ONOS-2124 Improved web-exception handling when an anonymous exception, i.e. one without a message, is raised.
Top stack-frame will be used as a message if exception has no message of its own.
Change-Id: I28d68e05a0d805c7320e133d8e17081513cb503c
diff --git a/web/api/src/main/java/org/onosproject/rest/exceptions/AbstractMapper.java b/web/api/src/main/java/org/onosproject/rest/exceptions/AbstractMapper.java
index 6f938f4..f49202d 100644
--- a/web/api/src/main/java/org/onosproject/rest/exceptions/AbstractMapper.java
+++ b/web/api/src/main/java/org/onosproject/rest/exceptions/AbstractMapper.java
@@ -21,6 +21,8 @@
import javax.ws.rs.core.Response;
import javax.ws.rs.ext.ExceptionMapper;
+import static com.google.common.base.Strings.isNullOrEmpty;
+
/**
* Base exception mapper implementation.
*/
@@ -49,9 +51,27 @@
protected Response.ResponseBuilder response(Response.Status status,
Throwable exception) {
ObjectMapper mapper = new ObjectMapper();
+ String message = messageFrom(exception);
ObjectNode result = mapper.createObjectNode()
.put("code", status.getStatusCode())
- .put("message", exception.getMessage());
+ .put("message", message);
return Response.status(status).entity(result.toString());
}
+
+ /**
+ * Produces a response message from the supplied exception. Either it will
+ * use the exception message, if there is one, or it will use the top
+ * stack-frame message.
+ *
+ * @param exception exception from which to produce a message
+ * @return response message
+ */
+ protected String messageFrom(Throwable exception) {
+ if (isNullOrEmpty(exception.getMessage())) {
+ StackTraceElement[] trace = exception.getStackTrace();
+ return trace.length == 0 ? "Unknown error" : trace[0].toString();
+ }
+ return exception.getMessage();
+ }
+
}