The use case for 'java memcached delete' is when you want to remove an item (key-value pair) from the Memcached system using Java. This is often done during cache invalidation, where stale or no longer needed data is removed, thus freeing up space for new data.
You can interact with Memcached in Java using libraries like XMemcached or spymemcached. These libraries allow you to perform operations like setting, getting, and deleting keys.
Here's an example using XMemcached:
import net.rubyeye.xmemcached.MemcachedClient; import net.rubyeye.xmemcached.XMemcachedClientBuilder; public class DeleteExample { public static void main(String[] args) { try { // Create a Memcached client MemcachedClient client = new XMemcachedClientBuilder("localhost:11211").build(); // Set a key-value pair client.set("testKey", 3600, "Hello, Memcached"); // Delete the key client.delete("testKey"); } catch (Exception e) { e.printStackTrace(); } } }
This piece of code first connects to a Memcached server running on localhost at port 11211. It then sets a key-value pair ("testKey", "Hello, Memcached"
), with an expiry time of 3600 seconds. Finally, it deletes the key testKey
from the cache.
delete
method will return false
if the key doesn't exist, so you should check this return value.Q: What happens if I try to delete a non-existing key?
A: If you attempt to delete a key which doesn't exist in cache, the delete
method will return false
.
Q: Does Memcached provide any mechanism to delete all keys?
A: Memcached itself does not provide a direct way to delete all keys at once. However, you can use the flush_all
command, but be careful as it invalidates all items in all slabs immediately.
Dragonfly is fully compatible with the Redis ecosystem and requires no code changes to implement.