Bug 66521: Add a utility to clear all thread locals

Otherwise some applications may complain about left-over things,
e.g. Tomcat sometimes reports warning logs if Threads are not
cleaned up before being passed back into the global thread-pool.

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1908263 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 5 insertions, 0 deletions

diff --git a/poi-scratchpad/src/main/java/org/apache/poi/hslf/usermodel/HSLFSlideShow.java b/poi-scratchpad/src/main/java/org/apache/poi/hslf/usermodel/HSLFSlideShow.java
index 54438d7bb7..1447eab4b1 100644
--- a/poi-scratchpad/src/main/java/org/apache/poi/hslf/usermodel/HSLFSlideShow.java
+++ b/poi-scratchpad/src/main/java/org/apache/poi/hslf/usermodel/HSLFSlideShow.java
@@ -66,6 +66,7 @@ import org.apache.poi.sl.usermodel.SlideShow;
 import org.apache.poi.util.GenericRecordUtil;
 import org.apache.poi.util.IOUtils;
 import org.apache.poi.util.Internal;
+import org.apache.poi.util.ThreadLocalUtil;
 import org.apache.poi.util.Units;
 
 /**
@@ -92,6 +93,10 @@ public final class HSLFSlideShow extends POIDocument implements SlideShow<HSLFSh
         INIT, LOADED
     }
     private static final ThreadLocal<LoadSavePhase> loadSavePhase = new ThreadLocal<>();
+    static {
+        // allow to clear all thread-locals via ThreadLocalUtil
+        ThreadLocalUtil.registerCleaner(loadSavePhase::remove);
+    }
 
     // What we're based on
     private final HSLFSlideShowImpl _hslfSlideShow;