java - 带有动态参数的自定义注释

Question

这是我的问题:

我有一个注释:

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface DummyAnnotation {
String dummyParam1();
String dummyParam2();
}

我的服务是:

@Component
public class DummyService {

@DummyAnnotation(dummyParam1="#otp",dummyParam2="#transactionId")
public void dummy(String otp, String transactionId){

}
}

我的方面正在尝试验证两个参数，如果验证不成功则抛出异常:

 @Around(value = "@annotation(annotation)")
public Object verifyOtp(final ProceedingJoinPoint jointPoint, final DummyAnnotation  annotation) throws Throwable {
            String transactionId = annotation.dummyParam1();
            String otp = annotation.dummyParam2();
            Boolean otpValid = otpService.verify(transactionId, otp);
            if (otpValid) {
                return jointPoint.proceed();
            }
            else {
                throw new AuthentificationForteException();
            }

}

我怎样才能让它工作，因为 Spring EL 不工作，而在我的方面我有dummyAnnotation.dummyParam1() 等于“#otp”，而不是我的参数 String otp 的值。

提前致谢。

Answer 1

最后我找到了解决方案:

解决方案是实现一个特定的 Spring 表达式解析器。
我将这些声明添加到我的方面:

private ExpressionParser expressionParser = new SpelExpressionParser();
private ParserContext parserContext = new TemplateParserContext();

我改变了检索虚拟值的方式:

@Around(value = "@annotation(annotation)")
public Object verifyOtp(final ProceedingJoinPoint jointPoint, final DummyAnnotation  annotation) throws Throwable {

String transactionId = getDummyValue(annotation.dummyParam1(),jointPoint.getArgs());
String otp = getDummyValue(annotation.dummyParam2(),jointPoint.getArgs());

        Boolean otpValid = otpService.verify(transactionId, otp);
        if (otpValid) {
            return jointPoint.proceed();
        }
        else {
            throw new AuthentificationForteException();
        }

}

getDummyValue 是解析表达式的方法:

private String getDummyValue(String authExpression,  Object[] args){
    Expression expression = expressionParser.parseExpression(authExpression, parserContext);
    String value = expression.getValue(new RootObject(args),String.class);
    return value;
}


private static class TemplateparserContext implements ParserContext{

    @Override
    public boolean isTemplate() {
        return true;
    }

    @Override
    public String getExpressionPrefix() {
        return "#{";
    }

    @Override
    public String getExpressionSuffix() {
        return "}";
    }

}

 protected static class RootObject {

        private final Object[] args;

        private RootObject(Object[] args) {
            super();
            this.args = args;
        }

        public Object[] getArgs() {
            return args;
        }
    }

最后我将我的服务和 DummyAnnotation 的使用更改为:

 @Component
 public class DummyService {

 @DummyAnnotation(dummyParam1="#{args[0]}",dummyParam2="#{args[1]}")
 public void dummy(String otp, String transactionId){

 }
 }