Cache

Overview

Module

• package: org.eclipse.dirigible.sdk.cache
• source: cache/Cache.java

Process-wide key/value cache shared across all client code in the tenant. Backed by the Dirigible platform's in-memory cache manager — values survive the request that wrote them but not a JVM restart, so treat the cache as derived state, not a system of record.

Useful for memoising expensive lookups, holding short-lived per-user state across requests, and coordinating between components that share the same key. Values are stored as plain Objects; the caller is responsible for cast safety.

Key Features

• In-memory: Reads and writes are cheap; data is lost on JVM restart.
• Tenant-wide: A single shared keyspace across all code in the tenant — use prefixed keys (e.g. "user:" + id + ":permissions") to avoid collisions.
• Untyped values: Stores arbitrary Objects; cast on read.
• Polyglot-friendly: Entries are accessible from any language running in the platform, provided the value is JSON-encodable.

Example Usage

import org.eclipse.dirigible.sdk.cache.Cache;

String key = "user:" + userId + ":permissions";
if (!Cache.contains(key)) {
    Cache.set(key, loadPermissions(userId));
}
@SuppressWarnings("unchecked")
Set<String> perms = (Set<String>) Cache.get(key);

Methods

contains()

Reports whether the cache currently holds a value for the given key.

public static boolean contains(String key);

Parameter	Type	Description
key	String	The cache key.

Returns

• Type: boolean
• Description: true if a value is currently cached under key, false otherwise.

get()

Retrieves the cached value for the given key, or null if none.

public static Object get(String key);

Parameter	Type	Description
key	String	The cache key.

Returns

• Type: Object
• Description: The cached value, or null if no value is cached under key. The caller is responsible for cast safety.

set()

Stores a value in the cache under the given key, overwriting any previous value.

public static void set(String key, Object content);

Parameter	Type	Description
key	String	The cache key.
content	Object	The value to cache.

Returns

• Type: void

delete()

Removes the cached entry for the given key. No-op if no value is cached under that key.

public static void delete(String key);

Parameter	Type	Description
key	String	The cache key to remove.

Returns

• Type: void

clear()

Removes every entry from the cache. Use with caution — the cache is shared across all client code in the tenant.

public static void clear();

Returns

• Type: void