Added part of the 'String Commands' group to RedisClient as specified on the official Redis website.

java/client/src/main/java/glide/api/BaseClient.java

@@ -65,6 +65,60 @@ protected static String handleStringResponse(Response response) {
                         + " expected String");
     }
 
+    /**
+     * Extracts the response value from the Redis response and either throws an exception or returns
+     * the value as a Long.
+     *
+     * @param response Redis protobuf message
+     * @return Response as a Long
+     */
+    protected static Long handleLongResponse(Response response) {
+        Object value = handleObjectResponse(response);
+        if (value instanceof Long) {
+            return (Long) value;
+        }
+        throw new RedisException(
+                "Unexpected return type from Redis: got "
+                        + value.getClass().getSimpleName()
+                        + " expected Long");
+    }
+
+    /**
+     * Extracts the response value from the Redis response and either throws an exception or returns
+     * the value as a Double.
+     *
+     * @param response Redis protobuf message
+     * @return Response as a Double
+     */
+    protected static Double handleDoubleResponse(Response response) {
+        Object value = handleObjectResponse(response);
+        if (value instanceof Double) {
+            return (Double) value;
+        }
+        throw new RedisException(
+                "Unexpected return type from Redis: got "
+                        + value.getClass().getSimpleName()
+                        + " expected Double");
+    }
+
+    /**
+     * Extracts the response value from the Redis response and either throws an exception or returns
+     * the value as an Object Array.
+     *
+     * @param response Redis protobuf message
+     * @return Response as an Object Array
+     */
+    protected static Object[] handleObjectArrayResponse(Response response) {
+        Object value = handleObjectResponse(response);
+        if (value instanceof Object[]) {
+            return (Object[]) value;
+        }
+        throw new RedisException(
+                "Unexpected return type from Redis: got "
+                        + value.getClass().getSimpleName()
+                        + " expected Object Array");
+    }
+
     /**
      * Extracts the response value from the Redis response and either throws an exception or returns
      * the * value as a HashMap

