Refactor configuration API to add single Configurable interface and A…

…bstractConfigurable as a utility class.

api/src/main/java/net/kuujo/copycat/CopycatConfig.java

@@ -31,7 +31,7 @@
  *
  * @author <a href="http://github.com/kuujo">Jordan Halterman</a>
  */
-public class CopycatConfig extends Config {
+public class CopycatConfig extends AbstractConfigurable {
   public static final String COPYCAT_SERIALIZER = "serializer";
   public static final String COPYCAT_CLUSTER = "cluster";
   public static final String COPYCAT_RESOURCES = "resources";
@@ -46,7 +46,7 @@ public CopycatConfig(Map<String, Object> config) {
     super(config);
   }
 
-  public CopycatConfig(Config config) {
+  private CopycatConfig(CopycatConfig config) {
     super(config);
   }
 
@@ -155,7 +155,7 @@ public Map<String, ResourceConfig> getResourceConfigs() {
     Map<String, Map<String, Object>> resources = get(COPYCAT_RESOURCES, new HashMap<>(0));
     Map<String, ResourceConfig> configs = new HashMap<>(resources.size());
     for (Map.Entry<String, Map<String, Object>> entry : resources.entrySet()) {
-      configs.put(entry.getKey(), load(entry.getValue()));
+      configs.put(entry.getKey(), Configurable.load(entry.getValue()));
     }
     return configs;
   }

collections/src/main/java/net/kuujo/copycat/collections/AsyncCollectionConfig.java

@@ -15,7 +15,6 @@
  */
 package net.kuujo.copycat.collections;
 
-import net.kuujo.copycat.Config;
 import net.kuujo.copycat.ResourceConfig;
 
 import java.util.Map;
@@ -34,7 +33,7 @@ protected AsyncCollectionConfig(Map<String, Object> config) {
     super(config);
   }
 
-  protected AsyncCollectionConfig(Config config) {
+  protected AsyncCollectionConfig(T config) {
     super(config);
   }
 

collections/src/main/java/net/kuujo/copycat/collections/AsyncListConfig.java

@@ -15,7 +15,6 @@
  */
 package net.kuujo.copycat.collections;
 
-import net.kuujo.copycat.Config;
 import net.kuujo.copycat.StateLogConfig;
 import net.kuujo.copycat.cluster.ClusterConfig;
 import net.kuujo.copycat.cluster.coordinator.CoordinatedResourceConfig;
@@ -38,7 +37,7 @@ public AsyncListConfig(Map<String, Object> config) {
     super(config);
   }
 
-  protected AsyncListConfig(Config config) {
+  protected AsyncListConfig(AsyncListConfig config) {
     super(config);
   }
 

collections/src/main/java/net/kuujo/copycat/collections/AsyncLockConfig.java

@@ -15,7 +15,6 @@
  */
 package net.kuujo.copycat.collections;
 
-import net.kuujo.copycat.Config;
 import net.kuujo.copycat.ResourceConfig;
 import net.kuujo.copycat.StateLogConfig;
 import net.kuujo.copycat.cluster.ClusterConfig;
@@ -39,7 +38,7 @@ public AsyncLockConfig(Map<String, Object> config) {
     super(config);
   }
 
-  public AsyncLockConfig(Config config) {
+  protected AsyncLockConfig(AsyncLockConfig config) {
     super(config);
   }
 

collections/src/main/java/net/kuujo/copycat/collections/AsyncMapConfig.java

@@ -15,7 +15,6 @@
  */
 package net.kuujo.copycat.collections;
 
-import net.kuujo.copycat.Config;
 import net.kuujo.copycat.ResourceConfig;
 import net.kuujo.copycat.StateLogConfig;
 import net.kuujo.copycat.cluster.ClusterConfig;
@@ -39,7 +38,7 @@ public AsyncMapConfig(Map<String, Object> config) {
     super(config);
   }
 
-  public AsyncMapConfig(Config config) {
+  protected AsyncMapConfig(AsyncMapConfig config) {
     super(config);
   }
 

collections/src/main/java/net/kuujo/copycat/collections/AsyncMultiMapConfig.java

@@ -15,7 +15,6 @@
  */
 package net.kuujo.copycat.collections;
 
