Declare clientSettings and tokenSettings as Object type to avoid compilation error with jdk8 or jdk11 (#15486)

Author: zrlw

dubbo-plugin/dubbo-spring-security/pom.xml

@@ -59,6 +59,12 @@
       <artifactId>spring-security-core</artifactId>
     </dependency>
 
+    <dependency>
+      <groupId>org.springframework.security</groupId>
+      <artifactId>spring-security-oauth2-core</artifactId>
+      <optional>true</optional>
+    </dependency>
+
     <dependency>
       <groupId>org.springframework.security</groupId>
       <artifactId>spring-security-oauth2-client</artifactId>
@@ -70,6 +76,7 @@
       <groupId>org.springframework.security</groupId>
       <artifactId>spring-security-oauth2-authorization-server</artifactId>
       <version>${spring.oauth2.server}</version>
+      <scope>test</scope>
       <optional>true</optional>
     </dependency>
     <!-- spring security -->

dubbo-plugin/dubbo-spring-security/src/main/java/org/apache/dubbo/spring/security/oauth2/RegisteredClientMixin.java

@@ -26,8 +26,6 @@
 import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import org.springframework.security.oauth2.core.AuthorizationGrantType;
 import org.springframework.security.oauth2.core.ClientAuthenticationMethod;
-import org.springframework.security.oauth2.server.authorization.settings.ClientSettings;
-import org.springframework.security.oauth2.server.authorization.settings.TokenSettings;
 
 @JsonTypeInfo(use = JsonTypeInfo.Id.CLASS)
 @JsonAutoDetect(
@@ -38,6 +36,11 @@
 @JsonIgnoreProperties(ignoreUnknown = true)
 abstract class RegisteredClientMixin {
 
+    /**
+     * declare clientSettings and tokenSettings as Object type to avoid COMPILATION ERROR when compile it with jdk8
+     * or jdk11, both ClientSettings and TokenSettings class file version are 61.0 which is higher than the version
+     * which jdk8 (class file version: 52.0) or jdk11 (class file version: 55.0) could support.
+     */
     @JsonCreator
     public RegisteredClientMixin(
             @JsonProperty("id") String id,
@@ -51,6 +54,6 @@ public RegisteredClientMixin(
             @JsonProperty("redirectUris") Set<String> redirectUris,
             @JsonProperty("postLogoutRedirectUris") Set<String> postLogoutRedirectUris,
             @JsonProperty("scopes") Set<String> scopes,
-            @JsonProperty("clientSettings") ClientSettings clientSettings,
-            @JsonProperty("tokenSettings") TokenSettings tokenSettings) {}
+            @JsonProperty("clientSettings") Object clientSettings,
+            @JsonProperty("tokenSettings") Object tokenSettings) {}
 }