refactor: Extension module

hippo4j-common/src/main/java/cn/hippo4j/common/constant/HttpMediaType.java

@@ -21,8 +21,6 @@ import cn.hippo4j.common.toolkit.StringUtil;
 
 /**
  * Http media type.
- *
- * @author Rongzhen Yan
  */
 public final class HttpMediaType {
 

hippo4j-common/src/main/java/cn/hippo4j/common/constant/HttpMethod.java

@@ -19,8 +19,6 @@ package cn.hippo4j.common.constant;
 
 /**
  * Http method constants.
- *
- * @author Rongzhen Yan
  */
 public class HttpMethod {
 

hippo4j-common/src/main/java/cn/hippo4j/common/constant/HttpResponseCode.java

@@ -19,8 +19,6 @@ package cn.hippo4j.common.constant;
 
 /**
  * Http response code.
- *
- * @author Rongzhen Yan
  */
 public class HttpResponseCode {
 

hippo4j-common/src/main/java/cn/hippo4j/common/extension/IExtension.java

@@ -0,0 +1,24 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension;
+
+/**
+ * Top level interface of extension-point.
+ */
+public interface IExtension {
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/IExtensionRequest.java

@@ -0,0 +1,24 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension;
+
+/**
+ * Top level interface of extension-point request obj.
+ */
+public interface IExtensionRequest {
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/annotation/Realization.java

@@ -0,0 +1,35 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.annotation;
+
+import org.springframework.stereotype.Component;
+
+import java.lang.annotation.*;
+
+@Inherited
+@Retention(RetentionPolicy.RUNTIME)
+@Target({ElementType.TYPE})
+@Component
+public @interface Realization {
+
+    String code() default "DEFAULT_CODE";
+
+    String name() default "DEFAULT_NAME";
+
+    int order() default 0;
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/config/ExtensionRegisterBootstrap.java

@@ -0,0 +1,64 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.config;
+
+import cn.hippo4j.common.extension.IExtension;
+import cn.hippo4j.common.extension.annotation.Realization;
+import cn.hippo4j.common.extension.support.ExtensionRegistry;
+import cn.hippo4j.common.toolkit.ClassUtil;
+import org.springframework.beans.BeansException;
+import org.springframework.boot.ApplicationArguments;
+import org.springframework.boot.ApplicationRunner;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationContextAware;
+
+import java.util.Map;
+
+/**
+ * Extension register bootstrap
+ */
+public class ExtensionRegisterBootstrap implements ApplicationContextAware, ApplicationRunner {
+
+    private ExtensionRegistry registry = ExtensionRegistry.getInstance();
+
+    private ApplicationContext applicationContext;
+
+    @Override
+    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
+        this.applicationContext = applicationContext;
+    }
+
+    @Override
+    public void run(ApplicationArguments args) throws Exception {
+
+        Map<String, Object> realizationBeanMap = applicationContext.getBeansWithAnnotation(Realization.class);
+        realizationBeanMap.values().forEach(
+                realization -> {
+                    if (isInfrastructureClass(realization)) {
+                        return;
+                    }
+                    if (realization instanceof IExtension) {
+                        registry.register((IExtension) realization);
+                    }
+                });
+    }
+
+    private boolean isInfrastructureClass(Object obj) {
+        return obj.getClass().isAssignableFrom(IExtension.class);
+    }
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/reducer/AllMatch.java

@@ -0,0 +1,62 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.reducer;
+
+import cn.hippo4j.common.extension.IExtension;
+import cn.hippo4j.common.extension.support.ReduceType;
+import cn.hippo4j.common.toolkit.CollectionUtil;
+import lombok.Getter;
+import lombok.NonNull;
+
+import java.util.Objects;
+import java.util.function.Predicate;
+
+/**
+ * All-match extension reduce policy.
+ */
+public class AllMatch<Element> extends Reducer<Element, Boolean> {
+
+    @Getter
+    private final Predicate<Element> predicate;
+
+    public AllMatch(@NonNull Predicate<Element> predicate) {
+        Objects.requireNonNull(predicate);
+        this.predicate = predicate;
+        setResult(true);
+    }
+
+    @Override
+    public Boolean reduce() {
+        if (CollectionUtil.isEmpty(extensionImplementations)) {
+            return false;
+        } else {
+            for (IExtension extensionImpl : extensionImplementations) {
+                if (!predicate.test(getCallback().apply(extensionImpl))) {
+                    return false;
+                }
+            }
+        }
+        return true;
+    }
+
+    @Override
+    public ReduceType reducerType() {
+        return ReduceType.ALL;
+    }
+
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/reducer/AnyMatch.java

