Improved implementation of KapuaException and KapuaRuntimeException

Signed-off-by: coduz <alberto.codutti@eurotech.com>

rest-api/resources/src/main/java/org/eclipse/kapua/app/api/resources/v1/resources/exception/RestApiRuntimeException.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2018 Eurotech and/or its affiliates and others
+ * Copyright (c) 2018, 2019 Eurotech and/or its affiliates and others
  *
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
@@ -15,16 +15,6 @@
 
 public class RestApiRuntimeException extends KapuaRuntimeException {
 
-    /**
-     * Constructor
-     *
-     * @param message
-     * @param throwable
-     */
-    private RestApiRuntimeException(String message, Throwable throwable) {
-        super(message, throwable);
-    }
-
     /**
      * Builds a new {@link RestApiRuntimeException} instance based on the supplied {@link RestApiErrorCodes}.
      *
@@ -54,8 +44,6 @@ public RestApiRuntimeException(RestApiErrorCodes code, Object... arguments) {
      * @param arguments
      */
     public RestApiRuntimeException(RestApiErrorCodes code, Throwable cause, Object... arguments) {
-        super(cause);
-        this.code = code;
-        args = arguments;
+        super(code, cause, arguments);
     }
 }

service/api/pom.xml

@@ -27,6 +27,10 @@
             <artifactId>swagger-annotations</artifactId>
             <version>${swagger.version}</version>
         </dependency>
+        <dependency>
+            <groupId>javax.validation</groupId>
+            <artifactId>validation-api</artifactId>
+        </dependency>
         <dependency>
             <groupId>org.slf4j</groupId>
             <artifactId>slf4j-api</artifactId>

service/api/src/main/java/org/eclipse/kapua/ExceptionMessageUtils.java

@@ -0,0 +1,94 @@
+/*******************************************************************************
+ * Copyright (c) 2016, 2019 Eurotech and/or its affiliates and others
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Eurotech - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.kapua;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.validation.constraints.NotNull;
+import java.text.MessageFormat;
+import java.util.Locale;
+import java.util.MissingResourceException;
+import java.util.ResourceBundle;
+import java.util.StringJoiner;
+
+/**
+ * Utilities to print localized error messages for {@link KapuaException}s.
+ *
+ * @since 1.1.0
+ */
+public class ExceptionMessageUtils {
+
+    private static final Logger LOG = LoggerFactory.getLogger(ExceptionMessageUtils.class);
+
+    private static final String KAPUA_GENERIC_MESSAGE = "Error: {0}";
+
+    private ExceptionMessageUtils() {
+    }
+
+    /**
+     * Gets the {@link Locale}ised message for the given {@link KapuaErrorCode}.
+     * <p>
+     * If the {@link ResourceBundle} or the {@link KapuaErrorCode} are not found, a generic message is printed.
+     *
+     * @param resourceBundleName The {@link ResourceBundle} name from which to search the {@link KapuaErrorCode}.
+     * @param locale             The {@link Locale} of the {@link ResourceBundle}.
+     * @param code               The {@link KapuaErrorCode} to search in the {@link ResourceBundle}.
+     * @param args               The arguments to use to populate the message pattern.
+     * @return The localized message for the given {@link KapuaErrorCode}.
+     * @since 1.0.0
+     */
+    public static String getLocalizedMessage(String resourceBundleName, Locale locale, KapuaErrorCode code, Object[] args) {
+
+        String pattern = getMessagePattern(resourceBundleName, locale, code);
+        if (pattern != null) {
+            return MessageFormat.format(pattern, args);
+        } else {
+            StringJoiner joiner = new StringJoiner(", ");
+            if (args != null && args.length > 0) {
+                for (Object arg : args) {
+                    joiner.add(String.valueOf(arg));
+                }
+            }
+
+            return MessageFormat.format(KAPUA_GENERIC_MESSAGE, joiner.toString());
+        }
+    }
+
+    /**
+     * Loads the message pattern from the resource bundle.
+     *
+     * @param resourceBundleName The {@link ResourceBundle} name from which to search the {@link KapuaErrorCode}.
+     * @param locale             The {@link Locale} of the {@link ResourceBundle}.
+     * @param code               The {@link KapuaErrorCode} to search in the {@link ResourceBundle}.
+     * @return The message pattern of the given {@link KapuaErrorCode} if found, {@code null} otherwise.
+     * @since 1.0.0
+     */
+    private static String getMessagePattern(@NotNull String resourceBundleName, @NotNull Locale locale, @NotNull KapuaErrorCode code) {
+
+        String messagePattern = null;
+        ResourceBundle resourceBundle;
+        try {
+            resourceBundle = ResourceBundle.getBundle(resourceBundleName, locale);
+        } catch (MissingResourceException mre) {
+            LOG.warn("Could not load exception messages for resource: {} in locale: {}. A generic error message will be printed.", resourceBundleName, locale);
+            return null;
+        }
+        try {
+            messagePattern = resourceBundle.getString(code.name());
+        } catch (MissingResourceException mre) {
+            LOG.warn("Could not load exception messages for code: {}. A generic error message will be printed.", code.name());
+        }
+
+        return messagePattern;
+    }
+}

service/api/src/main/java/org/eclipse/kapua/KapuaErrorCode.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2011, 2016 Eurotech and/or its affiliates and others
+ * Copyright (c) 2016, 2019 Eurotech and/or its affiliates and others
  *
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
@@ -11,17 +11,22 @@
  *******************************************************************************/
 package org.eclipse.kapua;
 
+import java.io.Serializable;
+
 /**
- * Kapua error code definition.
+ * {@link KapuaErrorCode} definition.
  *
- * @since 1.0
+ * @since 1.0.0
  */
-public interface KapuaErrorCode {
+public interface KapuaErrorCode extends Serializable {
 
     /**
-     * Get the error code name
+     * Gets the error code name.
+     * <p>
+     * The name can be used to search the exception message in the {@link java.util.ResourceBundle}.
      *
-     * @return
+     * @return The error code name.
+     * @since 1.0.0
      */
     String name();
 }