1 files changed, 59 insertions, 0 deletions
diff --git a/container-core/src/main/java/com/yahoo/jdisc/http/server/jetty/ExceptionWrapper.java b/container-core/src/main/java/com/yahoo/jdisc/http/server/jetty/ExceptionWrapper.java
new file mode 100644
index 00000000000..ebc10482600
--- /dev/null
+++ b/container-core/src/main/java/com/yahoo/jdisc/http/server/jetty/ExceptionWrapper.java
@@ -0,0 +1,59 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.jdisc.http.server.jetty;
+
+/**
+ * A wrapper to make exceptions leaking into Jetty easier to track. Jetty
+ * swallows all information about where an exception was thrown, so this wrapper
+ * ensures some extra information is automatically added to the contents of
+ * getMessage().
+ *
+ * @author <a href="mailto:steinar@yahoo-inc.com">Steinar Knutsen</a>
+ */
+public class ExceptionWrapper extends RuntimeException {
+    private final String message;
+
+    /**
+     * Update if serializable contents are added.
+     */
+    private static final long serialVersionUID = 1L;
+
+    public ExceptionWrapper(Throwable t) {
+        super(t);
+        this.message = formatMessage(t);
+    }
+
+    // If calling methods from the constructor, it makes life easier if the
+    // methods are static...
+    private static String formatMessage(final Throwable t) {
+        StringBuilder b = new StringBuilder();
+        Throwable cause = t;
+        while (cause != null) {
+            StackTraceElement[] trace = cause.getStackTrace();
+            String currentMsg = cause.getMessage();
+
+            if (b.length() > 0) {
+                b.append(": ");
+            }
+            b.append(t.getClass().getSimpleName()).append('(');
+            if (currentMsg != null) {
+                b.append('"').append(currentMsg).append('"');
+            }
+            b.append(')');
+            if (trace.length > 0) {
+                b.append(" at ").append(trace[0].getClassName()).append('(');
+                if (trace[0].getFileName() != null) {
+                    b.append(trace[0].getFileName()).append(':')
+                            .append(trace[0].getLineNumber());
+                }
+                b.append(')');
+            }
+            cause = cause.getCause();
+        }
+        return b.toString();
+    }
+
+    @Override
+    public String getMessage() {
+        return message;
+    }
+}