@@ -0,0 +1,61 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.reducer;
+
+import cn.hippo4j.common.extension.IExtension;
+import cn.hippo4j.common.extension.support.ReduceType;
+import cn.hippo4j.common.toolkit.CollectionUtil;
+import lombok.Getter;
+import lombok.NonNull;
+
+import java.util.Objects;
+import java.util.function.Predicate;
+
+/**
+ * Any-match extension reduce policy.
+ */
+public class AnyMatch<Element> extends Reducer<Element, Boolean> {
+
+    @Getter
+    private final Predicate<Element> predicate;
+
+    public AnyMatch(@NonNull Predicate<Element> predicate) {
+        Objects.requireNonNull(predicate);
+        this.predicate = predicate;
+        this.setResult(false);
+    }
+
+    @Override
+    public Boolean reduce() {
+        if (CollectionUtil.isEmpty(extensionImplementations)) {
+            return false;
+        }
+        for (IExtension extension : extensionImplementations) {
+            if (predicate.test(getCallback().apply(extension))) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    @Override
+    public ReduceType reducerType() {
+        return ReduceType.FIRST;
+    }
+
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/reducer/FirstOf.java

@@ -0,0 +1,54 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.reducer;
+
+import cn.hippo4j.common.extension.IExtension;
+import cn.hippo4j.common.extension.support.ReduceType;
+import lombok.NonNull;
+
+import java.util.Objects;
+import java.util.function.Predicate;
+
+/**
+ * First-of extension reduce policy.
+ */
+public class FirstOf<Element> extends Reducer<Element, Element> {
+
+    private Predicate<Element> predicate;
+
+    public FirstOf(@NonNull Predicate<Element> predicate) {
+        Objects.requireNonNull(predicate);
+        this.predicate = predicate;
+    }
+
+    @Override
+    public ReduceType reducerType() {
+        return ReduceType.FIRST;
+    }
+
+    @Override
+    public Element reduce() {
+        for (IExtension extension : extensionImplementations) {
+            Element element = getCallback().apply(extension);
+            if (null == predicate || predicate.test(element)) {
+                return element;
+            }
+        }
+        return null;
+    }
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/reducer/None.java

@@ -0,0 +1,36 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.reducer;
+
+import cn.hippo4j.common.extension.support.ReduceType;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class None<Element> extends Reducer<Element, List<Element>> {
+
+    @Override
+    public ReduceType reducerType() {
+        return ReduceType.NONE;
+    }
+
+    @Override
+    public List<Element> reduce() {
+        return extensionImplementations.stream().map(getCallback()).collect(Collectors.toList());
+    }
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/reducer/Reducer.java

@@ -0,0 +1,64 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.reducer;
+
+import cn.hippo4j.common.extension.IExtension;
+import cn.hippo4j.common.extension.IExtensionRequest;
+import cn.hippo4j.common.extension.support.ExtensionCallback;
+import cn.hippo4j.common.extension.support.ReduceType;
+import lombok.Getter;
+import lombok.Setter;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public abstract class Reducer<Element, Result> {
+
+    @Getter
+    private boolean hasBreak = false;
+
+    @Getter
+    private Result result;
+
+    @Setter
+    protected IExtensionRequest request;
+
+    @Setter
+    protected List<IExtension> extensionImplementations;
+
+    @Setter
+    @Getter
+    private ExtensionCallback<IExtension, Element> callback;
+
+    public abstract Result reduce();
+
+    public boolean willBreak() {
+        return false;
+    }
+
+    public void setResult(Result result) {
+        this.result = result;
+    }
+
+    public abstract ReduceType reducerType();
+
+    public String reduceName() {
+        return this.getClass().getSimpleName();
+    }
+
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/reducer/Reducers.java

