diff --git a/example/java/org/drinkless/tdlib/example/Example.java b/example/java/org/drinkless/tdlib/example/Example.java
index eb71f4e4b..486470f6e 100644
--- a/example/java/org/drinkless/tdlib/example/Example.java
+++ b/example/java/org/drinkless/tdlib/example/Example.java
@@ -615,7 +615,7 @@ public final class Example {
     }
 
     private static void onFatalError(String errorMessage) {
-        final static class ThrowError implements Runnable {
+        final class ThrowError implements Runnable {
             private final String errorMessage;
             private final AtomicLong errorThrowTime;
 
@@ -640,19 +640,19 @@ public final class Example {
                 throw new ExternalClientError("Fatal error: " + errorMessage);
             }
 
-            private static final class ClientError extends Error {
+            final class ClientError extends Error {
                 private ClientError(String message) {
                     super(message);
                 }
             }
 
-            private static final class ExternalClientError extends Error {
+            final class ExternalClientError extends Error {
                 public ExternalClientError(String message) {
                     super(message);
                 }
             }
 
-            private static boolean isDatabaseBrokenError(String message) {
+            private boolean isDatabaseBrokenError(String message) {
                 return message.contains("Wrong key or database is corrupted") ||
                         message.contains("SQL logic error or missing database") ||
                         message.contains("database disk image is malformed") ||
@@ -661,12 +661,12 @@ public final class Example {
                         message.contains("Database was corrupted and deleted during execution and can't be recreated");
             }
 
-            private static boolean isDiskFullError(String message) {
+            private boolean isDiskFullError(String message) {
                 return message.contains("PosixError : No space left on device") ||
                         message.contains("database or disk is full");
             }
 
-            private static boolean isDiskError(String message) {
+            private boolean isDiskError(String message) {
                 return message.contains("I/O error") || message.contains("Structure needs cleaning");
             }
         }