From 927cbc705a66aff0f35c57a2fb48187c4a7ce4ed Mon Sep 17 00:00:00 2001
From: "le.kuang" <1741461577@qq.com>
Date: Mon, 6 Feb 2023 11:16:37 +0800
Subject: [PATCH] Optimize ConcurrentHashMap#computeIfAbsent have performance
 problem in jdk1.8

---
 .../austin/support/utils/AccountUtils.java    | 11 ++---
 .../support/utils/ConcurrentHashMapUtils.java | 41 +++++++++++++++++++
 2 files changed, 47 insertions(+), 5 deletions(-)
 create mode 100644 austin-support/src/main/java/com/java3y/austin/support/utils/ConcurrentHashMapUtils.java

diff --git a/austin-support/src/main/java/com/java3y/austin/support/utils/AccountUtils.java b/austin-support/src/main/java/com/java3y/austin/support/utils/AccountUtils.java
index cf616f6..10699f4 100644
--- a/austin-support/src/main/java/com/java3y/austin/support/utils/AccountUtils.java
+++ b/austin-support/src/main/java/com/java3y/austin/support/utils/AccountUtils.java
@@ -24,9 +24,9 @@ import org.springframework.context.annotation.Configuration;
 import org.springframework.data.redis.core.StringRedisTemplate;
 
 import java.util.List;
-import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
 
 /**
  * 获取账号信息工具类
@@ -45,8 +45,8 @@ public class AccountUtils {
     /**
      * 消息的小程序/微信服务号账号
      */
-    private Map<ChannelAccount, WxMpService> officialAccountServiceMap = new ConcurrentHashMap<>();
-    private Map<ChannelAccount, WxMaService> miniProgramServiceMap = new ConcurrentHashMap<>();
+    private ConcurrentMap<ChannelAccount, WxMpService> officialAccountServiceMap = new ConcurrentHashMap<>();
+    private ConcurrentMap<ChannelAccount, WxMaService> miniProgramServiceMap = new ConcurrentHashMap<>();
 
     @Bean
     public RedisTemplateWxRedisOps redisTemplateWxRedisOps() {
@@ -63,15 +63,16 @@ public class AccountUtils {
      * @param <T>
      * @return
      */
+    @SuppressWarnings("unchecked")
     public <T> T getAccountById(Integer sendAccountId, Class<T> clazz) {
         try {
             Optional<ChannelAccount> optionalChannelAccount = channelAccountDao.findById(Long.valueOf(sendAccountId));
             if (optionalChannelAccount.isPresent()) {
                 ChannelAccount channelAccount = optionalChannelAccount.get();
                 if (clazz.equals(WxMaService.class)) {
-                    return (T) miniProgramServiceMap.computeIfAbsent(channelAccount, account -> initMiniProgramService(JSON.parseObject(account.getAccountConfig(), WeChatMiniProgramAccount.class)));
+                    return (T)ConcurrentHashMapUtils.computeIfAbsent(miniProgramServiceMap, channelAccount, account -> initMiniProgramService(JSON.parseObject(account.getAccountConfig(), WeChatMiniProgramAccount.class)));
                 } else if (clazz.equals(WxMpService.class)) {
-                    return (T) officialAccountServiceMap.computeIfAbsent(channelAccount, account -> initOfficialAccountService(JSON.parseObject(account.getAccountConfig(), WeChatOfficialAccount.class)));
+                    return (T)ConcurrentHashMapUtils.computeIfAbsent(officialAccountServiceMap, channelAccount, account -> initOfficialAccountService(JSON.parseObject(account.getAccountConfig(), WeChatOfficialAccount.class)));
                 } else {
                     return JSON.parseObject(channelAccount.getAccountConfig(), clazz);
                 }
diff --git a/austin-support/src/main/java/com/java3y/austin/support/utils/ConcurrentHashMapUtils.java b/austin-support/src/main/java/com/java3y/austin/support/utils/ConcurrentHashMapUtils.java
new file mode 100644
index 0000000..f4bd3ac
--- /dev/null
+++ b/austin-support/src/main/java/com/java3y/austin/support/utils/ConcurrentHashMapUtils.java
@@ -0,0 +1,41 @@
+package com.java3y.austin.support.utils;
+
+import java.util.concurrent.ConcurrentMap;
+import java.util.function.Function;
+
+/**
+ * @author kl
+ * @version 1.0.0
+ * @description ConcurrentHashMap util
+ * @date 2023/2/6 10:01
+ */
+public class ConcurrentHashMapUtils {
+
+    private static boolean IS_JAVA8;
+
+    static {
+        try {
+            IS_JAVA8 = System.getProperty("java.version").startsWith("1.8.");
+        } catch (Exception ignore) {
+            // exception is ignored
+            IS_JAVA8 = true;
+        }
+    }
+
+    /**
+     * Java 8 ConcurrentHashMap#computeIfAbsent 存在性能问题的临时解决方案
+     * @see <a href="https://bugs.openjdk.java.net/browse/JDK-8161372">https://bugs.openjdk.java.net/browse/JDK-8161372</a>
+     *
+     */
+    public static <K, V> V computeIfAbsent(ConcurrentMap<K, V> map, K key, Function<? super K, ? extends V> func) {
+        if (IS_JAVA8) {
+            V v = map.get(key);
+            if (null == v) {
+                v = map.computeIfAbsent(key, func);
+            }
+            return v;
+        } else {
+            return map.computeIfAbsent(key, func);
+        }
+    }
+}