@@ -0,0 +1,77 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.reducer;
+
+import lombok.NonNull;
+
+import java.util.List;
+import java.util.Objects;
+import java.util.function.Predicate;
+
+@SuppressWarnings("all")
+public class Reducers {
+
+    /**
+     * No reduce policy needed.
+     *
+     * @return None type reducer
+     */
+    public static <E> Reducer<E, List<E>> none() {
+        return new None<>();
+    }
+
+    /**
+     * Build a FirstOf Reducer.
+     *
+     * @param predicate the condition predicate.
+     * @return FirstOf Policy Reducer.
+     */
+    public static <E> Reducer<E, E> firstOf(@NonNull Predicate<E> predicate) {
+        return new FirstOf<>(predicate);
+    }
+
+    /**
+     * Build a FirstOf Not-null Reducer.
+     *
+     * @return FirstOf Not-null Policy Reducer.
+     */
+    public static <E> Reducer<E, E> firstOfNotNull() {
+        return new FirstOf<>(Objects::nonNull);
+    }
+
+    /**
+     * Build a AnyMatch Reducer.
+     *
+     * @param predicate the condition predicate.
+     * @return AnyMatch Policy Reducer.
+     */
+    public static <E> Reducer<E, Boolean> anyMatch(Predicate<E> predicate) {
+        return new AnyMatch<>(predicate);
+    }
+
+    /**
+     * Build a AllMatch Reducer
+     *
+     * @param predicate the condition predicate.
+     * @return AllMatch Policy Reducer.
+     */
+    public static <E> Reducer<E, Boolean> allMatch(@NonNull Predicate<E> predicate) {
+        return new AllMatch<>(predicate);
+    }
+
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/support/ExtensionAutoConfiguration.java

@@ -0,0 +1,31 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.support;
+
+import cn.hippo4j.common.extension.config.ExtensionRegisterBootstrap;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+public class ExtensionAutoConfiguration {
+
+    @Bean
+    public ExtensionRegisterBootstrap bootstrap() {
+        return new ExtensionRegisterBootstrap();
+    }
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/support/ExtensionCallback.java

@@ -0,0 +1,31 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.support;
+
+import java.util.function.Function;
+
+/**
+ * Callback function of extension invocation.
+ * @param <T>
+ * @param <R>
+ */
+@FunctionalInterface
+public interface ExtensionCallback<T, R> extends Function<T, R> {
+
+    R apply(T extension);
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/support/ExtensionInvoker.java

@@ -0,0 +1,61 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.support;
+
+import cn.hippo4j.common.extension.IExtension;
+import cn.hippo4j.common.extension.reducer.Reducer;
+import cn.hippo4j.common.extension.reducer.Reducers;
+import cn.hippo4j.common.spi.DynamicThreadPoolServiceLoader;
+import cn.hippo4j.common.toolkit.Assert;
+import cn.hippo4j.common.toolkit.CollectionUtil;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Extension point invoker.
+ *
+ * Providing extension-point invocation ability that supports the use of reducing policy.
+ */
+public class ExtensionInvoker {
+
+    private static final ExtensionRegistry registry = ExtensionRegistry.getInstance();
+
+    public static <T extends IExtension, E> List<E> reduceExecute(Class<T> targetClz,
+                                                                  ExtensionCallback<T, E> callback) {
+        return reduceExecute(targetClz, callback, Reducers.none());
+    }
+
+    @SuppressWarnings("unchecked")
+    public static <T extends IExtension, E, R> R reduceExecute(Class<T> targetClz,
+                                                               ExtensionCallback<T, E> callback,
+                                                               Reducer<E, R> reducer) {
+        Assert.isTrue(IExtension.class.isAssignableFrom(targetClz),
+                "can not execute extension point. please implement base extension interface(" + IExtension.class.getName() + ") first.");
+
+        List<IExtension> implementations = registry.find(targetClz);
+        if (CollectionUtil.isEmpty(implementations)) {
+            implementations = new ArrayList<>(DynamicThreadPoolServiceLoader.getSingletonServiceInstances(targetClz));
+        }
+        Assert.notEmpty(implementations, "can not find any extension realizations with interface: " + targetClz.getName());
+
+        reducer.setExtensionImplementations(implementations);
+        reducer.setCallback((ExtensionCallback<IExtension, E>) callback);
+        return reducer.reduce();
+    }
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/support/ExtensionRegistry.java

