Interface RemovalListener<K,V>

Type Parameters:
K - the type of keys | 键类型
V - the type of values | 值类型
Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
@FunctionalInterface public interface RemovalListener<K,V>
Removal Listener SPI - Cache entry removal callback interface 移除监听器 SPI - 缓存条目移除回调接口

Provides callback when cache entries are removed for any reason.

当缓存条目因任何原因被移除时提供回调。

Features | 主要功能:

  • Notification on entry removal - 条目移除时通知
  • Access to removal cause - 访问移除原因
  • Logging and auditing - 日志和审计

Usage Examples | 使用示例:

RemovalListener<String, User> listener = (key, value, cause) -> {
    if (cause.wasEvicted()) {
        log.info("User cache evicted: {}", key);
    }
};

Security | 安全性:

  • Thread-safe: Implementation dependent - 线程安全: 取决于实现
  • Null-safe: value may be null - 空值安全: value 可能为 null
Since:
JDK 25, opencode-base-cache V1.0.0
Author:
Leon Soo www.LeonSoo.com
See Also:

  • Method Summary

    Modifier and Type
    Method
    Description
    static <K,V> RemovalListener<K,V>
    combine(RemovalListener<K,V>... listeners)
    Combine multiple listeners 组合多个监听器
    static <K,V> RemovalListener<K,V>
    logging()
    Create a listener that logs removals 创建一个记录移除日志的监听器
    static <K,V> RemovalListener<K,V>
    noOp()
    Create a listener that does nothing 创建一个什么都不做的监听器
    void
    onRemoval(K key, V value, RemovalCause cause)
    Called when an entry is removed from cache 当条目从缓存中移除时调用

  • Method Details

    • onRemoval

      void onRemoval(K key, V value, RemovalCause cause)
      Called when an entry is removed from cache 当条目从缓存中移除时调用
      Parameters:
      key - the key being removed | 被移除的键
      value - the value being removed (may be null) | 被移除的值（可能为 null）
      cause - the removal cause | 移除原因

    • noOp

      static <K,V> RemovalListener<K,V> noOp()
      Create a listener that does nothing 创建一个什么都不做的监听器
      Type Parameters:
      K - key type | 键类型
      V - value type | 值类型
      Returns:
      no-op listener | 空操作监听器

    • logging

      static <K,V> RemovalListener<K,V> logging()
      Create a listener that logs removals 创建一个记录移除日志的监听器
      Type Parameters:
      K - key type | 键类型
      V - value type | 值类型
      Returns:
      logging listener | 日志监听器

    • combine

      @SafeVarargs static <K,V> RemovalListener<K,V> combine(RemovalListener<K,V>... listeners)
      Combine multiple listeners 组合多个监听器
      Type Parameters:
      K - key type | 键类型
      V - value type | 值类型
      Parameters:
      listeners - the listeners | 监听器列表
      Returns:
      combined listener | 组合后的监听器