spider: address memory leak

addOns/spider/CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 - Handle persistence errors and forced shutdown in automation job.
+- Address memory leak.
 
 ## [0.18.0] - 2025-12-15
 ### Changed

addOns/spider/src/main/java/org/zaproxy/addon/spider/SpiderTask.java

@@ -76,14 +76,13 @@ public class SpiderTask implements Runnable {
      */
     private HistoryReference reference;
 
-    /** The spider resource found. */
-    private SpiderResourceFound resourceFound;
-
     private ExtensionHistory extHistory;
 
     /** The Constant log. */
     private static final Logger LOGGER = LogManager.getLogger(SpiderTask.class);
 
+    private final int depth;
+
     /**
      * Instantiates a new spider task using the target URI. The purpose of this task is to crawl the
      * given uri, using the provided method and supplied request headers, find any other uris in the
@@ -99,7 +98,7 @@ public class SpiderTask implements Runnable {
     public SpiderTask(Spider parent, SpiderResourceFound resourceFound, URI uri) {
         super();
         this.parent = parent;
-        this.resourceFound = resourceFound;
+        this.depth = resourceFound.getDepth();
 
         LOGGER.debug("New task submitted for uri: {}", uri);
 
@@ -151,7 +150,7 @@ public void run() {
 
             LOGGER.debug(
                     "Spider Task Started. Processing uri at depth {} using already constructed message: {}",
-                    resourceFound.getDepth(),
+                    depth,
                     reference.getURI());
 
             runImpl();
@@ -234,9 +233,9 @@ private void runImpl() {
         parent.checkPauseAndWait();
 
         int maxDepth = parent.getSpiderParam().getMaxDepth();
-        if (maxDepth == SpiderParam.UNLIMITED_DEPTH || resourceFound.getDepth() < maxDepth) {
+        if (maxDepth == SpiderParam.UNLIMITED_DEPTH || depth < maxDepth) {
             parent.notifyListenersSpiderTaskResult(new SpiderTaskResult(msg));
-            processResource(parent, resourceFound.getDepth(), msg);
+            processResource(parent, depth, msg);
         } else {
             parent.notifyListenersSpiderTaskResult(
                     new SpiderTaskResult(msg, getSkippedMessage("maxdepth")));