context: don't log to logger in static initialization. (#2581)
diff --git a/context/src/main/java/io/grpc/Context.java b/context/src/main/java/io/grpc/Context.java
index 1a7ac24..cae0e1f 100644
--- a/context/src/main/java/io/grpc/Context.java
+++ b/context/src/main/java/io/grpc/Context.java
@@ -131,7 +131,14 @@
Class<?> clazz = Class.forName("io.grpc.override.ContextStorageOverride");
newStorage = (Storage) clazz.getConstructor().newInstance();
} catch (ClassNotFoundException e) {
- log.log(Level.FINE, "Storage override doesn't exist. Using default.", e);
+ if (log.isLoggable(Level.FINE)) {
+ // Avoid writing to logger because custom log handlers may try to use Context, which is
+ // problemantic (e.g., NullPointerException) because the Context class has not done loading
+ // at this point. The caveat is that in environments stderr may be disabled, thus this
+ // message would go nowhere.
+ System.err.println("io.grpc.Context: Storage override doesn't exist. Using default.");
+ e.printStackTrace();
+ }
newStorage = new ThreadLocalContextStorage();
} catch (Exception e) {
error = e;