PDFBOX-4472: avoid deadlock, as suggested by Arnaud Jeansen
diff --git a/src/main/java/org/apache/pdfbox/jbig2/util/cache/SoftReferenceCache.java b/src/main/java/org/apache/pdfbox/jbig2/util/cache/SoftReferenceCache.java
index 9ad7027..497a9f1 100644
--- a/src/main/java/org/apache/pdfbox/jbig2/util/cache/SoftReferenceCache.java
+++ b/src/main/java/org/apache/pdfbox/jbig2/util/cache/SoftReferenceCache.java
@@ -18,13 +18,14 @@
package org.apache.pdfbox.jbig2.util.cache;
import java.lang.ref.SoftReference;
+import java.util.Collections;
import java.util.Map;
import java.util.WeakHashMap;
public class SoftReferenceCache implements Cache
{
-
- private final Map<Object, SoftReference<?>> cache = new WeakHashMap<Object, SoftReference<?>>();
+ private final Map<Object, SoftReference<?>> cache =
+ Collections.synchronizedMap(new WeakHashMap<Object, SoftReference<?>>());
@Override
public Object put(Object key, Object value, int sizeEstimate)
