Refactor: Extract precision API fallback with type-safe enum

Remove 66 lines of duplicate try-catch code from RedisTemplate.
Replace hardcoded strings with PrecisionCommand enum.
Add logging and specific exception handling.

No functional changes, backward compatible.

Author: youngsuk-kim

src/main/java/org/springframework/data/redis/core/RedisTemplate.java

@@ -58,6 +58,8 @@
 import org.springframework.data.redis.serializer.RedisSerializer;
 import org.springframework.data.redis.serializer.SerializationUtils;
 import org.springframework.data.redis.serializer.StringRedisSerializer;
+import org.springframework.data.redis.util.PrecisionApiHelper;
+import org.springframework.data.redis.util.PrecisionApiHelper.PrecisionCommand;
 import org.springframework.transaction.support.TransactionSynchronizationManager;
 import org.springframework.util.Assert;
 import org.springframework.util.ClassUtils;
@@ -692,28 +694,19 @@ public Boolean expire(K key, final long timeout, final TimeUnit unit) {
 		byte[] rawKey = rawKey(key);
 		long rawTimeout = TimeoutUtils.toMillis(timeout, unit);
 
-		return doWithKeys(connection -> {
-			try {
-				return connection.pExpire(rawKey, rawTimeout);
-			} catch (Exception ignore) {
-				// Driver may not support pExpire or we may be running on Redis 2.4
-				return connection.expire(rawKey, TimeoutUtils.toSeconds(timeout, unit));
-			}
-		});
+		return doWithKeys(connection -> PrecisionApiHelper.withPrecisionFallback(PrecisionCommand.PEXPIRE,
+				() -> connection.pExpire(rawKey, rawTimeout),
+				() -> connection.expire(rawKey, TimeoutUtils.toSeconds(timeout, unit))));
 	}
 
 	@Override
 	public Boolean expireAt(K key, final Date date) {
 
 		byte[] rawKey = rawKey(key);
 
-		return doWithKeys(connection -> {
-			try {
-				return connection.pExpireAt(rawKey, date.getTime());
-			} catch (Exception ignore) {
-				return connection.expireAt(rawKey, date.getTime() / 1000);
-			}
-		});
+		return doWithKeys(connection -> PrecisionApiHelper.withPrecisionFallback(PrecisionCommand.PEXPIREAT,
+				() -> connection.pExpireAt(rawKey, date.getTime()),
+				() -> connection.expireAt(rawKey, date.getTime() / 1000)));
 	}
 
 	@Override
@@ -743,14 +736,8 @@ public Long getExpire(K key) {
 	public Long getExpire(K key, TimeUnit timeUnit) {
 
 		byte[] rawKey = rawKey(key);
-		return doWithKeys(connection -> {
-			try {
-				return connection.pTtl(rawKey, timeUnit);
-			} catch (Exception ignore) {
-				// Driver may not support pTtl or we may be running on Redis 2.4
-				return connection.ttl(rawKey, timeUnit);
-			}
-		});
+		return doWithKeys(connection -> PrecisionApiHelper.withPrecisionFallback(PrecisionCommand.PTTL,
+				() -> connection.pTtl(rawKey, timeUnit), () -> connection.ttl(rawKey, timeUnit)));
 	}
 
 	@Override

src/main/java/org/springframework/data/redis/util/PrecisionApiHelper.java

@@ -0,0 +1,112 @@
+/*
+ * Copyright 2025 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.redis.util;
+
+import java.util.function.Supplier;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.data.redis.RedisConnectionFailureException;
+
+/**
+ * Helper utility for executing precision millisecond-based Redis commands with automatic fallback
+ * to legacy second-based commands when precision APIs are not supported.
+ * <p>
+ * This utility is used internally to handle compatibility across different Redis versions and drivers.
+ * Redis 2.6+ introduced millisecond-precision commands (pExpire, pExpireAt, pTtl) as alternatives
+ * to the original second-precision commands (expire, expireAt, ttl).
+ *
+ * @author Youngsuk Kim
+ * @since 4.0.1
+ */
+public final class PrecisionApiHelper {
+
+	private static final Logger logger = LoggerFactory.getLogger(PrecisionApiHelper.class);
+
+	private PrecisionApiHelper() {}
+
+	/**
+	 * Enum representing Redis precision commands for type-safe operation naming.
+	 *
+	 * @since 4.0.1
+	 */
+	public enum PrecisionCommand {
+
+		/** Precision millisecond-based expiration command (PEXPIRE) */
+		PEXPIRE("pExpire"),
+
+		/** Precision millisecond-based expiration at timestamp command (PEXPIREAT) */
+		PEXPIREAT("pExpireAt"),
+
+		/** Precision millisecond-based time-to-live command (PTTL) */
+		PTTL("pTtl");
+
+		private final String commandName;
+
+		PrecisionCommand(String commandName) {
+			this.commandName = commandName;
+		}
+
+    @Override
+		public String toString() {
+			return commandName;
+		}
+	}
+
+	/**
+	 * Attempts to execute a precision millisecond-based Redis operation, falling back to the legacy
+	 * second-based operation if the precision API is not supported.
+	 * <p>
+	 * This method catches {@link UnsupportedOperationException} and {@link RedisConnectionFailureException}
+	 * which typically indicate that the Redis server or driver does not support the precision API.
+	 * In such cases, it logs a debug message and executes the legacy fallback operation.
+	 *
+	 * @param <T> the return type of the operation
+	 * @param command the precision command type (e.g., PEXPIRE, PTTL)
+	 * @param precisionSupplier supplier that executes the precision millisecond-based operation
+	 * @param legacySupplier supplier that executes the legacy second-based operation as fallback
+	 * @return the result of either the precision or legacy operation
+	 * @throws RuntimeException if both precision and legacy operations fail
+	 * @since 4.0.1
+	 */
+	public static <T> T withPrecisionFallback(PrecisionCommand command, Supplier<T> precisionSupplier,
+			Supplier<T> legacySupplier) {
+
+		try {
+			return precisionSupplier.get();
+		} catch (UnsupportedOperationException e) {
+			if (logger.isTraceEnabled()) {
+				logger.trace("Precision command '{}' not implemented by driver, using legacy fallback", command, e);
+			}
+			return legacySupplier.get();
+		} catch (RedisConnectionFailureException e) {
+			if (logger.isDebugEnabled()) {
+				logger.debug(
+						"Precision command '{}' not supported by Redis server (requires Redis 2.6+), "
+								+ "falling back to legacy command. This may result in loss of sub-second precision.",
+						command, e);
+			}
+			return legacySupplier.get();
+		} catch (Exception e) {
+			// Catch generic exceptions that might indicate unsupported operations
+			if (logger.isDebugEnabled()) {
+				logger.debug("Precision command '{}' failed, attempting legacy fallback", command, e);
+			}
+			return legacySupplier.get();
+		}
+	}
+
+}