Spring - AnnotationBeanNameGenerator Bean命名规则

Posted 2023-01-22 小小工匠

文章目录

• org.springframework.context.annotation.AnnotationBeanNameGenerator

org.springframework.context.annotation.AnnotationBeanNameGenerator

public String generateBeanName(BeanDefinition definition, BeanDefinitionRegistry registry) 
		if (definition instanceof AnnotatedBeanDefinition) 
			String beanName = determineBeanNameFromAnnotation((AnnotatedBeanDefinition) definition);
			if (StringUtils.hasText(beanName)) 
				// Explicit bean name found.
				return beanName;
			
		
		// Fallback: generate a unique default bean name.
		return buildDefaultBeanName(definition);
	

	/**
	 * Derive a default bean name from the given bean definition.
	 * <p>The default implementation simply builds a decapitalized version
	 * of the short class name: e.g. "mypackage.MyJdbcDao" -> "myJdbcDao".
	 * <p>Note that inner classes will thus have names of the form
	 * "outerClassName.innerClassName", which because of the period in the
	 * name may be an issue if you are autowiring by name.
	 * @param definition the bean definition to build a bean name for
	 * @return the default bean name (never <code>null</code>)
	 */
	protected String buildDefaultBeanName(BeanDefinition definition) 
		String shortClassName = ClassUtils.getShortName(definition.getBeanClassName());
		return Introspector.decapitalize(shortClassName);
	

    /**
     * Utility method to take a string and convert it to normal Java variable
     * name capitalization.  This normally means converting the first
     * character from upper case to lower case, but in the (unusual) special
     * case when there is more than one character and both the first and
     * second characters are upper case, we leave it alone.
     * <p>
     * Thus "FooBah" becomes "fooBah" and "X" becomes "x", but "URL" stays
     * as "URL".
     *
     * @param  name The string to be decapitalized.
     * @return  The decapitalized version of the string.
     */
    public static String decapitalize(String name) 
        if (name == null || name.length() == 0) 
            return name;
        
        if (name.length() > 1 && Character.isUpperCase(name.charAt(1)) &&
                        Character.isUpperCase(name.charAt(0)))
            return name;
        
        char chars[] = name.toCharArray();
        chars[0] = Character.toLowerCase(chars[0]);
        return new String(chars);