Annotation to validate required bean attributes [SPR-1047] #5754
Description
Magnus Heino opened SPR-1047 and commented
Bean definitions are required to provide a value for bean attributes defined as required using jdk1.5 annotation.
This provides a check to validate that values are not "forgotten" when creating new bean definitions. Values that are not properly set in the bean definition and are not be used immediately after bean instantiation will not be found otherwise.
package se.lantmateriet.jollen.bryggan.support;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
- JDK 1.5+ method-level annotation that indicates that the value
- is required to be non-null.
@authorMagnus Heino
*/
@Target(ElementType.FIELD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public@interfaceRequiredAttribute {
}
/**
*
*/
package se.lantmateriet.jollen.bryggan.support;
import java.lang.reflect.Field;
import org.springframework.beans.BeansException;
import org.springframework.beans.MutablePropertyValues;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.support.BeanDefinitionValidationException;
/**
@authormaghei
*/
public class RequiredAttributeValidator implements BeanFactoryPostProcessor {
/* (non-Javadoc)
* @see org.springframework.beans.factory.config.BeanFactoryPostProcessor#postProcessBeanFactory(org.springframework.beans.factory.config.ConfigurableListableBeanFactory)
*/
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
for(String beanName: beanFactory.getBeanDefinitionNames()) {
BeanDefinition beanDefinition = beanFactory.getBeanDefinition(beanName);
if(beanDefinition.isAbstract()) {
continue;
}
MutablePropertyValues beanProperties = beanDefinition.getPropertyValues();
for(Field field: beanFactory.getType(beanName).getDeclaredFields()) {
RequiredAttribute requiredAttribute = field.getAnnotation(RequiredAttribute.class);
if(requiredAttribute != null) {
Object value = beanProperties.getPropertyValue(field.getName());
if(value == null) {
throw new BeanDefinitionValidationException("Required attribute '" + field.getName() + "' of class '" + beanDefinition.getClass().getName() + "' defined in bean '" + beanName + "' in file '" + beanDefinition.getResourceDescription() + "' is null.");
}
}
}
}
}
}
Attachments:
- RequiredPropertyValidator.java (9.67 kB)
- RequiredPropertyValidator.java (8.82 kB)
Issue Links:
- Annotations for dependency checking [SPR-1419] #6119 Annotations for dependency checking ("is duplicated by")