From bbb67b1d8d1b323be56fd54eafc5bafcec05f4cc Mon Sep 17 00:00:00 2001
From: bern-SOPTIM <arne.bernhardt@soptim.de>
Date: Tue, 30 Dec 2025 16:21:41 +0100
Subject: [PATCH] GH-3844: Using JEP 394: Pattern Matching for instanceof for
 #equals in Node and Triple implementations

- Using JEP 394: Pattern Matching for instanceof for #equals in Node and Triple implementations
---
 jena-core/src/main/java/org/apache/jena/graph/Node_ANY.java  | 4 +---
 .../src/main/java/org/apache/jena/graph/Node_Blank.java      | 5 +----
 jena-core/src/main/java/org/apache/jena/graph/Node_Ext.java  | 5 +----
 .../src/main/java/org/apache/jena/graph/Node_Graph.java      | 3 +--
 .../src/main/java/org/apache/jena/graph/Node_Literal.java    | 5 +----
 .../src/main/java/org/apache/jena/graph/Node_Triple.java     | 5 +----
 jena-core/src/main/java/org/apache/jena/graph/Node_URI.java  | 5 +----
 .../src/main/java/org/apache/jena/graph/Node_Variable.java   | 5 +----
 jena-core/src/main/java/org/apache/jena/graph/Triple.java    | 2 +-
 9 files changed, 9 insertions(+), 30 deletions(-)

diff --git a/jena-core/src/main/java/org/apache/jena/graph/Node_ANY.java b/jena-core/src/main/java/org/apache/jena/graph/Node_ANY.java
index daf135099b7..0d54f46ad3f 100644
--- a/jena-core/src/main/java/org/apache/jena/graph/Node_ANY.java
+++ b/jena-core/src/main/java/org/apache/jena/graph/Node_ANY.java
@@ -45,9 +45,7 @@ public int hashCode() {
     @Override
     public boolean equals(Object other) {
         // There is only one such object.
-        if ( this == other )
-            return true;
-        return false;
+        return this == other;
     }
 
     @Override
diff --git a/jena-core/src/main/java/org/apache/jena/graph/Node_Blank.java b/jena-core/src/main/java/org/apache/jena/graph/Node_Blank.java
index 7495ccedd1a..79c89ba6e29 100644
--- a/jena-core/src/main/java/org/apache/jena/graph/Node_Blank.java
+++ b/jena-core/src/main/java/org/apache/jena/graph/Node_Blank.java
@@ -58,11 +58,8 @@ public int hashCode() {
     public boolean equals(Object obj) {
         if ( this == obj )
             return true;
-        if ( obj == null )
+        if ( !(obj instanceof Node_Blank other) )
             return false;
-        if ( getClass() != obj.getClass() )
-            return false;
-        Node_Blank other = (Node_Blank)obj;
         return Objects.equals(label, other.label);
     }
 
diff --git a/jena-core/src/main/java/org/apache/jena/graph/Node_Ext.java b/jena-core/src/main/java/org/apache/jena/graph/Node_Ext.java
index 2175e079913..ca9f5a137c3 100644
--- a/jena-core/src/main/java/org/apache/jena/graph/Node_Ext.java
+++ b/jena-core/src/main/java/org/apache/jena/graph/Node_Ext.java
@@ -71,11 +71,8 @@ public int hashCode() {
     public boolean equals(Object obj) {
         if ( this == obj )
             return true;
-        if ( obj == null )
+        if ( !( obj instanceof Node_Ext<?> other ) )
             return false;
-        if ( getClass() != obj.getClass() )
-            return false;
-        Node_Ext<?> other = (Node_Ext<?>)obj;
         return Objects.equals(object, other.object);
     }
 }
diff --git a/jena-core/src/main/java/org/apache/jena/graph/Node_Graph.java b/jena-core/src/main/java/org/apache/jena/graph/Node_Graph.java
index b51626913c7..3cf7b0b0d9a 100644
--- a/jena-core/src/main/java/org/apache/jena/graph/Node_Graph.java
+++ b/jena-core/src/main/java/org/apache/jena/graph/Node_Graph.java
@@ -67,9 +67,8 @@ public int hashCode() {
     public boolean equals(Object o) {
         if ( o == this )
             return true;
-        if ( !(o instanceof Node_Graph) )
+        if ( !(o instanceof Node_Graph other) )
             return false;
-        Node_Graph other = (Node_Graph)o;
         return this.getGraph() == other.getGraph();
     }
 
