diff --git a/core/src/main/java/com/opensymphony/xwork2/util/fs/JarEntryRevision.java b/core/src/main/java/com/opensymphony/xwork2/util/fs/JarEntryRevision.java
index 4b962af08d..268710fb83 100644
--- a/core/src/main/java/com/opensymphony/xwork2/util/fs/JarEntryRevision.java
+++ b/core/src/main/java/com/opensymphony/xwork2/util/fs/JarEntryRevision.java
@@ -3,12 +3,10 @@
 import com.opensymphony.xwork2.FileManager;
 import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.LogManager;
-import org.apache.commons.io.FileUtils;
 
 import java.io.IOException;
+import java.net.JarURLConnection;
 import java.net.URL;
-import java.util.jar.JarFile;
-import java.util.zip.ZipEntry;
 
 /**
  * Represents jar resource revision, used for jar://* resource
@@ -17,66 +15,63 @@ public class JarEntryRevision extends Revision {
 
     private static Logger LOG = LogManager.getLogger(JarEntryRevision.class);
 
-    private static final String JAR_FILE_NAME_SEPARATOR = "!/";
-    private static final String JAR_FILE_EXTENSION_END = ".jar/";
-
-    private String jarFileName;
-    private String fileNameInJar;
+    private URL jarFileURL;
     private long lastModified;
 
     public static Revision build(URL fileUrl, FileManager fileManager) {
         // File within a Jar
         // Find separator index of jar filename and filename within jar
-        String jarFileName = "";
+        JarURLConnection conn = null;
         try {
-            String fileName = fileUrl.toString();
-            int separatorIndex = fileName.indexOf(JAR_FILE_NAME_SEPARATOR);
-            if (separatorIndex == -1) {
-                separatorIndex = fileName.lastIndexOf(JAR_FILE_EXTENSION_END);
-            }
-            if (separatorIndex == -1) {
-                LOG.warn("Could not find end of jar file!");
-                return null;
-            }
-
-            // Split file name
-            jarFileName = fileName.substring(0, separatorIndex);
-            int index = separatorIndex + JAR_FILE_NAME_SEPARATOR.length();
-            String fileNameInJar = fileName.substring(index).replaceAll("%20", " ");
-
+            conn = (JarURLConnection) fileUrl.openConnection();
+            conn.setUseCaches(false);
             URL url = fileManager.normalizeToFileProtocol(fileUrl);
             if (url != null) {
-                JarFile jarFile = new JarFile(FileUtils.toFile(url));
-                ZipEntry entry = jarFile.getEntry(fileNameInJar);
-                return new JarEntryRevision(jarFileName, fileNameInJar, entry.getTime());
+                return new JarEntryRevision(fileUrl, conn.getJarEntry().getTime());
             } else {
                 return null;
             }
         } catch (Throwable e) {
-            LOG.warn("Could not create JarEntryRevision for [{}]!", jarFileName, e);
+            LOG.warn("Could not create JarEntryRevision for [{}]!", fileUrl, e);
             return null;
         }
+        finally {
+            if(null != conn) {
+                try {
+                    conn.getInputStream().close();
+                } catch (IOException ignored) {
+                }
+            }
+        }
     }
 
-    private JarEntryRevision(String jarFileName, String fileNameInJar, long lastModified) {
-        if ((jarFileName == null) || (fileNameInJar == null)) {
-            throw new IllegalArgumentException("JarFileName and FileNameInJar cannot be null");
+    private JarEntryRevision(URL jarFileURL, long lastModified) {
+        if (jarFileURL == null) {
+            throw new IllegalArgumentException("jarFileURL cannot be null");
         }
-        this.jarFileName = jarFileName;
-        this.fileNameInJar = fileNameInJar;
+        this.jarFileURL = jarFileURL;
         this.lastModified = lastModified;
     }
 
     public boolean needsReloading() {
-        ZipEntry entry;
+        JarURLConnection conn = null;
+        long lastLastModified = lastModified;
         try {
-            JarFile jarFile = new JarFile(this.jarFileName);
-            entry = jarFile.getEntry(this.fileNameInJar);
-        } catch (IOException e) {
-            entry = null;
+            conn = (JarURLConnection) jarFileURL.openConnection();
+            conn.setUseCaches(false);
+            lastLastModified = conn.getJarEntry().getTime();
+        } catch (IOException ignored) {
+        }
+        finally {
+            if(null != conn) {
+                try {
+                    conn.getInputStream().close();
+                } catch (IOException ignored) {
+                }
+            }
         }
 
-        return entry != null && (lastModified < entry.getTime());
+        return lastModified < lastLastModified;
     }
 
 }
diff --git a/core/src/test/java/com/opensymphony/xwork2/util/fs/JarEntryRevisionTest.java b/core/src/test/java/com/opensymphony/xwork2/util/fs/JarEntryRevisionTest.java
new file mode 100644
index 0000000000..04826d502d
--- /dev/null
+++ b/core/src/test/java/com/opensymphony/xwork2/util/fs/JarEntryRevisionTest.java
@@ -0,0 +1,54 @@
+package com.opensymphony.xwork2.util.fs;
+
+import com.opensymphony.xwork2.FileManager;
+import com.opensymphony.xwork2.FileManagerFactory;
+import com.opensymphony.xwork2.XWorkTestCase;
+import org.apache.commons.io.IOUtils;
+
+import java.io.FileOutputStream;
+import java.io.InputStream;
+import java.net.URL;
+import java.util.jar.Attributes;
+import java.util.jar.JarOutputStream;
+import java.util.jar.Manifest;
+import java.util.zip.ZipEntry;
+
+public class JarEntryRevisionTest extends XWorkTestCase {
+
+    private FileManager fileManager;
+
+    @Override
+    public void setUp() throws Exception {
+        super.setUp();
+        fileManager = container.getInstance(FileManagerFactory.class).getFileManager();
+    }
+
+    private void createJarFile(long time) throws Exception {
+        Manifest manifest = new Manifest();
+        manifest.getMainAttributes().put(Attributes.Name.MANIFEST_VERSION, "1.0");
+        FileOutputStream fos = new FileOutputStream("target/JarEntryRevisionTest_testNeedsReloading.jar", false);
+        JarOutputStream target = new JarOutputStream(fos, manifest);
+        target.putNextEntry(new ZipEntry("com/opensymphony/xwork2/util/fs/"));
+        ZipEntry entry = new ZipEntry("com/opensymphony/xwork2/util/fs/JarEntryRevisionTest.class");
+        entry.setTime(time);
+        target.putNextEntry(entry);
+        InputStream source = getClass().getResourceAsStream("/com/opensymphony/xwork2/util/fs/JarEntryRevisionTest.class");
+        IOUtils.copy(source, target);
+        source.close();
+        target.closeEntry();
+        target.close();
+        fos.close();
+    }
+
+    public void testNeedsReloading() throws Exception {
+        long now = System.currentTimeMillis();
+
+        createJarFile(now);
+        URL url = new URL("jar:file:target/JarEntryRevisionTest_testNeedsReloading.jar!/com/opensymphony/xwork2/util/fs/JarEntryRevisionTest.class");
+        Revision entry = JarEntryRevision.build(url, fileManager);
+        assertFalse(entry.needsReloading());
+
+        createJarFile(now + 60000);
+        assertTrue(entry.needsReloading());
+    }
+}