-import net.kuujo.copycat.Config;
 import net.kuujo.copycat.ResourceConfig;
 import net.kuujo.copycat.StateLogConfig;
 import net.kuujo.copycat.cluster.ClusterConfig;
@@ -39,7 +38,7 @@ public AsyncMultiMapConfig(Map<String, Object> config) {
     super(config);
   }
 
-  public AsyncMultiMapConfig(Config config) {
+  protected AsyncMultiMapConfig(AsyncMultiMapConfig config) {
     super(config);
   }
 

collections/src/main/java/net/kuujo/copycat/collections/AsyncSetConfig.java

@@ -15,7 +15,6 @@
  */
 package net.kuujo.copycat.collections;
 
-import net.kuujo.copycat.Config;
 import net.kuujo.copycat.StateLogConfig;
 import net.kuujo.copycat.cluster.ClusterConfig;
 import net.kuujo.copycat.cluster.coordinator.CoordinatedResourceConfig;
@@ -38,7 +37,7 @@ public AsyncSetConfig(Map<String, Object> config) {
     super(config);
   }
 
-  public AsyncSetConfig(Config config) {
+  protected AsyncSetConfig(AsyncSetConfig config) {
     super(config);
   }
 

core/src/main/java/net/kuujo/copycat/Config.java → core/src/main/java/net/kuujo/copycat/AbstractConfigurable.java

@@ -17,82 +17,67 @@
 
 import net.kuujo.copycat.internal.util.Assert;
 
-import java.lang.reflect.Constructor;
-import java.lang.reflect.InvocationTargetException;
-import java.util.*;
-import java.util.function.Consumer;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
 
 /**
  * Base configuration for configurable types.
  *
  * @author <a href="http://github.com/kuujo">Jordan Halterman</a>
  */
-public class Config implements Copyable<Config>, Iterable<Map.Entry<String, Object>> {
+public abstract class AbstractConfigurable implements Configurable {
   public static final String CONFIG_CLASS = "class";
-  private final Map<String, Object> config;
+  private Map<String, Object> config;
 
-  public Config() {
+  protected AbstractConfigurable() {
     this(new HashMap<>(128));
   }
 
-  public Config(Map<String, Object> config) {
+  protected AbstractConfigurable(Map<String, Object> config) {
     this.config = config;
   }
 
-  protected Config(Config config) {
-    this(new HashMap<>(config.config));
+  protected AbstractConfigurable(Configurable config) {
+    this(config.toMap());
   }
 
-  /**
-   * Loads a configuration object from the given configuration map.
-   *
-   * @param config The configuration map from which to load the configuration object.
-   * @param <T> The configuration object type.
-   * @return The loaded configuration object.
-   */
-  @SuppressWarnings("unchecked")
-  protected static <T extends Config> T load(Map<String, Object> config) {
-    String className = (String) config.get(CONFIG_CLASS);
-    if (className == null) {
-      return (T) new Config(config);
-    }
+  @Override
+  public Configurable copy() {
     try {
-      Class<?> clazz = Class.forName(className);
-      Constructor<?> constructor = clazz.getConstructor(Map.class);
-      return (T) constructor.newInstance(config);
-    } catch (ClassNotFoundException | NoSuchMethodException e) {
-      throw new ConfigurationException("Invalid configuration class", e);
-    } catch (InstantiationException | IllegalAccessException | InvocationTargetException | ClassCastException e) {
-      throw new ConfigurationException("Failed to instantiate configuration object", e);
+      Configurable copy = getClass().newInstance();
+      copy.configure(toMap());
+      return copy;
+    } catch (InstantiationException | IllegalAccessException e) {
+      throw new ConfigurationException("Failed to create configuration copy", e);
     }
   }
 
   @Override
-  public Config copy() {
-    return new Config(this);
+  public void configure(Map<String, Object> config) {
+    this.config = config;
   }
 
