Fixing analyzer warning: UNUSED_CATCH_CLAUSE
diff --git a/lib/src/client.dart b/lib/src/client.dart
index fc74147..20a4d70 100644
--- a/lib/src/client.dart
+++ b/lib/src/client.dart
@@ -112,7 +112,7 @@
     try {
       challenges = AuthenticationChallenge.parseHeader(
           response.headers['www-authenticate']);
-    } on FormatException catch (_) {
+    } on FormatException {
       return response;
     }
 
diff --git a/lib/src/credentials.dart b/lib/src/credentials.dart
index 49d2a64..2a7087f 100644
--- a/lib/src/credentials.dart
+++ b/lib/src/credentials.dart
@@ -95,7 +95,7 @@
     var parsed;
     try {
       parsed = JSON.decode(json);
-    } on FormatException catch (_) {
+    } on FormatException {
       validate(false, 'invalid JSON');
     }
 
diff --git a/lib/src/handle_access_token_response.dart b/lib/src/handle_access_token_response.dart
index 94d9487..c9e80fd 100644
--- a/lib/src/handle_access_token_response.dart
+++ b/lib/src/handle_access_token_response.dart
@@ -44,7 +44,7 @@
   var parameters;
   try {
     parameters = JSON.decode(response.body);
-  } on FormatException catch (_) {
+  } on FormatException {
     validate(false, 'invalid JSON');
   }
 
@@ -111,7 +111,7 @@
   var parameters;
   try {
     parameters = JSON.decode(response.body);
-  } on FormatException catch (_) {
+  } on FormatException {
     validate(false, 'invalid JSON');
   }