将 spring 框架 6.0.14 升级到 6.1.6 后，此拼写表达式出现错误

Question

这是咒语表达式：

@Cacheable(value = "Cache", 
    key = "(#request).getToken().hashCode()", 
    unless = "#result == null")

错误：org.springframework.expression.spel.SpelEvaluationException：EL1011E：方法调用：尝试在空上下文对象上调用方法 getAuthenticationRequest()

如何解决这个问题？

Answer 1

我认为答案就在 Javadocs 中：

/**
 * Spring Expression Language (SpEL) expression for computing the key dynamically.
 * <p>Default is {@code ""}, meaning all method parameters are considered as a key,
 * unless a custom {@link #keyGenerator} has been configured.
 * <p>The SpEL expression evaluates against a dedicated context that provides the
 * following meta-data:
 * <ul>
 * <li>{@code #root.method}, {@code #root.target}, and {@code #root.caches} for
 * references to the {@link java.lang.reflect.Method method}, target object, and
 * affected cache(s) respectively.</li>
 * <li>Shortcuts for the method name ({@code #root.methodName}) and target class
 * ({@code #root.targetClass}) are also available.
 * <li>Method arguments can be accessed by index. For instance the second argument
 * can be accessed via {@code #root.args[1]}, {@code #p1} or {@code #a1}. Arguments
 * can also be accessed by name if that information is available.</li>
 * </ul>
 */
String key() default "";

我假设你的

request

是一个参数名称。显然，您的情况无法获得此类信息。尝试使用

-parameters

选项编译您的项目。