Clean up: remove unused codes (#3246)

apm-protocol/apm-network/src/main/java/org/apache/skywalking/apm/network/trace/component/ComponentsDefine.java

@@ -127,68 +127,4 @@ public class ComponentsDefine {
     public static final OfficialComponent SPRING_ASYNC = new OfficialComponent(65, "SpringAsync");
 
     public static final OfficialComponent JDK_HTTP = new OfficialComponent(66, "JdkHttp");
-
-    private static ComponentsDefine INSTANCE = new ComponentsDefine();
-
-    private String[] components;
-
-    public static ComponentsDefine getInstance() {
-        return INSTANCE;
-    }
-
-    public ComponentsDefine() {
-        components = new String[100];
-        addComponent(TOMCAT);
-        addComponent(HTTPCLIENT);
-        addComponent(DUBBO);
-        addComponent(MOTAN);
-        addComponent(RESIN);
-        addComponent(FEIGN);
-        addComponent(OKHTTP);
-        addComponent(SPRING_REST_TEMPLATE);
-        addComponent(SPRING_MVC_ANNOTATION);
-        addComponent(STRUTS2);
-        addComponent(NUTZ_MVC_ANNOTATION);
-        addComponent(NUTZ_HTTP);
-        addComponent(JETTY_CLIENT);
-        addComponent(JETTY_SERVER);
-        addComponent(SHARDING_JDBC);
-        addComponent(SHARDING_SPHERE);
-        addComponent(GRPC);
-        addComponent(ELASTIC_JOB);
-        addComponent(HTTP_ASYNC_CLIENT);
-        addComponent(SERVICECOMB);
-        addComponent(HYSTRIX);
-        addComponent(H2_JDBC_DRIVER);
-        addComponent(MYSQL_JDBC_DRIVER);
-        addComponent(OJDBC);
-        addComponent(JEDIS);
-        addComponent(SPYMEMCACHED);
-        addComponent(XMEMCACHED);
-        addComponent(POSTGRESQL_DRIVER);
-        addComponent(ROCKET_MQ_PRODUCER);
-        addComponent(ROCKET_MQ_CONSUMER);
-        addComponent(KAFKA_PRODUCER);
-        addComponent(KAFKA_CONSUMER);
-        addComponent(MONGO_DRIVER);
-        addComponent(SOFARPC);
-        addComponent(ACTIVEMQ_PRODUCER);
-        addComponent(ACTIVEMQ_CONSUMER);
-        addComponent(UNDERTOW);
-        addComponent(RABBITMQ_PRODUCER);
-        addComponent(RABBITMQ_CONSUMER);
-        addComponent(CANAL);
-        addComponent(GSON);
-        addComponent(REDISSON);
-        addComponent(LETTUCE);
-        addComponent(ZOOKEEPER);
-        addComponent(VERTX);
-        addComponent(SPRING_CLOUD_GATEWAY);
-        addComponent(RESTEASY);
-        addComponent(SOLRJ);
-    }
-
-    private void addComponent(OfficialComponent component) {
-        components[component.getId()] = component.getName();
-    }
 }