HSEARCH-3776 Remove unnecessary hacks to support multiple data types …

…(integer and boolean) in IndexWriterSetting

backend/lucene/src/main/java/org/hibernate/search/backend/lucene/logging/impl/Log.java

@@ -660,4 +660,13 @@ SearchException uncommittedOperationsBecauseOfFailure(String causeMessage,
 			value = "Field '%1$s' is not contained in a nested object."
 					+ " Aggregation filters are only available if the field to aggregate on is contained in a nested object.")
 	SearchException cannotFilterAggregationOnRootDocumentField(String absoluteFieldPath, @Param EventContext context);
+
+	@Message(id = ID_OFFSET_2 + 123,
+			value = "IndexWriter setting '%1$s' cannot be set to '%2$s': %3$s")
+	SearchException illegalIndexWriterSetting(String settingName, Object settingValue, String message, @Cause Exception e);
+
+	@Message(id = ID_OFFSET_2 + 124,
+			value = "Merge policy setting '%1$s' cannot be set to '%2$s': %3$s")
+	SearchException illegalMergePolicySetting(String settingName, Object settingValue, String message, @Cause Exception e);
+
 }

backend/lucene/src/main/java/org/hibernate/search/backend/lucene/logging/impl/LuceneLogCategories.java

@@ -6,6 +6,7 @@
  */
 package org.hibernate.search.backend.lucene.logging.impl;
 
+import org.hibernate.search.backend.lucene.lowlevel.writer.impl.IndexWriterSettings;
 import org.hibernate.search.util.common.logging.impl.LogCategory;
 import org.hibernate.search.util.common.logging.impl.LoggerFactory;
 
@@ -25,8 +26,6 @@ private LuceneLogCategories() {
 	 * To enable the logger, the category needs to be enabled at TRACE level and configuration
 	 * property {@code org.hibernate.search.backend.configuration.impl.IndexWriterSetting#INFOSTREAM}
 	 * needs to be enabled on the index.
-	 *
-	 * @see org.hibernate.search.backend.lucene.lowlevel.writer.impl.IndexWriterSetting#INFOSTREAM
 	 */
 	public static final LogCategory INFOSTREAM_LOGGER_CATEGORY = new LogCategory( "org.hibernate.search.backend.lucene.infostream" );
 

backend/lucene/src/main/java/org/hibernate/search/backend/lucene/lowlevel/writer/impl/IndexWriterSettingValue.java

@@ -0,0 +1,67 @@
+/*
+ * Hibernate Search, full-text search for your domain model
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.search.backend.lucene.lowlevel.writer.impl;
+
+import java.lang.invoke.MethodHandles;
+import java.util.function.BiConsumer;
+
+import org.hibernate.search.backend.lucene.logging.impl.Log;
+import org.hibernate.search.util.common.SearchException;
+import org.hibernate.search.util.common.logging.impl.LoggerFactory;
+
+import org.apache.lucene.index.IndexWriterConfig;
+import org.apache.lucene.index.LogByteSizeMergePolicy;
+
+class IndexWriterSettingValue<T> {
+
+	private static final Log log = LoggerFactory.make( Log.class, MethodHandles.lookup() );
+
+	private final String settingName;
+	private final T value;
+	private final BiConsumer<IndexWriterConfig, T> writerSettingApplier;
+	private final BiConsumer<LogByteSizeMergePolicy, T> mergePolicySettingApplier;
+
+	IndexWriterSettingValue(String settingName, T value,
+			BiConsumer<IndexWriterConfig, T> writerSettingApplier,
+			BiConsumer<LogByteSizeMergePolicy, T> mergePolicySettingApplier) {
+		this.settingName = settingName;
+		this.value = value;
+		this.writerSettingApplier = writerSettingApplier;
+		this.mergePolicySettingApplier = mergePolicySettingApplier;
+	}
+
+	@Override
+	public String toString() {
+		return "<" + settingName + "=" + value + ">";
+	}
+
+	/**
+	 * @param writerConfig the {@link IndexWriterConfig}
+	 * @throws SearchException when user selects an invalid value.
+	 */
+	public void applySetting(IndexWriterConfig writerConfig) {
+		try {
+			writerSettingApplier.accept( writerConfig, value );
+		}
+		catch (RuntimeException e) {
+			throw log.illegalIndexWriterSetting( settingName, value, e.getMessage(), e );
+		}
+	}
+
+	/**
+	 * @param logByteSizeMergePolicy the {@link LogByteSizeMergePolicy}
+	 * @throws SearchException when user selects an invalid value.
+	 */
+	public void applySetting(LogByteSizeMergePolicy logByteSizeMergePolicy) {
+		try {
+			mergePolicySettingApplier.accept( logByteSizeMergePolicy, value );
+		}
+		catch (RuntimeException e) {
+			throw log.illegalMergePolicySetting( settingName, value, e.getMessage(), e );
+		}
+	}
+}