SEAM-99

impl/pom.xml

@@ -29,6 +29,12 @@
             <scope>provided</scope>
         </dependency>
 
+        <!-- Require the servlet API because we define a filter -->
+	<dependency>
+	    <groupId>org.jboss.spec.javax.servlet</groupId>
+	    <artifactId>jboss-servlet-api_3.0_spec</artifactId>
+	</dependency>
+
         <dependency>
             <groupId>org.jboss.seam.transaction</groupId>
             <artifactId>seam-transaction-api</artifactId>

impl/src/main/java/org/jboss/seam/transaction/RollbackFilter.java

@@ -0,0 +1,69 @@
+package org.jboss.seam.transaction;
+
+import java.io.IOException;
+
+import javax.inject.Inject;
+import javax.servlet.Filter;
+import javax.servlet.FilterChain;
+import javax.servlet.FilterConfig;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+import javax.servlet.annotation.WebFilter;
+import javax.transaction.Status;
+import javax.transaction.SystemException;
+import javax.transaction.UserTransaction;
+
+/**
+ * This filter rolls back the current transaction if it is still active. 
+ * 
+ * @author Nicklas Karlsson
+ *
+ */
+@WebFilter(value = "/*")
+public class RollbackFilter implements Filter
+{
+    @Inject
+    private UserTransaction userTransaction;
+
+    @Override
+    public void destroy()
+    {
+    }
+
+    @Override
+    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException
+    {
+        try
+        {
+            rollbackTransactionIfActive();
+            chain.doFilter(request, response);
+        }
+        finally
+        {
+            rollbackTransactionIfActive();
+        }
+    }
+
+    private void rollbackTransactionIfActive()
+    {
+        try
+        {
+            if (userTransaction.getStatus() == Status.STATUS_ACTIVE)
+            {
+                userTransaction.rollback();
+            }
+        }
+        catch (SystemException e)
+        {
+            // so not?
+        }
+    }
+
+    @Override
+    public void init(FilterConfig config) throws ServletException
+    {
+    }
+
+}
+