From 9199f0d66be476789e073ea96571fa4017269896 Mon Sep 17 00:00:00 2001
From: mishako <mishako@users.noreply.github.com>
Date: Fri, 15 Jul 2016 22:18:29 +0200
Subject: [PATCH] Clean up threadlocal after usage

ThreadLocal is not guaranteed to be garbage collected if the thread
keeps running. This can lead to a memory leak in applications with
long-living threads.

Fixes #303
---
 .../rome/feed/impl/ToStringBean.java          | 31 +++++++++++--------
 1 file changed, 18 insertions(+), 13 deletions(-)

diff --git a/rome/src/main/java/com/rometools/rome/feed/impl/ToStringBean.java b/rome/src/main/java/com/rometools/rome/feed/impl/ToStringBean.java
index d1ec50d..817fd0c 100644
--- a/rome/src/main/java/com/rometools/rome/feed/impl/ToStringBean.java
+++ b/rome/src/main/java/com/rometools/rome/feed/impl/ToStringBean.java
@@ -41,17 +41,7 @@ public class ToStringBean implements Serializable {
     private static final long serialVersionUID = 1L;
     private static final Logger LOG = LoggerFactory.getLogger(ToStringBean.class);
 
-    private static final ThreadLocal<Stack<String[]>> PREFIX_TL = new ThreadLocal<Stack<String[]>>() {
-        @Override
-        public Stack<String[]> get() {
-            Stack<String[]> o = super.get();
-            if (o == null) {
-                o = new Stack<String[]>();
-                set(o);
-            }
-            return o;
-        }
-    };
+    private static final ThreadLocal<Stack<String[]>> PREFIX_TL = new ThreadLocal<Stack<String[]>>();
 
     private static final Object[] NO_PARAMS = new Object[0];
 
@@ -113,7 +103,15 @@ public class ToStringBean implements Serializable {
      */
     @Override
     public String toString() {
-        final Stack<String[]> stack = PREFIX_TL.get();
+        Stack<String[]> stack = PREFIX_TL.get();
+        boolean needStackCleanup = false;
+
+        if (stack == null) {
+            stack = new Stack<String[]>();
+            PREFIX_TL.set(stack);
+            needStackCleanup = true;
+        }
+
         final String[] tsInfo;
         if (stack.isEmpty()) {
             tsInfo = null;
@@ -128,7 +126,14 @@ public class ToStringBean implements Serializable {
             prefix = tsInfo[0];
             tsInfo[1] = prefix;
         }
-        return this.toString(prefix);
+
+        final String result = toString(prefix);
+
+        if (needStackCleanup) {
+          PREFIX_TL.remove();
+        }
+
+        return result;
     }
 
     /**