optimize: add jdbc class isolation loader for different versions

core/src/main/java/org/apache/seata/core/store/db/AbstractDataSourceProvider.java

@@ -16,6 +16,15 @@
  */
 package org.apache.seata.core.store.db;
 
+import java.io.File;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Objects;
+import java.util.stream.Stream;
+
 import javax.sql.DataSource;
 
 import org.apache.seata.common.exception.StoreException;
@@ -47,8 +56,20 @@ public abstract class AbstractDataSourceProvider implements DataSourceProvider,
      */
     protected static final Configuration CONFIG = ConfigurationFactory.getInstance();
 
+    private final static String MYSQL_DRIVER_CLASS_NAME = "com.mysql.jdbc.Driver";
+
+    private final static String MYSQL8_DRIVER_CLASS_NAME = "com.mysql.cj.jdbc.Driver";
+
+    private final static String MYSQL_DRIVER_FILE_PREFIX = "mysql-connector-java-";
+
+    private final static Map<String, ClassLoader> MYSQL_DRIVER_LOADERS;
+
     private static final long DEFAULT_DB_MAX_WAIT = 5000;
 
+    static {
+        MYSQL_DRIVER_LOADERS = createMysqlDriverClassLoaders();
+    }
+
     @Override
     public void init() {
         this.dataSource = generate();
@@ -67,7 +88,7 @@ public DataSource generate() {
     public void validate() {
         //valid driver class name
         String driverClassName = getDriverClassName();
-        ClassLoader loader = Thread.currentThread().getContextClassLoader();
+        ClassLoader loader = getDriverClassLoader();
         if (null == loader) {
             throw new StoreException("class loader set error, you should not use the Bootstrap classloader");
         }
@@ -124,7 +145,50 @@ protected Long getMaxWait() {
     }
 
     protected ClassLoader getDriverClassLoader() {
-        return ClassLoader.getSystemClassLoader();
+        return MYSQL_DRIVER_LOADERS.getOrDefault(getDriverClassName(), ClassLoader.getSystemClassLoader());
+    }
+
+    private static Map<String, ClassLoader> createMysqlDriverClassLoaders() {
+        Map<String, ClassLoader> loaders = new HashMap<>();
+        String cp = System.getProperty("java.class.path");
+        if (cp == null || cp.isEmpty()) {
+            return loaders;
+        }
+        Stream.of(cp.split(File.pathSeparator))
+            .map(File::new)
+            .filter(File::exists)
+            .map(file -> file.isFile() ? file.getParentFile() : file)
+            .filter(Objects::nonNull)
+            .filter(File::isDirectory)
+            .map(file -> new File(file, "jdbc"))
+            .filter(File::exists)
+            .filter(File::isDirectory)
+            .distinct()
+            .flatMap(file -> {
+                File[] files = file.listFiles((f, name) -> name.startsWith(MYSQL_DRIVER_FILE_PREFIX));
+                if (files != null) {
+                    return Stream.of(files);
+                } else {
+                    return Stream.of();
+                }
+            })
+            .forEach(file -> {
+                if (loaders.containsKey(MYSQL8_DRIVER_CLASS_NAME) && loaders.containsKey(MYSQL_DRIVER_CLASS_NAME)) {
+                    return;
+                }
+                try {
+                    URL url = file.toURI().toURL();
+                    ClassLoader loader = new URLClassLoader(new URL[]{url}, ClassLoader.getSystemClassLoader());
+                    try {
+                        loader.loadClass(MYSQL8_DRIVER_CLASS_NAME);
+                        loaders.putIfAbsent(MYSQL8_DRIVER_CLASS_NAME, loader);
+                    } catch (ClassNotFoundException e) {
+                        loaders.putIfAbsent(MYSQL_DRIVER_CLASS_NAME, loader);
+                    }
+                } catch (MalformedURLException ignore) {
+                }
+            });
+        return loaders;
     }
 
     /**