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默认属性编辑器

这段代码的意思就设置默认属性编辑器

protected void prepareBeanFactory(ConfigurableListableBeanFactory beanFactory) {
   	...		//设置默认属性编辑器		//registerBeanPostProcessors会注册所有自定义编辑器,对应AbstractBeanFactory.customEditors		//AbstractBeanFactory.initBeanWrapper会使用编辑器,对应AbstractBeanFactory.propertyEditorRegistrars		beanFactory.addPropertyEditorRegistrar(new ResourceEditorRegistrar(this, getEnvironment()));...	}

在初始化BeanWrapper的时候会注册属性编辑器到BeanWrapper中

/*org.springframework.beans.factory.support.AbstractBeanFactory#initBeanWrapper */	protected void initBeanWrapper(BeanWrapper bw) {
   ...		//注册编辑器		registerCustomEditors(bw);	}

protected void registerCustomEditors(PropertyEditorRegistry registry) {
   ...					//批量注册通用属性编辑器						if (registry instanceof PropertyEditorRegistrySupport) {
   			((PropertyEditorRegistrySupport) registry).overrideDefaultEditor(requiredType, editor);		}...		}	}

执行到这里基本就注册到BeanWrapper中overriddenDefaultEditors属性了

public void overrideDefaultEditor(Class
    requiredType, PropertyEditor propertyEditor) {
   		if (this.overriddenDefaultEditors == null) {
   			this.overriddenDefaultEditors = new HashMap<>();		}		this.overriddenDefaultEditors.put(requiredType, propertyEditor);	}

自定义属性编辑器方式一之直接注册

配置文件如下

自定义解析类

public class DatePropertyEditor extends PropertyEditorSupport {
       private String format = "yyyy-MM-dd";    public void setFormat(String format) {
           this.format = format;    }    @Override    public void setAsText(String text) throws IllegalArgumentException {
           SimpleDateFormat simpleDateFormat = new SimpleDateFormat(format);        try {
               Date parse = simpleDateFormat.parse(text);            this.setValue(parse);        } catch (ParseException e) {
               e.printStackTrace();        }    }}

首先可以看到配置文件配置的CustomEditorConfigurer类继承了BeanFactoryPostProcessor接口,这个接口的意思就是生成bean之前首先执行这个接口里面postProcessBeanFactory方法

public class CustomEditorConfigurer implements BeanFactoryPostProcessor, Ordered {
   @Override	public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
   		if (this.propertyEditorRegistrars != null) {
   			for (PropertyEditorRegistrar propertyEditorRegistrar : this.propertyEditorRegistrars) {
   				beanFactory.addPropertyEditorRegistrar(propertyEditorRegistrar);			}		}...	}}

当执行invokeBeanFactoryPostProcessors方法的时候,会查询所有的继承了BeanFactoryPostProcessor接口的postProcessBeanFactory方法

@Override	public void refresh() throws BeansException, IllegalStateException {
   		...				// Invoke factory processors registered as beans in the context.				//激活各种BeanFactory处理器				//BeanFactoryPostProcessor作用域容器级,仅仅对容器中的bean进行后置处理,如propertyPlaceholderConfig,继承order可实现排序调用功能				//BeanFactoryPostProcessor可以修改实际的bean实例				invokeBeanFactoryPostProcessors(beanFactory);***	}

这个时候就会把配置文件配置了customEditors属性的值经过CustomEditorConfigurer类的postProcessBeanFactory方法,注册到BeanFactory的customEditors属性,然后当执行registerCustomEditors的时候注册

/*	注册默认属性编辑器	注册自定义属性编辑器	 */	protected void registerCustomEditors(PropertyEditorRegistry registry) {
   ...		//注册自定义属性编辑器		if (!this.customEditors.isEmpty()) {
   			this.customEditors.forEach((requiredType, editorClass) ->					registry.registerCustomEditor(requiredType, BeanUtils.instantiateClass(editorClass)));		}	}

执行注册方法,注册到customEditors缓存中

@Override	public void registerCustomEditor(@Nullable Class
    requiredType, @Nullable String propertyPath, PropertyEditor propertyEditor) {
   ...			//注册自定义属性编辑器			if (this.customEditors == null) {
   				this.customEditors = new LinkedHashMap<>(16);			}			this.customEditors.put(requiredType, propertyEditor);			this.customEditorCache = null;		...	}

自定义属性编辑器方式二之本地注册

配置文件

这里使用spring提供的解析器

public class DatePropertyEditorRegistry implements PropertyEditorRegistrar {
       public void registerCustomEditors(PropertyEditorRegistry registry) {
           registry.registerCustomEditor(Date.class,                new CustomDateEditor(new SimpleDateFormat("yyyy-MM-dd"), true));    }}

用的还是CustomEditorConfigurer,只不过注入的属性是propertyEditorRegistrars，跟上述一样,执行的方法变了.会加载到BeanFactory的propertyEditorRegistrars属性中

@Override	public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
   		//注册		if (this.propertyEditorRegistrars != null) {
   			for (PropertyEditorRegistrar propertyEditorRegistrar : this.propertyEditorRegistrars) {
   				beanFactory.addPropertyEditorRegistrar(propertyEditorRegistrar);			}		}..	}

在初始化BeanWrapper的时候会执行以下方法

protected void registerCustomEditors(PropertyEditorRegistry registry) {
   ...					//批量注册通用属性编辑器					registrar.registerCustomEditors(registry);...	}

然后调用我们自定义的类进行注册

public class DatePropertyEditorRegistry implements PropertyEditorRegistrar {
       public void registerCustomEditors(PropertyEditorRegistry registry) {
           registry.registerCustomEditor(Date.class,                new CustomDateEditor(new SimpleDateFormat("yyyy-MM-dd"), true));    }}

执行注册方法,注册到customEditors缓存中

@Override	public void registerCustomEditor(@Nullable Class
    requiredType, @Nullable String propertyPath, PropertyEditor propertyEditor) {
   ...			//注册自定义属性编辑器			if (this.customEditors == null) {
   				this.customEditors = new LinkedHashMap<>(16);			}			this.customEditors.put(requiredType, propertyEditor);			this.customEditorCache = null;	...		}

自定义属性编辑器方式三之自定义转换服务类

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