@@ -0,0 +1,97 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.support;
+
+import cn.hippo4j.common.extension.IExtension;
+import cn.hippo4j.common.extension.annotation.Realization;
+import cn.hippo4j.common.toolkit.CollectionUtil;
+import cn.hippo4j.common.toolkit.logtracing.LogMessage;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.aop.support.AopUtils;
+import org.springframework.util.ClassUtils;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Extension registry
+ */
+@Slf4j
+public class ExtensionRegistry implements IExtensionRegistry {
+
+    private final Map<Class<? extends IExtension>, List<IExtension>> registry = new ConcurrentHashMap<>();
+
+    private static ExtensionRegistry INSTANCE;
+
+    private ExtensionRegistry() {
+    }
+
+    public static ExtensionRegistry getInstance() {
+        if (null == INSTANCE) {
+            synchronized (ExtensionRegistry.class) {
+                if (null == INSTANCE) {
+                    INSTANCE = new ExtensionRegistry();
+                }
+            }
+        }
+        return INSTANCE;
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public void register(IExtension implementation) {
+
+        Class<?> implClass = implementation.getClass();
+        if (AopUtils.isAopProxy(implClass)) {
+            implClass = ClassUtils.getUserClass(implClass);
+        }
+        Realization annotation = implClass.getAnnotation(Realization.class);
+
+        Class<?>[] interfaces = implClass.getInterfaces();
+
+        for (Class<?> intf : interfaces) {
+            if (IExtension.class.isAssignableFrom(intf)) {
+                this.register((Class<IExtension>) intf, implementation);
+            }
+        }
+    }
+
+    private void register(Class<? extends IExtension> extension, IExtension realization) {
+        if (!registry.containsKey(extension) || CollectionUtil.isEmpty(registry.get(extension))) {
+            List<IExtension> implementations = new ArrayList<>();
+            implementations.add(realization);
+            registry.put(extension, implementations);
+        } else {
+            if (registry.get(extension).contains(realization)) {
+                log.warn(LogMessage.getInstance()
+                        .kv("realizationClassName", realization.getClass().getName())
+                        .msg("Extension realization already registered, skip."));
+            }
+            List<IExtension> implementations = registry.get(extension);
+            implementations.add(realization);
+            registry.put(extension, implementations);
+        }
+    }
+
+    @Override
+    public List<IExtension> find(Class<? extends IExtension> extension) {
+        return registry.get(extension);
+    }
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/support/IExtensionRegistry.java

@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.support;
+
+import cn.hippo4j.common.extension.IExtension;
+
+import java.util.List;
+
+public interface IExtensionRegistry {
+
+    void register(IExtension realization);
+
+    List<IExtension> find(Class<? extends IExtension> extension);
+}

hippo4j-common/src/main/java/cn/hippo4j/common/extension/support/ReduceType.java

@@ -0,0 +1,26 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.support;
+
+public enum ReduceType {
+
+    NONE,
+    ALL,
+    FIRST,
+    UNKNOWN
+}

hippo4j-common/src/main/java/cn/hippo4j/common/toolkit/Assert.java

@@ -38,6 +38,12 @@ public class Assert {
         isTrue(expression, "[Assertion failed] - this expression must be true");
     }
 
+    public static void isEmpty(Collection<?> collection, String message) {
+        if (!CollectionUtil.isEmpty(collection)) {
+            throw new IllegalArgumentException(message);
+        }
+    }
+
     public static void isNull(Object object, String message) {
         if (object != null) {
             throw new IllegalArgumentException(message);