   /**
    * Puts a configuration value in the configuration.
    *
    * @param key The configuration key.
    * @param value The configuration value.
-   * @return The configuration instance.
    */
-  public Config put(String key, Object value) {
-    config.put(Assert.isNotNull(key, "key"), value instanceof Config ? ((Config) value).toMap() : value);
-    return this;
+  @SuppressWarnings("unchecked")
+  protected void put(String key, Object value) {
+    config.put(Assert.isNotNull(key, "key"), value instanceof Configurable ? ((Configurable) value).toMap() : value);
   }
 
   /**
    * Gets a configuration value from the configuration.
    *
    * @param key The configuration key.
-   * @param <T> The configuration value type.
+   * @param <U> The configuration value type.
    * @return The configuration value.
    */
   @SuppressWarnings("unchecked")
-  public <T> T get(String key) {
+  protected <U> U get(String key) {
     return get(key, null);
   }
 
@@ -101,34 +86,34 @@ public <T> T get(String key) {
    *
    * @param key The configuration key.
    * @param defaultValue The default value to return if the configuration does not exist.
-   * @param <T> The configuration type.
+   * @param <U> The configuration type.
    * @return The configuration value.
    */
   @SuppressWarnings("unchecked")
-  public <T> T get(String key, T defaultValue) {
+  protected <U> U get(String key, U defaultValue) {
     Assert.isNotNull(key, "key");
-    Object value = config.containsKey(key) ? (T) config.get(key) : defaultValue;
+    Object value = config.containsKey(key) ? config.get(key) : defaultValue;
     if (value == null) {
       return null;
     } else if (value instanceof Map) {
       String className = (String) ((Map<?, ?>) value).get(CONFIG_CLASS);
       if (className != null) {
-        return (T) load((Map<String, Object>) value);
+        return (U) Configurable.load((Map<String, Object>) value);
       }
     }
-    return (T) value;
+    return (U) value;
   }
 
   /**
    * Removes a configuration value from the configuration.
    *
    * @param key The configuration key.
-   * @param <T> The configuration value type.
+   * @param <U> The configuration value type.
    * @return The configuration value that was removed.
    */
   @SuppressWarnings("unchecked")
-  public <T> T remove(String key) {
-    return (T) config.remove(Assert.isNotNull(key, "key"));
+  protected <U> U remove(String key) {
+    return (U) config.remove(Assert.isNotNull(key, "key"));
   }
 
   /**
@@ -137,7 +122,7 @@ public <T> T remove(String key) {
    * @param key The key to check.
    * @return Indicates whether the configuration contains the given key.
    */
-  public boolean containsKey(String key) {
+  protected boolean containsKey(String key) {
     return config.containsKey(Assert.isNotNull(key, "key"));
   }
 
@@ -146,7 +131,7 @@ public boolean containsKey(String key) {
    *
    * @return The configuration key set.
    */
-  public Set<String> keySet() {
+  protected Set<String> keySet() {
     return config.keySet();
   }
 
@@ -155,40 +140,19 @@ public Set<String> keySet() {
    *
    * @return The configuration entry set.
    */
-  public Set<Map.Entry<String, Object>> entrySet() {
+  protected Set<Map.Entry<String, Object>> entrySet() {
     return config.entrySet();
   }
 
   /**
    * Clears the configuration.
-   *
-   * @return The configuration instance.
    */
-  public Config clear() {
+  @SuppressWarnings("unchecked")
+  protected void clear() {
     config.clear();
-    return this;
   }
 
   @Override
-  public Iterator<Map.Entry<String, Object>> iterator() {
-    return config.entrySet().iterator();
-  }
-
-  @Override
-  public void forEach(Consumer<? super Map.Entry<String, Object>> action) {
-    config.entrySet().forEach(action);
-  }
-
-  @Override
-  public Spliterator<Map.Entry<String, Object>> spliterator() {
-    return config.entrySet().spliterator();
-  }
-
-  /**
-   * Returns the configuration as a map.
-   *
-   * @return The configuration map.
-   */
   public Map<String, Object> toMap() {
     Map<String, Object> config = new HashMap<>(this.config);
     config.put("class", getClass().getName());