删除 SafeConcurrentHashMap。注意使用 ConcurrentHashMap#computeIfAbsent 方法时，mappingFunction 里不要调用该 map 的 computeIfAbsent 即可。

src/main/java/xyz/zhouxy/plusone/commons/base/JRE.java

@@ -1,63 +0,0 @@
-/*
- * Copyright 2023-2024 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package xyz.zhouxy.plusone.commons.base;
-
-import xyz.zhouxy.plusone.commons.util.StringTools;
-
-/**
- * JRE version
- */
-public class JRE {
-
-    private static final int JAVA_8 = 8;
-
-    public static final int CURRENT_VERSION = getJre();
-
-    public static boolean isJava8() {
-        return CURRENT_VERSION == JAVA_8;
-    }
-
-    private static int getJre() {
-        String version = System.getProperty("java.version");
-        boolean isNotBlank = StringTools.isNotBlank(version);
-        if (isNotBlank && version.startsWith("1.8")) {
-            return JAVA_8;
-        }
-        // if JRE version is 9 or above, we can get version from
-        // java.lang.Runtime.version()
-        try {
-            return getMajorVersion(version);
-        } catch (Exception e) {
-            // assuming that JRE version is 8.
-        }
-        // default java 8
-        return JAVA_8;
-    }
-
-    private static int getMajorVersion(String version) {
-        if (version.startsWith("1.")) {
-            return Integer.parseInt(version.substring(2, 3));
-        } else {
-            int dotIndex = version.indexOf(".");
-            return (dotIndex != -1) ? Integer.parseInt(version.substring(0, dotIndex)) : Integer.parseInt(version);
-        }
-    }
-
-    private JRE() {
-        throw new IllegalStateException("Utility class");
-    }
-}