hippo4j-common/src/main/java/cn/hippo4j/common/toolkit/ClassUtil.java

@@ -0,0 +1,53 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.toolkit;
+
+/**
+ * Class Util.
+ */
+public class ClassUtil {
+
+    /**
+     * get class loader
+     *
+     * @param clazz
+     * @return class loader
+     */
+    public static ClassLoader getClassLoader(Class<?> clazz) {
+        ClassLoader cl = null;
+        try {
+            cl = Thread.currentThread().getContextClassLoader();
+        } catch (Throwable ex) {
+            // Cannot access thread context ClassLoader - falling back to system class loader...
+        }
+        if (cl == null) {
+            // No thread context class loader -> use class loader of this class.
+            cl = clazz.getClassLoader();
+            if (cl == null) {
+                // getClassLoader() returning null indicates the bootstrap ClassLoader
+                try {
+                    cl = ClassLoader.getSystemClassLoader();
+                } catch (Throwable ex) {
+                    // Cannot access system ClassLoader - oh well, maybe the caller can live with null...
+                }
+            }
+        }
+
+        return cl;
+    }
+}

hippo4j-common/src/main/java/cn/hippo4j/common/toolkit/http/HttpUtil.java

@@ -43,8 +43,6 @@ import static cn.hippo4j.common.constant.HttpHeaderConstants.CONTENT_LENGTH;
 
 /**
  * Http request utilities.
- *
- * @author Rongzhen Yan
  */
 @Slf4j
 @NoArgsConstructor(access = AccessLevel.PRIVATE)

hippo4j-common/src/main/java/cn/hippo4j/common/toolkit/http/JdkHttpClientResponse.java

@@ -30,8 +30,6 @@ import java.util.Map;
 
 /**
  * Represents a client-side HTTP response with JDK implementation
- *
- * @author Rongzhen Yan
  */
 public class JdkHttpClientResponse implements HttpClientResponse {
 

hippo4j-common/src/main/java/cn/hippo4j/common/toolkit/logtracing/LogMessage.java

@@ -28,8 +28,6 @@ import java.util.concurrent.ConcurrentHashMap;
 
 /**
  * Log message.
- *
- * @author Rongzhen Yan
  */
 @NoArgsConstructor(access = AccessLevel.PRIVATE)
 public class LogMessage {

hippo4j-common/src/main/resources/META-INF/spring.factories

@@ -0,0 +1 @@
+org.springframework.boot.autoconfigure.EnableAutoConfiguration=cn.hippo4j.common.extension.support.ExtensionAutoConfiguration

hippo4j-common/src/test/java/cn/hippo4j/common/extension/ExtensionInvokerTest.java

@@ -0,0 +1,84 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension;
+
+import cn.hippo4j.common.extension.anymatch.AnyMatchExtImplA;
+import cn.hippo4j.common.extension.anymatch.AnyMatchExtImplB;
+import cn.hippo4j.common.extension.anymatch.IAnyMatchExtension;
+import cn.hippo4j.common.extension.firstof.FirstOfExtImplA;
+import cn.hippo4j.common.extension.firstof.FirstOfExtImplB;
+import cn.hippo4j.common.extension.firstof.IFirstOfExtension;
+import cn.hippo4j.common.extension.reducer.Reducers;
+import cn.hippo4j.common.extension.spi.IOldSpi;
+import cn.hippo4j.common.extension.support.ExtensionInvoker;
+import cn.hippo4j.common.extension.support.ExtensionRegistry;
+import cn.hippo4j.common.spi.DynamicThreadPoolServiceLoader;
+import org.assertj.core.util.Lists;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import java.util.List;
+import java.util.Objects;
+
+import static org.junit.Assert.*;
+
+public class ExtensionInvokerTest {
+
+    @Before
+    public void before() {
+        ExtensionRegistry.getInstance().register(new FirstOfExtImplA());
+        ExtensionRegistry.getInstance().register(new FirstOfExtImplB());
+        ExtensionRegistry.getInstance().register(new AnyMatchExtImplA());
+        ExtensionRegistry.getInstance().register(new AnyMatchExtImplB());
+
+        DynamicThreadPoolServiceLoader.register(IOldSpi.class);
+    }
+    @Test
+    public void test() {
+
+        Integer arg = 20;
+        // first-of
+        Integer res1 = ExtensionInvoker.reduceExecute(IFirstOfExtension.class, (ext) -> ext.foo(arg),
+                Reducers.firstOfNotNull());
+        assertEquals(arg, res1);
+
+        // any-match
+        Boolean res2 = ExtensionInvoker.reduceExecute(IAnyMatchExtension.class, (ext) -> ext.foo(arg),
+                Reducers.anyMatch(Objects::nonNull));
+        assertTrue(res2);
+
+        // none
+        List<Integer> res3 = ExtensionInvoker.reduceExecute(IFirstOfExtension.class, (ext) -> ext.foo(arg));
+        assertArrayEquals(res3.toArray(new Integer[0]), Lists.newArrayList(null, arg).toArray());
+
+        // all-match
+        Boolean res4 = ExtensionInvoker.reduceExecute(IAnyMatchExtension.class, (ext) -> ext.foo(arg),
+                Reducers.allMatch(Objects::nonNull));
+        assertTrue(res4);
+
+    }
+
+    @Test
+    public void test_spi_old() {
+        Boolean res1 = ExtensionInvoker.reduceExecute(IOldSpi.class, IOldSpi::foo, Reducers.firstOfNotNull());
+        assertTrue(res1);
+    }
+}