diff --git a/jena-core/src/main/java/org/apache/jena/graph/Node_Literal.java b/jena-core/src/main/java/org/apache/jena/graph/Node_Literal.java
index 202254f63b5..61fdaa58dae 100644
--- a/jena-core/src/main/java/org/apache/jena/graph/Node_Literal.java
+++ b/jena-core/src/main/java/org/apache/jena/graph/Node_Literal.java
@@ -120,11 +120,8 @@ public int hashCode()
     public boolean equals(Object obj) {
         if ( this == obj )
             return true;
-        if ( obj == null )
+        if ( !( obj instanceof Node_Literal other ) )
             return false;
-        if ( getClass() != obj.getClass() )
-            return false;
-        Node_Literal other = (Node_Literal)obj;
         return label.equals(other.label);
     }
 
diff --git a/jena-core/src/main/java/org/apache/jena/graph/Node_Triple.java b/jena-core/src/main/java/org/apache/jena/graph/Node_Triple.java
index 864bafe36bc..77c81b067a1 100644
--- a/jena-core/src/main/java/org/apache/jena/graph/Node_Triple.java
+++ b/jena-core/src/main/java/org/apache/jena/graph/Node_Triple.java
@@ -68,11 +68,8 @@ public int hashCode() {
     public boolean equals(Object obj) {
         if ( this == obj )
             return true;
-        if ( obj == null )
+        if ( !( obj instanceof Node_Triple other ) )
             return false;
-        if ( getClass() != obj.getClass() )
-            return false;
-        Node_Triple other = (Node_Triple)obj;
         return triple.equals(other.triple);
     }
 
diff --git a/jena-core/src/main/java/org/apache/jena/graph/Node_URI.java b/jena-core/src/main/java/org/apache/jena/graph/Node_URI.java
index dbf1f5b11b3..ce6626ceee0 100644
--- a/jena-core/src/main/java/org/apache/jena/graph/Node_URI.java
+++ b/jena-core/src/main/java/org/apache/jena/graph/Node_URI.java
@@ -98,11 +98,8 @@ public int hashCode() {
     public boolean equals(Object obj) {
         if ( this == obj )
             return true;
-        if ( obj == null )
+        if ( !( obj instanceof Node_URI other ) )
             return false;
-        if ( getClass() != obj.getClass() )
-            return false;
-        Node_URI other = (Node_URI)obj;
         return uriStr.equals(other.uriStr);
     }
 }
diff --git a/jena-core/src/main/java/org/apache/jena/graph/Node_Variable.java b/jena-core/src/main/java/org/apache/jena/graph/Node_Variable.java
index efa7211addf..12cc7cbda9d 100644
--- a/jena-core/src/main/java/org/apache/jena/graph/Node_Variable.java
+++ b/jena-core/src/main/java/org/apache/jena/graph/Node_Variable.java
@@ -66,12 +66,9 @@ public int hashCode() {
     public boolean equals(Object obj) {
         if ( this == obj )
             return true;
-        if ( obj == null )
-            return false;
         // For jena-arq Var
-        if ( ! (obj instanceof Node_Variable) )
+        if ( ! (obj instanceof Node_Variable other) )
             return false;
-        Node_Variable other = (Node_Variable)obj;
         return Objects.equals(varName, other.varName);
     }
 
diff --git a/jena-core/src/main/java/org/apache/jena/graph/Triple.java b/jena-core/src/main/java/org/apache/jena/graph/Triple.java
index 3242aef877e..2ebd08f37aa 100644
--- a/jena-core/src/main/java/org/apache/jena/graph/Triple.java
+++ b/jena-core/src/main/java/org/apache/jena/graph/Triple.java
@@ -156,7 +156,7 @@ public boolean isConcrete()
      */
 	@Override
     public boolean equals(Object o)
-	{ return o instanceof Triple && ((Triple) o).sameAs( subj, pred, obj ); }
+	{ return o instanceof Triple t && t.sameAs( subj, pred, obj ); }
 
     /**
         Answer true iff this triple has subject s, predicate p, and object o.