From 5a4d23457a4542d71e78adfc95dac675fe9a8d58 Mon Sep 17 00:00:00 2001
From: Karson <karsontao@hotmail.com>
Date: Fri, 5 Jan 2024 17:58:43 +0800
Subject: [PATCH] add anno for some interface (#1048)

---
 .../src/main/java/com/alipay/sofa/jraft/entity/Checksum.java     | 1 +
 .../src/main/java/com/alipay/sofa/jraft/util/Copiable.java       | 1 +
 .../main/java/com/alipay/sofa/jraft/util/JRaftSignalHandler.java | 1 +
 .../src/main/java/com/alipay/sofa/jraft/util/Recyclable.java     | 1 +
 4 files changed, 4 insertions(+)

diff --git a/jraft-core/src/main/java/com/alipay/sofa/jraft/entity/Checksum.java b/jraft-core/src/main/java/com/alipay/sofa/jraft/entity/Checksum.java
index 58444ff74..035474aa5 100644
--- a/jraft-core/src/main/java/com/alipay/sofa/jraft/entity/Checksum.java
+++ b/jraft-core/src/main/java/com/alipay/sofa/jraft/entity/Checksum.java
@@ -24,6 +24,7 @@
  * @author boyan(boyan@antfin.com)
  * @since 1.2.6
  */
+@FunctionalInterface
 public interface Checksum {
 
     /**
diff --git a/jraft-core/src/main/java/com/alipay/sofa/jraft/util/Copiable.java b/jraft-core/src/main/java/com/alipay/sofa/jraft/util/Copiable.java
index ecef0c8b7..1d2fbe3a7 100644
--- a/jraft-core/src/main/java/com/alipay/sofa/jraft/util/Copiable.java
+++ b/jraft-core/src/main/java/com/alipay/sofa/jraft/util/Copiable.java
@@ -24,6 +24,7 @@
  * 2018-Apr-03 11:15:34 AM 
  * @param <T>
  */
+@FunctionalInterface
 public interface Copiable<T> {
 
     /**
diff --git a/jraft-core/src/main/java/com/alipay/sofa/jraft/util/JRaftSignalHandler.java b/jraft-core/src/main/java/com/alipay/sofa/jraft/util/JRaftSignalHandler.java
index fa46cef08..c1a64e90c 100644
--- a/jraft-core/src/main/java/com/alipay/sofa/jraft/util/JRaftSignalHandler.java
+++ b/jraft-core/src/main/java/com/alipay/sofa/jraft/util/JRaftSignalHandler.java
@@ -20,6 +20,7 @@
  *
  * @author jiachun.fjc
  */
+@FunctionalInterface
 public interface JRaftSignalHandler {
 
     void handle(final String signalName);
diff --git a/jraft-core/src/main/java/com/alipay/sofa/jraft/util/Recyclable.java b/jraft-core/src/main/java/com/alipay/sofa/jraft/util/Recyclable.java
index 8c25a377b..9e5dea973 100644
--- a/jraft-core/src/main/java/com/alipay/sofa/jraft/util/Recyclable.java
+++ b/jraft-core/src/main/java/com/alipay/sofa/jraft/util/Recyclable.java
@@ -20,6 +20,7 @@
  *
  * @author jiachun.fjc
  */
+@FunctionalInterface
 public interface Recyclable {
 
     /**