hippo4j-common/src/test/java/cn/hippo4j/common/extension/anymatch/AnyMatchExtImplA.java

@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.anymatch;
+
+import cn.hippo4j.common.extension.annotation.Realization;
+
+@Realization
+public class AnyMatchExtImplA implements IAnyMatchExtension {
+
+    @Override
+    public Integer foo(Integer arg) {
+        return arg > 0 ? arg : null;
+    }
+}

hippo4j-common/src/test/java/cn/hippo4j/common/extension/anymatch/AnyMatchExtImplB.java

@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.anymatch;
+
+import cn.hippo4j.common.extension.annotation.Realization;
+
+@Realization
+public class AnyMatchExtImplB implements IAnyMatchExtension {
+
+    @Override
+    public Integer foo(Integer arg) {
+        return arg > 0 ? arg : null;
+    }
+}

hippo4j-common/src/test/java/cn/hippo4j/common/extension/anymatch/IAnyMatchExtension.java

@@ -0,0 +1,25 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.anymatch;
+
+import cn.hippo4j.common.extension.IExtension;
+
+public interface IAnyMatchExtension extends IExtension {
+
+    Integer foo(Integer arg);
+}

hippo4j-common/src/test/java/cn/hippo4j/common/extension/firstof/FirstOfExtImplA.java

@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.firstof;
+
+import cn.hippo4j.common.extension.annotation.Realization;
+
+@Realization
+public class FirstOfExtImplA implements IFirstOfExtension {
+
+    @Override
+    public Integer foo(Integer arg) {
+        return null;
+    }
+}

hippo4j-common/src/test/java/cn/hippo4j/common/extension/firstof/FirstOfExtImplB.java

@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.firstof;
+
+import cn.hippo4j.common.extension.annotation.Realization;
+
+@Realization
+public class FirstOfExtImplB implements IFirstOfExtension {
+
+    @Override
+    public Integer foo(Integer arg) {
+        return arg;
+    }
+}

hippo4j-common/src/test/java/cn/hippo4j/common/extension/firstof/IFirstOfExtension.java

@@ -0,0 +1,25 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.firstof;
+
+import cn.hippo4j.common.extension.IExtension;
+
+public interface IFirstOfExtension extends IExtension {
+
+    Integer foo(Integer arg);
+}

hippo4j-common/src/test/java/cn/hippo4j/common/extension/spi/IOldSpi.java

@@ -0,0 +1,25 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.spi;
+
+import cn.hippo4j.common.extension.IExtension;
+
+public interface IOldSpi extends IExtension {
+
+    Boolean foo();
+}

hippo4j-common/src/test/java/cn/hippo4j/common/extension/spi/IOldSpiImplA.java

@@ -0,0 +1,27 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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
+ *
+ *     http://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 cn.hippo4j.common.extension.spi;
+
+public class IOldSpiImplA implements IOldSpi {
+
+    @Override
+    public Boolean foo() {
+        System.out.println(this.getClass().getName());
+        return true;
+    }
+}

hippo4j-common/src/test/resources/META-INF/services/cn.hippo4j.common.extension.spi.IOldSpi

@@ -0,0 +1 @@
+cn.hippo4j.common.extension.spi.IOldSpiImplA