diff --git a/.hgignore b/.hgignore
index 3fadd4c..1364052 100644
--- a/.hgignore
+++ b/.hgignore
@@ -21,6 +21,7 @@ foundation_pEp_jniadapter_Engine.*
 foundation_pEp_jniadapter_Message.*
 foundation_pEp_jniadapter_Identity.h
 throw_pEp_exception.*
+src/java/foundation/pEp/jniadapter/exceptions/*.java
 
 CipherSuite.java
 Color.java
@@ -30,7 +31,6 @@ EngineInterface.java
 IdentityFlags.java
 Message.java
 MessageInterface.java
-pEp*.java
 Rating.java
 Status.java
 SyncHandshakeResult.java
diff --git a/src/Makefile b/src/Makefile
index 9f479e6..bba68cc 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -67,7 +67,8 @@ GENERATED_JAVA=\
 	$(JAVA_PKG_ROOT)/SyncHandshakeResult.java \
 	$(JAVA_PKG_ROOT)/SyncHandshakeSignal.java \
 	$(JAVA_PKG_ROOT)/interfaces/EngineInterface.java \
- 	$(JAVA_PKG_ROOT)/interfaces/MessageInterface.java
+ 	$(JAVA_PKG_ROOT)/interfaces/MessageInterface.java \
+ 	$(JAVA_PKG_ROOT)/exceptions/*.java
 
 # files to compile which will be be generated
 GENERATED_CC=\
@@ -159,6 +160,7 @@ create-dirs:
 	mkdir -p $(JAVA_BUILD_ROOT)/$(JAVA_PKG_BASENAME)/exceptions
 	mkdir -p $(OBJ_DIR)
 	mkdir -p $(DIST_DIR)
+	mkdir -p $(JAVA_PKG_ROOT)/exceptions
 
 #rm -rf is too dangerous for vars
 remove-dirs:
diff --git a/src/codegen/Makefile b/src/codegen/Makefile
index 907426c..16ca8bd 100644
--- a/src/codegen/Makefile
+++ b/src/codegen/Makefile
@@ -9,9 +9,9 @@ MARKER_DIR=../../build/marker/
 
 PEP_HEADER:=$(shell $(CXX) $(CXXFLAGS) -E -M ../cxx/get_header.cc | grep -oe '[^[:space:]]*pEpEngine\.h' | head -1)
 
-# Every ysl2 file that need to be "compiled" separately, needs to generate a "marker" file
+# Every ysl2 file that needs to be "compiled" separately, needs to generate a "marker" file
 # The marker serves as the make target.
-# If the marker file is older than its corresponding ysl2 file, or not exsiting the ysl2 file will be "compiled"
+# If the marker file is older than its corresponding ysl2 file, or not exsiting, the ysl2 file will be "compiled"
 # Naming:
 # For a ysl2 file called "gen_example_stuff.ysl2", a marker file called "gen_example_stuff.marker" is expected.
 YML2_MARKERS= \
diff --git a/src/codegen/gen_java_Message.ysl2 b/src/codegen/gen_java_Message.ysl2
index 04224e1..7007f6f 100644
--- a/src/codegen/gen_java_Message.ysl2
+++ b/src/codegen/gen_java_Message.ysl2
@@ -6,6 +6,17 @@ tstylesheet {
 
     template "/namespace[@name='pEp']" {
         apply "struct|enum|exception", 0;
+        document "../java/foundation/pEp/jniadapter/exceptions/pEpException.java", "text" {
+            ||
+            package foundation.pEp.jniadapter.exceptions;
+
+            public class pEpException extends RuntimeException {
+              public pEpException(String message) {
+                super(message);
+              }
+            }
+            ||
+        }
         document("../../build/marker/gen_java_Message.marker", "text") > ""
     }