Update chat memory example and separate ChatMemoryStore from ChatMemory usage

docs/modules/ROOT/examples/io/quarkiverse/langchain4j/samples/ChatMemoryProviderBean.java

@@ -0,0 +1,25 @@
+package io.quarkiverse.langchain4j.samples;
+
+import jakarta.enterprise.context.ApplicationScoped;
+import jakarta.inject.Inject;
+
+import dev.langchain4j.memory.ChatMemory;
+import dev.langchain4j.memory.chat.ChatMemoryProvider;
+import dev.langchain4j.memory.chat.MessageWindowChatMemory;
+import dev.langchain4j.store.memory.chat.ChatMemoryStore;
+
+@ApplicationScoped
+public class ChatMemoryProviderBean implements ChatMemoryProvider {
+
+    @Inject
+    ChatMemoryStore store;
+
+    @Override
+    public ChatMemory get(Object memoryId) {
+        return MessageWindowChatMemory.builder()
+                .id(memoryId)
+                .maxMessages(20)
+                .chatMemoryStore(store)
+                .build();
+    }
+}

docs/modules/ROOT/examples/io/quarkiverse/langchain4j/samples/ChatMemoryStoreProducer.java

@@ -0,0 +1,14 @@
+package io.quarkiverse.langchain4j.samples;
+
+import jakarta.enterprise.context.ApplicationScoped;
+
+import dev.langchain4j.store.memory.chat.ChatMemoryStore;
+import dev.langchain4j.store.memory.chat.InMemoryChatMemoryStore;
+
+public class ChatMemoryStoreProducer {
+
+    @ApplicationScoped
+    ChatMemoryStore produceChatMemoryStore() {
+        return new InMemoryChatMemoryStore();
+    }
+}

docs/modules/ROOT/examples/io/quarkiverse/langchain4j/samples/MySmallMemoryProvider.java

@@ -1,32 +1,24 @@
 package io.quarkiverse.langchain4j.samples;
 
-import java.util.Map;
-import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Supplier;
 
-import dev.langchain4j.memory.ChatMemory;
+import jakarta.inject.Inject;
+
 import dev.langchain4j.memory.chat.ChatMemoryProvider;
 import dev.langchain4j.memory.chat.MessageWindowChatMemory;
-import io.quarkiverse.langchain4j.RemovableChatMemoryProvider;
+import dev.langchain4j.store.memory.chat.ChatMemoryStore;
 
 public class MySmallMemoryProvider implements Supplier<ChatMemoryProvider> {
-    @Override
-    public ChatMemoryProvider get() {
-        return new RemovableChatMemoryProvider() {
-            private final Map<Object, ChatMemory> memories = new ConcurrentHashMap<>();
 
-            @Override
-            public ChatMemory get(Object memoryId) {
-                return memories.computeIfAbsent(memoryId, id -> MessageWindowChatMemory.builder()
-                        .maxMessages(20)
-                        .id(memoryId)
-                        .build());
-            }
+    @Inject
+    ChatMemoryStore store;
 
-            @Override
-            public void remove(Object id) {
-                memories.remove(id);
-            }
-        };
+    @Override
+    public ChatMemoryProvider get() {
+        return memoryId -> MessageWindowChatMemory.builder()
+                .id(memoryId)
+                .maxMessages(20)
+                .chatMemoryStore(store)
+                .build();
     }
 }

docs/modules/ROOT/pages/ai-services.adoc

@@ -181,10 +181,18 @@ An example of such a bean is:
 
 [source,java]
 ----
-include::{examples-dir}/io/quarkiverse/langchain4j/samples/ChatMemoryBean.java[]
+include::{examples-dir}/io/quarkiverse/langchain4j/samples/ChatMemoryProviderBean.java[]
 ----
 
-Notice that the messages are deleted when the scope terminates (as it will call the `close` method).
+Additionally, it is important to configure a `ChatMemoryStore` which is responsible for actually storing the chat memory.
+The following example shows how an application wide `InMemoryChatMemoryStore` can be used for this.
+
+[source,java]
+----
+include::{examples-dir}/io/quarkiverse/langchain4j/samples/ChatMemoryStoreProducer.java[]
+----
+
+Notice that with this example, conversations are not deleted and thus accumulate over time.
 
 NOTE: It is recommended to have your chat memory beans implement `RemovableChatMemoryProvider` because the objects used as memory IDs are removed from the memory when the service goes out of scope.