fix:make sure attribute exists

[jcsxky]

What is the purpose of the change

make sure attribute exists

Brief changelog

when dubug or call toString method of AbstractConfig,the field may not exist.For example, when getClass refer to ReferenceBean,it will call getObject() and init method in ReferenceConfig,when it is not initialized,interfaceName is null and throws an Exception, but initialized set to be true.this will lead to service bean cannot be created successfully.

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[Leishunyu]

Can you fix the ci And is the log output more detailed?

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[chickenlj]

Thanks. Merged manually to avoid conflicts.

[kylixs]

Some attribute does not has a corresponding field, but has a pair of getter/setter methods, e.g. String getInterface()/setInterface(String) of ReferenceConfig.
So it’s better to check if the attribute is writable, see aslo: #8289

    protected List<Method> computeAttributedMethods() {
        Class<? extends AbstractConfig> cls = this.getClass();
        BeanInfo beanInfo = getBeanInfo(cls);
        List<Method> methods = new ArrayList<>(beanInfo.getMethodDescriptors().length);
        for (MethodDescriptor methodDescriptor : beanInfo.getMethodDescriptors()) {
            Method method = methodDescriptor.getMethod();
            if (MethodUtils.isGetter(method)) {
                // filter non attribute
                Parameter parameter = method.getAnnotation(Parameter.class);
                if (parameter != null && !parameter.attribute()) {
                    continue;
                }
                String propertyName = calculateAttributeFromGetter(method.getName());
                // filter non writable property, exclude non property methods, fix #4225
                if (!isWritableProperty(beanInfo, propertyName)) {
                    continue;
                }
                methods.add(method);
            }
        }
        return methods;
    }