error handling refactoring: made BaseClientActor an Akka state machine

* manage the current connectivity state in BaseClientActor
* AMQP1.0 and RMQ clients use the API of their superclass

Signed-off-by: Thomas Jaeckle <thomas.jaeckle@bosch-si.com>

model/connectivity/src/main/java/org/eclipse/ditto/model/connectivity/ConnectionMetrics.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2017 Bosch Software Innovations GmbH.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/org/documents/epl-2.0/index.php
+ *
+ * Contributors:
+ *    Bosch Software Innovations GmbH - initial contribution
+ */
+package org.eclipse.ditto.model.connectivity;
+
+import java.util.Optional;
+
+import javax.annotation.concurrent.Immutable;
+
+import org.eclipse.ditto.json.JsonFactory;
+import org.eclipse.ditto.json.JsonField;
+import org.eclipse.ditto.json.JsonFieldDefinition;
+import org.eclipse.ditto.json.JsonFieldSelector;
+import org.eclipse.ditto.json.JsonObject;
+import org.eclipse.ditto.model.base.json.FieldType;
+import org.eclipse.ditto.model.base.json.JsonSchemaVersion;
+import org.eclipse.ditto.model.base.json.Jsonifiable;
+
+/**
+ * TODO TJ doc
+ */
+@Immutable
+public interface ConnectionMetrics extends Jsonifiable.WithFieldSelectorAndPredicate<JsonField> {
+
+    /**
+     *
+     * @return
+     */
+    ConnectionStatus getConnectionStatus();
+
+    /**
+     *
+     * @return
+     */
+    Optional<String> getConnectionStatusDetails();
+
+
+    /**
+     * Returns all non hidden marked fields of this {@code Connection}.
+     *
+     * @return a JSON object representation of this Connection including only non hidden marked fields.
+     */
+    @Override
+    default JsonObject toJson() {
+        return toJson(FieldType.notHidden());
+    }
+
+    @Override
+    default JsonObject toJson(final JsonSchemaVersion schemaVersion, final JsonFieldSelector fieldSelector) {
+        return toJson(schemaVersion, FieldType.notHidden()).get(fieldSelector);
+    }
+
+    /**
+     * An enumeration of the known {@code JsonField}s of a {@code ConnectionMetrics}.
+     */
+    @Immutable
+    final class JsonFields {
+
+        /**
+         * JSON field containing the {@code ConnectionStatus} identifier.
+         */
+        public static final JsonFieldDefinition<String> CONNECTION_STATUS =
+                JsonFactory.newStringFieldDefinition("connectionStatus", FieldType.REGULAR, JsonSchemaVersion.V_1,
+                        JsonSchemaVersion.V_2);
+
+        /**
+         * JSON field containing the {@code ConnectionStatus} identifier.
+         */
+        public static final JsonFieldDefinition<String> CONNECTION_STATUS_DETAILS =
+                JsonFactory.newStringFieldDefinition("connectionStatusDetails", FieldType.REGULAR, JsonSchemaVersion.V_1,
+                        JsonSchemaVersion.V_2);
+
+        private JsonFields() {
+            throw new AssertionError();
+        }
+
+    }
+}

model/connectivity/src/main/java/org/eclipse/ditto/model/connectivity/ConnectivityModelFactory.java

@@ -14,6 +14,7 @@
 import java.util.Map;
 import java.util.Set;
 
+import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
 
 import org.eclipse.ditto.json.JsonObject;
@@ -57,6 +58,32 @@ public static Connection connectionFromJson(final JsonObject jsonObject) {
         return ImmutableConnection.fromJson(jsonObject);
     }
 
+    /**
+     * Creates a new {@code ConnectionMetrics} object from the specified JSON object.
+     *
+     * @param jsonObject a JSON object which provides the data for the Connection to be created.
+     * @return a new ConnectionMetrics which is initialised with the extracted data from {@code jsonObject}.
+     * @throws NullPointerException if {@code jsonObject} is {@code null}.
+     * @throws org.eclipse.ditto.json.JsonParseException if {@code jsonObject} is not an appropriate JSON object.
+     */
+    public static ConnectionMetrics connectionMetricsFromJson(final JsonObject jsonObject) {
+        return ImmutableConnectionMetrics.fromJson(jsonObject);
+    }
+
+    /**
+     * Retruens a new {@code ConnectionMetrics}.
+     *
+     * @param connectionStatus the ConnectionStatus of the metrics to create
+     * @param connectionStatusDetails the optional details about the connection status
+     * @return a new ConnectionMetrics which is initialised with the extracted data from {@code jsonObject}.
+     * @throws NullPointerException if {@code connectionStatus} is {@code null}.
+     */
+    public static ConnectionMetrics newConnectionMetrics(final ConnectionStatus connectionStatus,
+            final @Nullable String connectionStatusDetails) {
+        return ImmutableConnectionMetrics.of(connectionStatus, connectionStatusDetails);
+    }
+
+
     /**
      * Returns a new {@code MappingContext}.
      *

model/connectivity/src/main/java/org/eclipse/ditto/model/connectivity/ImmutableConnectionMetrics.java

