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InMemoryConversationHistoryStore

This docs was updated at: 2026-02-23

com.paragon.messaging.store.history.InMemoryConversationHistoryStore  ยท  Class

Implements ConversationHistoryStore

In-memory implementation of ConversationHistoryStore.

Stores conversation history in memory with configurable per-user limits and LRU eviction. Suitable for development, testing, and single-instance deployments where persistence across restarts is not required.

Features

  • Thread-safe with fine-grained locking per user
  • LRU eviction when per-user limit is reached
  • Timestamped messages for age-based filtering
  • Automatic cleanup of expired messages

Usage Example

// Create with default settings (100 messages per user)
ConversationHistoryStore store = InMemoryConversationHistoryStore.create();
// Create with custom per-user limit
ConversationHistoryStore store = InMemoryConversationHistoryStore.create(50);
// Create with builder for full customization
ConversationHistoryStore store = InMemoryConversationHistoryStore.builder()
    .maxMessagesPerUser(200)
    .build();

Thread Safety

This implementation is thread-safe. Operations on different users can proceed concurrently. Operations on the same user are serialized using per-user read-write locks for optimal concurrent read performance.

See Also

  • ConversationHistoryStore

Since: 2.1

Methods

create

public static InMemoryConversationHistoryStore create()

Creates a new store with default settings (100 messages per user).

Returns

a new InMemoryConversationHistoryStore

create

public static InMemoryConversationHistoryStore create(int maxMessagesPerUser)

Creates a new store with the specified per-user message limit.

Parameters

Name Description
maxMessagesPerUser maximum messages to store per user

Returns

a new InMemoryConversationHistoryStore

builder

public static Builder builder()

Creates a builder for customizing the store.

Returns

a new builder

getUserCount

public int getUserCount()

Returns the current number of users with stored history.

Returns

the number of users

getMaxMessagesPerUser

public int getMaxMessagesPerUser()

Returns the maximum messages stored per user.

Returns

the per-user limit

maxMessagesPerUser

public Builder maxMessagesPerUser(int max)

Sets the maximum number of messages to store per user.

When this limit is reached, older messages are evicted (LRU).

Parameters

Name Description
max the maximum messages per user

Returns

this builder

build

public InMemoryConversationHistoryStore build()

Builds the configured InMemoryConversationHistoryStore.

Returns

the store instance