HPCC-10001 If classpath not set use default

Helpful on environments that have been upgraded from 3.x

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>

plugins/javaembed/javaembed.cpp

@@ -88,6 +88,10 @@ public:
             newPath.append(ENVSEPCHAR);
             conf->getProp("classpath", newPath);
         }
+        else
+        {
+            newPath.append(ENVSEPCHAR).append(INSTALL_DIR).append(PATHSEPCHAR).append("classes");
+        }
         newPath.append(ENVSEPCHAR).append(".");