Ｊａｖａ反射读取注解时有时无的情况

[tb_bin]

ｊａｖａ反射中，ｍｅｔｈｏｄ．getParameterAnnotations　有时候可以正常读取到注解数组，　但是多数情况读取不到注解数组是什么情况　？　有入坑的伙伴没　？　

public class MethodDemo {
	public static void main(String[] args){
		Method[] methods = SampleClass.class.getMethods();
		Annotation[][] annotations = methods[1].getParameterAnnotations();
		for (Annotation[] annotation1 : annotations) {
			for (Annotation annotation : annotation1) {
				if (annotation instanceof CustomAnnotation) {
					CustomAnnotation customAnnotation = (CustomAnnotation) annotation;
					System.out.println("name: " + customAnnotation.name());
					System.out.println("value: " + customAnnotation.value());
				}
			}
		}
	}
}

@CustomAnnotation(name = "SampleClass", value = "Sample Class Annotation")
class SampleClass {
	private String sampleField;

	public String getSampleField() {
		return sampleField;
	}

	public void setSampleField(
			@CustomAnnotation(name = "sampleClassMethod", value = "Sample Method Annotation") String sampleField) {
		this.sampleField = sampleField;
	}
}

@Retention(RetentionPolicy.RUNTIME)
@interface CustomAnnotation {
	public String name();

	public String value();
}

比如上述代码，有时候可以正常打印出结果：
　　name: sampleClassMethod
　　value: Sample Method Annotation
有时候就读取不到　．　

[tb_bin]

没人入坑吗　？　

[maradona1984]

或许你该打印下methods[1]到底是哪个方法