Implement #1981: ContainerNode.remove(JsonPointer) (#5428)

Author: cowtowncoder

release-notes/VERSION

@@ -10,6 +10,8 @@ Versions: 3.x (for earlier see VERSION-2.x)
 #1196: Add opt-in error collection for deserialization
  (requested by @odrotbohm)
  (contributed by @sri-adarsh-kumar)
+#1980: Add method `remove(JsonPointer)` in `ContainerNode`
+ (fix by @cowtowncoder, w/ Claude code)
 #5350: Add `DeserializationFeature.USE_NULL_FOR_MISSING_REFERENCE_VALUES` for
   selecting `null` vs "empty/absent" value when deserializing missing `Optional` value
 #5361: Fix Maven SBOM publishing (worked in 3.0.0-rc4 but not in rc5 or later)

src/main/java/tools/jackson/databind/node/ArrayNode.java

@@ -60,6 +60,12 @@ protected JsonNode _at(JsonPointer ptr) {
         return get(ptr.getMatchingIndex());
     }
 
+    @Override // @since 3.1
+    protected JsonNode _removeAt(JsonPointer ptr) {
+        JsonNode n = remove(ptr.getMatchingIndex());
+        return (n == null) ? missingNode() : n;
+    }
+
     @Override
     protected String _valueDesc() {
         return "[...(" + _children.size() + " elements)]";

src/main/java/tools/jackson/databind/node/ContainerNode.java

@@ -201,4 +201,86 @@ public final NumericNode numberNode(long v) {
     public T removeNulls() {
         return removeIf(JsonNode::isNull);
     }
+
+    /*
+    /**********************************************************************
+    /* JsonPointer-based removal (3.1)
+    /**********************************************************************
+     */
+
+    /**
+     * Method for removing the child node pointed to by given {@link JsonPointer},
+     * if such a node exists.
+     *<p>
+     * For example, given JSON document:
+     *<pre>
+     *  {
+     *    "a" : {
+     *      "b" : {
+     *        "c" : 13
+     *      }
+     *    }
+     *  }
+     *</pre>
+     * calling {@code remove(JsonPointer.compile("/a/b/c"))} would remove the
+     * numeric value {@code 13}, resulting in:
+     *<pre>
+     *  {
+     *    "a" : {
+     *      "b" : { }
+     *    }
+     *  }
+     *</pre>
+     *<p>
+     * If the pointer points to a missing node, nothing is removed and {@code null}
+     * is returned.
+     *
+     * @param ptr Pointer to the node to remove
+     *
+     * @return The removed node, if it existed; {@link MissingNode} if no node was found
+     *   at the specified path
+     *
+     * @since 3.1
+     */
+    public JsonNode remove(JsonPointer ptr) {
+        // Empty pointer would mean remove this node, but that doesn't make sense
+        // as we can't remove ourselves from parent context
+        if (ptr.matches()) {
+            return missingNode();
+        }
+
+        // Navigate to the parent of the target node
+        ContainerNode<?> parent = this;
+        JsonPointer currentPtr = ptr;
+
+        // Keep navigating until we're at the parent of the target
+        while (true) {
+            JsonPointer tail = currentPtr.tail();
+
+            // If tail is empty, we're at the parent - remove from here
+            if (tail.matches()) {
+                return parent._removeAt(currentPtr);
+            }
+
+            // Otherwise, navigate one level deeper
+            JsonNode next = parent._at(currentPtr);
+            if (next instanceof ContainerNode<?> cn) {
+                parent = cn;
+            } else {
+                return missingNode();
+            }
+
+            currentPtr = tail;
+        }
+    }
+
+    /**
+     * Internal helper method for removing a node at the current (single-segment)
+     * pointer location.
+     *
+     * @param ptr Pointer with single segment to remove
+     *
+     * @return The removed node, if it existed; {@link #missingNode()} if not found
+     */
+    protected abstract JsonNode _removeAt(JsonPointer ptr);
 }

src/main/java/tools/jackson/databind/node/ObjectNode.java

@@ -56,6 +56,12 @@ protected JsonNode _at(JsonPointer ptr) {
         return get(ptr.getMatchingProperty());
     }
 
+    @Override // @since 3.1
+    protected JsonNode _removeAt(JsonPointer ptr) {
+        JsonNode n = remove(ptr.getMatchingProperty());
+        return (n == null) ? missingNode() : n;
+    }
+
     @Override
     protected String _valueDesc() {
         return "{...(" + _children.size() + " properties}]";
@@ -447,7 +453,6 @@ public List<JsonNode> findParents(String propertyName, List<JsonNode> foundSoFar
      * Method that can be called to serialize this node and
      * all of its descendants using specified JSON generator.
      */
-    @SuppressWarnings("deprecation")
     @Override
     public void serialize(JsonGenerator g, SerializationContext ctxt)
         throws JacksonException
@@ -479,7 +484,6 @@ public void serialize(JsonGenerator g, SerializationContext ctxt)
         g.writeEndObject();
     }
 
-    @SuppressWarnings("deprecation")
     @Override
     public void serializeWithType(JsonGenerator g, SerializationContext ctxt,
             TypeSerializer typeSer)