java/client/src/main/java/glide/api/RedisClient.java

@@ -15,6 +15,8 @@
 import glide.managers.CommandManager;
 import glide.managers.ConnectionManager;
 import glide.managers.models.Command;
+import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.CompletableFuture;
@@ -29,8 +31,8 @@ public class RedisClient extends BaseClient
     /**
      * Request an async (non-blocking) Redis client in Standalone mode.
      *
-     * @param config - Redis Client Configuration
-     * @return a Future to connect and return a RedisClient
+     * @param config Redis Client Configuration
+     * @return A Future to connect and return a RedisClient
      */
     public static CompletableFuture<RedisClient> CreateClient(RedisClientConfiguration config) {
         try {
@@ -79,8 +81,8 @@ protected RedisClient(ConnectionManager connectionManager, CommandManager comman
      * Object result = client.customCommand(new String[]{"CLIENT","LIST","TYPE", "PUBSUB"}).get();
      * </pre>
      *
-     * @param args arguments for the custom command
-     * @return a CompletableFuture with response result from Redis
+     * @param args Arguments for the custom command
+     * @return A CompletableFuture with response result from Redis
      */
     public CompletableFuture<Object> customCommand(String[] args) {
         Command command =
@@ -92,7 +94,7 @@ public CompletableFuture<Object> customCommand(String[] args) {
      * Ping the Redis server.
      *
      * @see <a href="https://redis.io/commands/ping/">redis.io</a> for details.
-     * @returns the String "PONG"
+     * @return The String "PONG"
      */
     @Override
     public CompletableFuture<String> ping() {
@@ -104,8 +106,8 @@ public CompletableFuture<String> ping() {
      * Ping the Redis server.
      *
      * @see <a href="https://redis.io/commands/ping/">redis.io</a> for details.
-     * @param msg - the ping argument that will be returned.
-     * @returns return a copy of the argument.
+     * @param msg The ping argument that will be returned.
+     * @return Return a copy of the argument.
      */
     @Override
     public CompletableFuture<String> ping(String msg) {
@@ -133,7 +135,7 @@ public CompletableFuture<Map> info() {
      * Get information and statistics about the Redis server.
      *
      * @see <a href="https://redis.io/commands/info/">redis.io</a> for details.
-     * @param options - A list of InfoSection values specifying which sections of information to
+     * @param options A list of InfoSection values specifying which sections of information to
      *     retrieve. When no parameter is provided, the default option is assumed.
      * @return CompletableFuture with the response
      */
@@ -151,7 +153,7 @@ public CompletableFuture<Map> info(InfoOptions options) {
      * Get the value associated with the given key, or null if no such value exists.
      *
      * @see <a href="https://redis.io/commands/get/">redis.io</a> for details.
-     * @param key - The key to retrieve from the database.
+     * @param key The key to retrieve from the database.
      * @return If `key` exists, returns the value of `key` as a string. Otherwise, return null
      */
     @Override
@@ -168,9 +170,9 @@ public CompletableFuture<String> get(String key) {
      * Set the given key with the given value.
      *
      * @see <a href="https://redis.io/commands/set/">redis.io</a> for details.
-     * @param key - The key to store.
-     * @param value - The value to store with the given key.
-     * @return null
+     * @param key The key to store.
+     * @param value The value to store with the given key.
+     * @return An empty response on success
      */
     @Override
     public CompletableFuture<Void> set(String key, String value) {
@@ -186,10 +188,10 @@ public CompletableFuture<Void> set(String key, String value) {
      * Set the given key with the given value. Return value is dependent on the passed options.
      *
      * @see <a href="https://redis.io/commands/set/">redis.io</a> for details.
-     * @param key - The key to store.
-     * @param value - The value to store with the given key.
-     * @param options - The Set options
-     * @return string or null If value isn't set because of `onlyIfExists` or `onlyIfDoesNotExist`
+     * @param key The key to store.
+     * @param value The value to store with the given key.
+     * @param options The Set options
+     * @return String or null If value isn't set because of `onlyIfExists` or `onlyIfDoesNotExist`
      *     conditions, return null. If `returnOldValue` is set, return the old value as a string.
      */
     @Override
@@ -201,4 +203,144 @@ public CompletableFuture<String> set(String key, String value, SetOptions option
                         .build();
         return commandManager.submitNewCommand(command, BaseClient::handleStringResponse);
     }
+
+    /**
+     * Decrements the number stored at `key` by one. If `key` does not exist, it is set to 0 before
+     * performing the operation.
+     *
+     * @see <a href="https://redis.io/commands/decr/">redis.io</a> for details.
+     * @param key The key to decrement its value.
+     * @return The value of `key` after the decrement. An error is raised if `key` contains a value of
+     *     the wrong type or contains a string that can not be represented as a long.
+     */
+    @Override
+    public CompletableFuture<Long> decr(String key) {
+        Command command =
+                Command.builder()
+                        .requestType(Command.RequestType.DECR)
+                        .arguments(new String[] {key})
+                        .build();
+        return commandManager.submitNewCommand(command, BaseClient::handleLongResponse);
+    }
+
+    /**
+     * Decrements the number stored at `key` by `amount`. If `key` does not exist, it is set to 0
+     * before performing the operation.
+     *
+     * @see <a href="https://redis.io/commands/decrby/">redis.io</a> for details.
+     * @param key The key to decrement its value.
+     * @param amount The amount to decrement.
+     * @return The value of `key` after the decrement. An error is raised if `key` contains a value of
+     *     the wrong type or contains a string that can not be represented as long.
+     */
+    @Override
+    public CompletableFuture<Long> decrBy(String key, long amount) {
+        Command command =
+                Command.builder()
+                        .requestType(Command.RequestType.DECR_BY)
+                        .arguments(new String[] {key, Long.toString(amount)})
+                        .build();
+        return commandManager.submitNewCommand(command, BaseClient::handleLongResponse);
+    }
+
+    /**
+     * Increments the number stored at `key` by one. If `key` does not exist, it is set to 0 before
+     * performing the operation.
+     *
+     * @see <a href="https://redis.io/commands/incr/">redis.io</a> for details.
+     * @param key The key to increment its value.
+     * @return The value of `key` after the increment, An error is raised if `key` contains a value of
+     *     the wrong type or contains a string that can not be represented as long.
+     */
+    @Override
+    public CompletableFuture<Long> incr(String key) {
+        Command command =
+                Command.builder()
+                        .requestType(Command.RequestType.INCR)
+                        .arguments(new String[] {key})
+                        .build();
+        return commandManager.submitNewCommand(command, BaseClient::handleLongResponse);
+    }
+
+    /**
+     * Increments the number stored at `key` by `amount`. If `key` does not exist, it is set to 0
+     * before performing the operation.
+     *
+     * @see <a href="https://redis.io/commands/incrby/">redis.io</a> for details.
+     * @param key The key to increment its value.
+     * @param amount The amount to increment.
+     * @return The value of `key` after the increment, An error is raised if `key` contains a value of
+     *     the wrong type or contains a string that can not be represented as long.
+     */
+    @Override
+    public CompletableFuture<Long> incrBy(String key, long amount) {
+        Command command =
+                Command.builder()
+                        .requestType(Command.RequestType.INCR_BY)
+                        .arguments(new String[] {key, Long.toString(amount)})
+                        .build();
+        return commandManager.submitNewCommand(command, BaseClient::handleLongResponse);
+    }
+
+    /**
+     * Increment the string representing a floating point number stored at `key` by `amount`. By using
+     * a negative increment value, the result is that the value stored at `key` is decremented. If
+     * `key` does not exist, it is set to 0 before performing the operation.
+     *
+     * @see <a href="https://redis.io/commands/incrbyfloat/">redis.io</a> for details.
+     * @param key The key to increment its value.
+     * @param amount The amount to increment.
+     * @return The value of `key` after the increment. An error is raised if `key` contains a value of
+     *     the wrong type, or the current key content is not parsable as a double precision floating
+     *     point number.
+     */
+    @Override
+    public CompletableFuture<Double> incrByFloat(String key, double amount) {
+        Command command =
+                Command.builder()
+                        .requestType(Command.RequestType.INCR_BY_FLOAT)
+                        .arguments(new String[] {key, Double.toString(amount)})
+                        .build();
+        return commandManager.submitNewCommand(command, BaseClient::handleDoubleResponse);
+    }
+
+    /**
+     * Retrieve the values of multiple keys.
+     *
+     * @see <a href="https://redis.io/commands/mget/">redis.io</a> for details.
+     * @param keys An array of keys to retrieve values for.
+     * @return An array of values corresponding to the provided keys. If a key is not found, its
+     *     corresponding value in the array will be null.
+     */
+    @Override
+    public CompletableFuture<String[]> mget(String[] keys) {
+        Command command =
+                Command.builder().requestType(Command.RequestType.MGET).arguments(keys).build();
+        return commandManager
+                .submitNewCommand(command, BaseClient::handleObjectArrayResponse)
+                .thenApply(objects -> (String[]) objects);
+    }
+
+    /**
+     * Set multiple keys to multiple values in a single operation.
+     *
+     * @see <a href="https://redis.io/commands/mset/">redis.io</a> for details.
+     * @param keyValueMap A key-value map consisting of keys and their respective values to set.
+     * @return An empty response on success
+     */
+    @Override
+    public CompletableFuture<Void> mset(HashMap<String, String> keyValueMap) {
+        List<String> flatMap = new ArrayList<>();
+
+        for (Map.Entry<String, String> entry : keyValueMap.entrySet()) {
+            flatMap.add(entry.getKey());
+            flatMap.add(entry.getValue());
+        }
+
+        String[] args = flatMap.toArray(new String[0]);
+
+        Command command =
+                Command.builder().requestType(Command.RequestType.MSET).arguments(args).build();
+        return commandManager.submitNewCommand(command, BaseClient::handleVoidResponse);
+    }
 }

