The Basics

NamedMap and NamedCache are dict-like structures allowing users to store data within a remote Coherence cluster.

The following is an example of using a NamedMap to store, get, and remove simple keys and values:

 1# Copyright (c) 2023, Oracle and/or its affiliates.
 2# Licensed under the Universal Permissive License v 1.0 as shown at
 3# https://oss.oracle.com/licenses/upl.
 4
 5import asyncio
 6
 7from coherence import NamedMap, Session
 8
 9
10async def do_run() -> None:
11    """
12    Demonstrates basic CRUD operations against a NamedMap using
13    `int` keys and `str` values.
14
15    :return: None
16    """
17    session: Session = await Session.create()
18    try:
19        named_map: NamedMap[int, str] = await session.get_map("my-map")
20
21        print("Put key 1; value one")
22        await named_map.put(1, "one")
23
24        print("Value for key 1 is :", await named_map.get(1))
25
26        print("NamedMap size is :", await named_map.size())
27
28        print("Updating value of key 1 to ONE from ", await named_map.put(1, "ONE"))
29
30        print("Value for key 1 is :", await named_map.get(1))
31
32        print("Removing key 1, current value :", await named_map.remove(1))
33
34        print("NamedMap size is :", await named_map.size())
35    finally:
36        await session.close()
37
38
39asyncio.run(do_run())
  • Line 17 - Create a new Session that will connect to localhost:1408. See the Sessions documentation for more details.

  • Line 50 - Obtain a NamedMap identified by my-map from the Session

  • Lines 21-34 - Various CRUD operations against the NamedMap such as get(), put(), and remove()