Add a new Invoker class for making requests targeted at specified ip …

…and port

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/support/Address.java

@@ -0,0 +1,41 @@
+/*
+ * 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 org.apache.dubbo.rpc.cluster.support;
+
+import java.io.Serializable;
+
+public class Address implements Serializable {
+
+    private final String ip;
+
+    private final int port;
+
+    public Address(String ip, int port) {
+        this.ip = ip;
+        this.port = port;
+    }
+
+    public String getIp() {
+        return ip;
+    }
+
+    public int getPort() {
+        return port;
+    }
+
+}

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/support/UnicastCluster.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 org.apache.dubbo.rpc.cluster.support;
+
+import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.RpcException;
+import org.apache.dubbo.rpc.cluster.Cluster;
+import org.apache.dubbo.rpc.cluster.Directory;
+
+/**
+ * UnicastCluster
+ */
+public class UnicastCluster implements Cluster {
+
+    public static final String NAME = "unicast";
+
+    @Override
+    public <T> Invoker<T> join(Directory<T> directory) throws RpcException {
+        return new UnicastClusterInvoker<>(directory);
+    }
+
+}

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/support/UnicastClusterInvoker.java

@@ -0,0 +1,51 @@
+/*
+ * 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 org.apache.dubbo.rpc.cluster.support;
+
+import org.apache.dubbo.common.URL;
+import org.apache.dubbo.rpc.Invocation;
+import org.apache.dubbo.rpc.Invoker;
+import org.apache.dubbo.rpc.Result;
+import org.apache.dubbo.rpc.RpcException;
+import org.apache.dubbo.rpc.cluster.Directory;
+import org.apache.dubbo.rpc.cluster.LoadBalance;
+
+import java.util.List;
+import java.util.Optional;
+import java.util.stream.Collectors;
+
+/**
+ * UnicastClusterInvoker
+ */
+public class UnicastClusterInvoker<T> extends AbstractClusterInvoker<T> {
+
+    public UnicastClusterInvoker(Directory<T> directory) {
+        super(directory);
+    }
+
+    @Override
+    protected Result doInvoke(Invocation invocation, List<Invoker<T>> invokers, LoadBalance loadbalance) throws RpcException {
+        Address address = Address.class.cast(invocation.getObjectAttachment("address"));
+        if (!Optional.ofNullable(address).isPresent()) {
+            throw new RpcException("Address can not be empty");
+        }
+        return invokers.stream().filter(it -> {
+            URL url = it.getUrl();
+            return address.getIp().equals(url.getIp()) && (address.getPort() == url.getPort()) && it.isAvailable();
+        }).findAny().orElseThrow(() -> new RpcException("No provider available in " + invokers.stream().map(it-> it.getUrl().getIp()+":"+it.getUrl().getPort()).collect(Collectors.joining(",")))).invoke(invocation);
+    }
+}

dubbo-cluster/src/main/resources/META-INF/dubbo/internal/org.apache.dubbo.rpc.cluster.Cluster

@@ -8,4 +8,5 @@ available=org.apache.dubbo.rpc.cluster.support.AvailableCluster
 mergeable=org.apache.dubbo.rpc.cluster.support.MergeableCluster
 broadcast=org.apache.dubbo.rpc.cluster.support.BroadcastCluster
 broadcast2=org.apache.dubbo.rpc.cluster.support.BroadcastCluster2
-zone-aware=org.apache.dubbo.rpc.cluster.support.registry.ZoneAwareCluster
+zone-aware=org.apache.dubbo.rpc.cluster.support.registry.ZoneAwareCluster
+unicast=org.apache.dubbo.rpc.cluster.support.UnicastCluster