Remove some raw warnings from settings

Also sneaks in a couple of javadocs and one early return that I think makes
the method easier to read.

core/src/main/java/org/elasticsearch/common/settings/AbstractScopedSettings.java

@@ -36,7 +36,7 @@ import java.util.function.Consumer;
  */
 public abstract class AbstractScopedSettings extends AbstractComponent {
     private Settings lastSettingsApplied = Settings.EMPTY;
-    private final List<SettingUpdater> settingUpdaters = new ArrayList<>();
+    private final List<SettingUpdater<?>> settingUpdaters = new ArrayList<>();
     private final Map<String, Setting<?>> complexMatchers = new HashMap<>();
     private final Map<String, Setting<?>> keySettings = new HashMap<>();
     private final Setting.Scope scope;
@@ -68,7 +68,7 @@ public abstract class AbstractScopedSettings extends AbstractComponent {
         final Settings current = Settings.builder().put(this.settings).put(settings).build();
         final Settings previous = Settings.builder().put(this.settings).put(this.lastSettingsApplied).build();
         List<RuntimeException> exceptions = new ArrayList<>();
-        for (SettingUpdater settingUpdater : settingUpdaters) {
+        for (SettingUpdater<?> settingUpdater : settingUpdaters) {
             try {
                 if (settingUpdater.hasChanged(current, previous)) {
                     settingUpdater.getValue(current, previous);
@@ -99,7 +99,7 @@ public abstract class AbstractScopedSettings extends AbstractComponent {
         final Settings previous = Settings.builder().put(this.settings).put(this.lastSettingsApplied).build();
         try {
             List<Runnable> applyRunnables = new ArrayList<>();
-            for (SettingUpdater settingUpdater : settingUpdaters) {
+            for (SettingUpdater<?> settingUpdater : settingUpdaters) {
                 try {
                     applyRunnables.add(settingUpdater.updater(current, previous));
                 } catch (Exception ex) {
@@ -164,6 +164,7 @@ public abstract class AbstractScopedSettings extends AbstractComponent {
     /**
      * Transactional interface to update settings.
      * @see Setting
+     * @param <T> the type of the value of the setting
      */
     public interface SettingUpdater<T> {
 
@@ -216,17 +217,16 @@ public abstract class AbstractScopedSettings extends AbstractComponent {
     /**
      * Returns the {@link Setting} for the given key or <code>null</code> if the setting can not be found.
      */
-    public Setting get(String key) {
+    public Setting<?> get(String key) {
         Setting<?> setting = keySettings.get(key);
-        if (setting == null) {
+        if (setting != null) {
-            for (Map.Entry<String, Setting<?>> entry : complexMatchers.entrySet()) {
-                if (entry.getValue().match(key)) {
-                    return entry.getValue();
-                }
-            }
-        } else {
             return setting;
         }
+        for (Map.Entry<String, Setting<?>> entry : complexMatchers.entrySet()) {
+            if (entry.getValue().match(key)) {
+                return entry.getValue();
+            }
+        }
         return null;
     }
 
@@ -234,7 +234,7 @@ public abstract class AbstractScopedSettings extends AbstractComponent {
      * Returns <code>true</code> if the setting for the given key is dynamically updateable. Otherwise <code>false</code>.
      */
     public boolean hasDynamicSetting(String key) {
-        final Setting setting = get(key);
+        final Setting<?> setting = get(key);
         return setting != null && setting.isDynamic();
     }
 

core/src/main/java/org/elasticsearch/common/settings/Setting.java

@@ -42,6 +42,8 @@ import java.util.function.Function;
 import java.util.regex.Pattern;
 
 /**
+ * A setting. Encapsulates typical stuff like default value, parsing, and scope.
+ * Some (dynamic=true) can by modified at run time using the API.
  */
 public class Setting<T> extends ToXContentToBytes {
     private final String key;
@@ -173,11 +175,18 @@ public class Setting<T> extends ToXContentToBytes {
         INDEX;
     }
 
-    final AbstractScopedSettings.SettingUpdater newUpdater(Consumer<T> consumer, ESLogger logger) {
+    /**
+     * Build a new updater with a noop validator.
+     */
+    final AbstractScopedSettings.SettingUpdater<T> newUpdater(Consumer<T> consumer, ESLogger logger) {
         return newUpdater(consumer, logger, (s) -> {});
     }
 
-    AbstractScopedSettings.SettingUpdater newUpdater(Consumer<T> consumer, ESLogger logger, Consumer<T> validator) {
+    /**
+     * Build the updater responsible for validating new values, logging the new
+     * value, and eventually setting the value where it belongs.
+     */
+    AbstractScopedSettings.SettingUpdater<T> newUpdater(Consumer<T> consumer, ESLogger logger, Consumer<T> validator) {
         if (isDynamic()) {
             return new Updater(consumer, logger, validator);
         } else {
@@ -343,6 +352,7 @@ public class Setting<T> extends ToXContentToBytes {
                 return array == null ? defaultValue.apply(settings) : arrayToParsableString(array);
             }
 
