteral()).thenReturn(literal);
-
-        assertThrows(ClassCastException.class, () -> booleanHandler.getJavaNativeValue(rdfNode));
-    }
-
-    @Test
-    public void testSetValueByPropertyNullNode() {
-        Property property = mock(Property.class);
-        when(booleanHandler.getEffectiveValue(property)).thenReturn(null);
-
-        booleanHandler.setValueByProperty(property);
-
-        verify(setter, never()).addValue(anyBoolean());
-    }
-
 }

s-pipes-core/src/test/java/cz/cvut/spipes/modules/handlers/IntegerHandlerTest.java

@@ -4,6 +4,8 @@
 import org.apache.jena.rdf.model.*;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.mockito.Mockito.*;
 
 public class IntegerHandlerTest {
@@ -12,53 +14,21 @@ public class IntegerHandlerTest {
     private Resource mockResource;
     private ExecutionContext mockExecutionContext;
     private Setter<Integer> mockSetter;
-    private Property mockProperty;
-    private Model model;
 
     @BeforeEach
-    public void setUp() {
+    void setUp() {
         mockResource = mock(Resource.class);
         mockExecutionContext = mock(ExecutionContext.class);
         mockSetter = mock(Setter.class);
-        mockProperty = mock(Property.class);
-        model = ModelFactory.createDefaultModel();
-
         integerHandler = new IntegerHandler(mockResource, mockExecutionContext, mockSetter);
     }
 
     @Test
-    public void testSetValueByPropertyWithIntegerLiteral() {
-        RDFNode integerLiteralNode = model.createLiteral(String.valueOf(42));
-        Statement mockStatement = mock(Statement.class);
-
-        when(mockResource.getProperty(mockProperty)).thenReturn(mockStatement);
-        when(mockStatement.getObject()).thenReturn(integerLiteralNode);
-
-        integerHandler.setValueByProperty(mockProperty);
-
-        verify(mockSetter).addValue(42);
-    }
-
-    @Test
-    public void testSetValueByPropertyWithNonLiteralNode() {
-        RDFNode nonLiteralNode = model.createResource();
-        Statement mockStatement = mock(Statement.class);
-
-        when(mockResource.getProperty(mockProperty)).thenReturn(mockStatement);
-        when(mockStatement.getObject()).thenReturn(nonLiteralNode);
-
-        integerHandler.setValueByProperty(mockProperty);
-
-        verify(mockSetter, never()).addValue(anyInt());
-    }
-
-    @Test
-    public void testSetValueByPropertyWithNullNode() {
-
-        when(mockResource.getProperty(mockProperty)).thenReturn(null);
+    void testGetRDFNodeValue() {
+        RDFNode rdfNode = ResourceFactory.createTypedLiteral(42);
 
-        integerHandler.setValueByProperty(mockProperty);
+        Integer result = integerHandler.getRDFNodeValue(rdfNode);
 
-        verify(mockSetter, never()).addValue(anyInt());
+        assertEquals(Integer.valueOf(42), result);
     }
 }