java/client/src/main/java/glide/api/commands/StringCommands.java

@@ -1,14 +1,33 @@
 package glide.api.commands;
 
 import glide.api.models.commands.SetOptions;
+import java.util.HashMap;
 import java.util.concurrent.CompletableFuture;
 
-/** String Commands interface to handle single commands that return Strings. */
+/**
+ * Commands that perform string manipulation.
+ *
+ * @see: <a href="https://redis.io/commands/?group=string">String Commands</a>
+ */
 public interface StringCommands {
 
     CompletableFuture<String> get(String key);
 
     CompletableFuture<Void> set(String key, String value);
 
     CompletableFuture<String> set(String key, String value, SetOptions options);
+
+    CompletableFuture<Long> decr(String key);
+
+    CompletableFuture<Long> decrBy(String key, long amount);
+
+    CompletableFuture<Long> incr(String key);
+
+    CompletableFuture<Long> incrBy(String key, long amount);
+
+    CompletableFuture<Double> incrByFloat(String key, double amount);
+
+    CompletableFuture<String[]> mget(String[] keys);
+
+    CompletableFuture<Void> mset(HashMap<String, String> keyValueMap);
 }

java/client/src/main/java/glide/managers/CommandManager.java

@@ -76,6 +76,20 @@ private RequestType mapRequestTypes(Command.RequestType inType) {
                 return RequestType.GetString;
             case SET_STRING:
                 return RequestType.SetString;
+            case DECR:
+                return RequestType.Decr;
+            case DECR_BY:
+                return RequestType.DecrBy;
+            case INCR:
+                return RequestType.Incr;
+            case INCR_BY:
+                return RequestType.IncrBy;
+            case INCR_BY_FLOAT:
+                return RequestType.IncrByFloat;
+            case MGET:
+                return RequestType.MGet;
+            case MSET:
+                return RequestType.MSet;
         }
         throw new RuntimeException("Unsupported request type");
     }