+            @Override
             public boolean match(String toTest) {
                 return pattern.matcher(toTest).matches();
             }

core/src/test/java/org/elasticsearch/common/settings/SettingTests.java

@@ -45,7 +45,7 @@ public class SettingTests extends ESTestCase {
         ByteSizeValue byteSizeValue = byteSizeValueSetting.get(Settings.EMPTY);
         assertEquals(byteSizeValue.bytes(), 1024);
         AtomicReference<ByteSizeValue> value = new AtomicReference<>(null);
-        ClusterSettings.SettingUpdater settingUpdater = byteSizeValueSetting.newUpdater(value::set, logger);
+        ClusterSettings.SettingUpdater<ByteSizeValue> settingUpdater = byteSizeValueSetting.newUpdater(value::set, logger);
         try {
             settingUpdater.apply(Settings.builder().put("a.byte.size", 12).build(), Settings.EMPTY);
             fail("no unit");
@@ -60,7 +60,7 @@ public class SettingTests extends ESTestCase {
     public void testSimpleUpdate() {
         Setting<Boolean> booleanSetting = Setting.boolSetting("foo.bar", false, true, Setting.Scope.CLUSTER);
         AtomicReference<Boolean> atomicBoolean = new AtomicReference<>(null);
-        ClusterSettings.SettingUpdater settingUpdater = booleanSetting.newUpdater(atomicBoolean::set, logger);
+        ClusterSettings.SettingUpdater<Boolean> settingUpdater = booleanSetting.newUpdater(atomicBoolean::set, logger);
         Settings build = Settings.builder().put("foo.bar", false).build();
         settingUpdater.apply(build, Settings.EMPTY);
         assertNull(atomicBoolean.get());
@@ -94,8 +94,7 @@ public class SettingTests extends ESTestCase {
         Setting<Boolean> booleanSetting = Setting.boolSetting("foo.bar", false, true, Setting.Scope.CLUSTER);
         AtomicReference<Boolean> ab1 = new AtomicReference<>(null);
         AtomicReference<Boolean> ab2 = new AtomicReference<>(null);
-        ClusterSettings.SettingUpdater settingUpdater = booleanSetting.newUpdater(ab1::set, logger);
+        ClusterSettings.SettingUpdater<Boolean> settingUpdater = booleanSetting.newUpdater(ab1::set, logger);
-        ClusterSettings.SettingUpdater settingUpdater2 = booleanSetting.newUpdater(ab2::set, logger);
         settingUpdater.apply(Settings.builder().put("foo.bar", true).build(), Settings.EMPTY);
         assertTrue(ab1.get());
         assertNull(ab2.get());
@@ -120,7 +119,7 @@ public class SettingTests extends ESTestCase {
         assertFalse(setting.isGroupSetting());
         ref.set(setting.get(Settings.EMPTY));
         ComplexType type = ref.get();
-        ClusterSettings.SettingUpdater settingUpdater = setting.newUpdater(ref::set, logger);
+        ClusterSettings.SettingUpdater<ComplexType> settingUpdater = setting.newUpdater(ref::set, logger);
         assertFalse(settingUpdater.apply(Settings.EMPTY, Settings.EMPTY));
         assertSame("no update - type has not changed", type, ref.get());
 
@@ -147,7 +146,7 @@ public class SettingTests extends ESTestCase {
         AtomicReference<Settings> ref = new AtomicReference<>(null);
         Setting<Settings> setting = Setting.groupSetting("foo.bar.", true, Setting.Scope.CLUSTER);
         assertTrue(setting.isGroupSetting());
-        ClusterSettings.SettingUpdater settingUpdater = setting.newUpdater(ref::set, logger);
+        ClusterSettings.SettingUpdater<Settings> settingUpdater = setting.newUpdater(ref::set, logger);
 
         Settings currentInput = Settings.builder().put("foo.bar.1.value", "1").put("foo.bar.2.value", "2").put("foo.bar.3.value", "3").build();
         Settings previousInput = Settings.EMPTY;
@@ -191,7 +190,7 @@ public class SettingTests extends ESTestCase {
         assertTrue(setting.match("foo.bar.baz"));
         assertFalse(setting.match("foo.baz.bar"));
 
-        ClusterSettings.SettingUpdater predicateSettingUpdater = setting.newUpdater(ref::set, logger,(s) -> assertFalse(true));
+        ClusterSettings.SettingUpdater<Settings> predicateSettingUpdater = setting.newUpdater(ref::set, logger,(s) -> assertFalse(true));
         try {
             predicateSettingUpdater.apply(Settings.builder().put("foo.bar.1.value", "1").put("foo.bar.2.value", "2").build(), Settings.EMPTY);
             fail("not accepted");
@@ -273,7 +272,7 @@ public class SettingTests extends ESTestCase {
         assertArrayEquals(value.toArray(new String[0]), input.toArray(new String[0]));
 
         AtomicReference<List<String>> ref = new AtomicReference<>();
-        AbstractScopedSettings.SettingUpdater settingUpdater = listSetting.newUpdater(ref::set, logger);
+        AbstractScopedSettings.SettingUpdater<List<String>> settingUpdater = listSetting.newUpdater(ref::set, logger);
         assertTrue(settingUpdater.hasChanged(builder.build(), Settings.EMPTY));
         settingUpdater.apply(builder.build(), Settings.EMPTY);
         assertEquals(input.size(), ref.get().size());