@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 2017 Bosch Software Innovations GmbH.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/org/documents/epl-2.0/index.php
+ *
+ * Contributors:
+ *    Bosch Software Innovations GmbH - initial contribution
+ */
+package org.eclipse.ditto.model.connectivity;
+
+import static org.eclipse.ditto.model.base.common.ConditionChecker.checkNotNull;
+
+import java.util.Objects;
+import java.util.Optional;
+import java.util.function.Predicate;
+
+import javax.annotation.Nullable;
+import javax.annotation.concurrent.Immutable;
+
+import org.eclipse.ditto.json.JsonFactory;
+import org.eclipse.ditto.json.JsonField;
+import org.eclipse.ditto.json.JsonObject;
+import org.eclipse.ditto.json.JsonObjectBuilder;
+import org.eclipse.ditto.model.base.json.JsonSchemaVersion;
+
+/**
+ * TODO TJ doc
+ */
+@Immutable
+final class ImmutableConnectionMetrics implements ConnectionMetrics {
+
+    private final ConnectionStatus connectionStatus;
+    @Nullable private final String connectionStatusDetails;
+
+    private ImmutableConnectionMetrics(final ConnectionStatus connectionStatus,
+            @Nullable final String connectionStatusDetails) {
+
+        this.connectionStatus = connectionStatus;
+        this.connectionStatusDetails = connectionStatusDetails;
+    }
+
+    /**
+     * Creates a new {@code ImmutableConnectionMetrics} instance.
+     *
+     * @param connectionStatus the ConnectionStatus of the metrics to create
+     * @param connectionStatusDetails the optional details about the connection status
+     * @return a new instance of ConnectionMetrics.
+     */
+    public static ImmutableConnectionMetrics of(final ConnectionStatus connectionStatus,
+            @Nullable final String connectionStatusDetails) {
+        checkNotNull(connectionStatus, "connectionStatus");
+        checkNotNull(connectionStatusDetails, "connectionStatusDetails");
+
+        return new ImmutableConnectionMetrics(connectionStatus, connectionStatusDetails);
+    }
+
+    /**
+     * Creates a new {@code ConnectionMetrics} object from the specified JSON object.
+     *
+     * @param jsonObject a JSON object which provides the data for the ConnectionMetrics to be created.
+     * @return a new ConnectionMetrics which is initialised with the extracted data from {@code jsonObject}.
+     * @throws NullPointerException if {@code jsonObject} is {@code null}.
+     * @throws org.eclipse.ditto.json.JsonParseException if {@code jsonObject} is not an appropriate JSON object.
+     */
+    public static ConnectionMetrics fromJson(final JsonObject jsonObject) {
+        final ConnectionStatus readConnectionStatus = ConnectionStatus.forName(
+                jsonObject.getValueOrThrow(JsonFields.CONNECTION_STATUS)).orElse(ConnectionStatus.UNKNOWN);
+        final String readConnectionStatusDetails = jsonObject.getValueOrThrow(JsonFields.CONNECTION_STATUS_DETAILS);
+
+        return of(readConnectionStatus, readConnectionStatusDetails);
+    }
+
+    @Override
+    public ConnectionStatus getConnectionStatus() {
+        return connectionStatus;
+    }
+
+    @Override
+    public Optional<String> getConnectionStatusDetails() {
+        return Optional.ofNullable(connectionStatusDetails);
+    }
+
+    @Override
+    public JsonObject toJson(final JsonSchemaVersion schemaVersion, final Predicate<JsonField> thePredicate) {
+        final Predicate<JsonField> predicate = schemaVersion.and(thePredicate);
+        final JsonObjectBuilder jsonObjectBuilder = JsonFactory.newObjectBuilder();
+        jsonObjectBuilder.set(JsonFields.CONNECTION_STATUS, connectionStatus.getName(), predicate);
+        if (connectionStatusDetails != null) {
+            jsonObjectBuilder.set(JsonFields.CONNECTION_STATUS_DETAILS, connectionStatusDetails, predicate);
+        }
+        return jsonObjectBuilder.build();
+    }
+
+    @Override
+    public boolean equals(final Object o) {
+        if (this == o) {return true;}
+        if (!(o instanceof ImmutableConnectionMetrics)) {return false;}
+        final ImmutableConnectionMetrics that = (ImmutableConnectionMetrics) o;
+        return connectionStatus == that.connectionStatus &&
+                Objects.equals(connectionStatusDetails, that.connectionStatusDetails);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(connectionStatus, connectionStatusDetails);
+    }
+
+    @Override
+    public String toString() {
+        return getClass().getSimpleName() + " [" +
+                "connectionStatus=" + connectionStatus +
+                ", connectionStatusDetails=" + connectionStatusDetails +
+                "]";
+    }
+
+}