Spring中的@ControllerAdvice三种用法详解

//匹配org.my.pkg包及其子包下的所有Controller
@ControllerAdvice(basePackages="org.my.pkg")
//当然也可以用数组的形式指定，如：
@ControllerAdvice(basePackages={"org.my.pkg", "org.my.other.pkg"}),

@ControllerAdvice（annotations={CustomAnnotation.class})

// 1.无返回值方法,放入Model,自定义 key ,value
    @ModelAttribute()
    public void presetParam(Model model) {
        model.addAttribute("globalAttr", "我是全局参数");
    }
    // 2.不有指定name,返回值方法,返回值是map,int等,key就是map,int等,,value是返回值
    @ModelAttribute()
    public Map<String, String> presetParam2() {
        Map<String, String> map1 = new HashMap<String, String>();
        map1.put("key1", "value1");
        return map1;
    }
    // 3.指定name,返回值方法,key就是name,value是返回值
    @ModelAttribute(name = "map2")
    public Map<String, String> presetParam3() {
        Map<String, String> map = new HashMap<String, String>();
        map.put("key2", "value2");
        return map;
    }
	// 4.可以接受请求参数
    @ModelAttribute()
    public void presetParam4(@RequestParam("name") String name,Model model) {
        model.addAttribute("name", name);
    }

 //1.使用Model取出
    @GetMapping("model")
    public String methodOne(Model model) {
        Map<String, Object> modelMap = model.asMap();
        System.out.println(modelMap.get("name").toString()); // 传入name的值    
        return modelMap.get("globalAttr").toString();
    }
    //2.使用ModelMap取出
    @GetMapping("modelMap")
    public String methodThree(ModelMap modelMap) {
        return modelMap.get("map").toString();
    }
    //3.@ModelAttribute()指定key,直接取出
    @GetMapping("modelAttribute")
    public String methodTwo(@ModelAttribute("map2") Map map2) {
        return map2.toString();
    }

// @Validated参数校验 ,解析BindingResult的错误信息并返回
    @ExceptionHandler(BindException.class)
    @ResponseBody
    public JsonResult exceptionHandler(BindException e, BindingResult result) {
        List<FieldError> fieldErrors = result.getFieldErrors();
        String collect = fieldErrors.stream().map(f -> f.getField()+":"+f.getDefaultMessage()).collect(Collectors.joining(","));
        return new JsonResult(JsonResult.Validated_ERROR, collect);
    }
	//这里就是通用的异常处理器了,所有预料之外的Exception异常都由这里处理
    @ExceptionHandler(Exception.class)
    @ResponseBody
    public JsonResult exceptionHandler(Exception e) {
        return new JsonResult(JsonResult.SYSTEM_ERROR, e.getMessage());
    }

 @InitBinder
    public void initBinder(WebDataBinder dataBinder){
        /*
         * 创建一个字符串微调编辑器
         * 参数{boolean emptyAsNull}: 是否把空字符串("")视为 null
         */
        StringTrimmerEditor trimmerEditor = new StringTrimmerEditor(true);
        /*
         * 注册自定义编辑器
         * 接受两个参数{Class<?> requiredType, PropertyEditor propertyEditor}
         * requiredType：所需处理的类型
         * propertyEditor：属性编辑器，StringTrimmerEditor就是 propertyEditor的一个子类
         */
        dataBinder.registerCustomEditor(String.class, trimmerEditor);
        //日期格式的字符串转换成Date对象
       dataBinder.registerCustomEditor(Date.class, new CustomDateEditor(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"), false));
        
   dataBinder.addValidators(paramVOValidator);

}

 /**
    * @description:  防止xss注入
    * @params:  String类型转换，将所有传递进来的String进行HTML编码，防止XSS攻击
    * @return:
    */
    //@InitBinder
    protected void initBinder2(WebDataBinder binder) {
        System.out.println("22222222222222");
       //自定义属性编辑器 PropertyEditorSupport
        binder.registerCustomEditor(String.class, new PropertyEditorSupport() {
            @Override
            public void setAsText(String text) {
                setValue(text == null ? null : StringEscapeUtils.escapeHtml4(text.trim()));
            }
            @Override
            public String getAsText() {
                Object value = getValue();
                return value != null ? value.toString() : "";
            }
        });
    }

@Data
public class ParamVO implements Serializable {

    @ApiModelProperty("age")
    private Integer age;
    
    @ApiModelProperty("name")
    private String name;
}

@Component
public class ParamVOValidator implements Validator {

	/**
	* @description:  满足条件才往下走
	* @params:
	* @return:
	*/
    @Override
    public boolean supports(Class<?> clazz) {
        // 只支持ParamVO类型对象的校验
        return ParamVO.class.equals(clazz);
    }

    /**
    * @description:  自定义校验规则
    * @params:
    * @return:
    */
    @Override
    public void validate(Object target, Errors errors) {
        ParamVO paramVO = (ParamVO) target;
        String userName = paramVO.getName();
        if (StringUtils.isEmpty(userName) || userName.length() < 8) {
            errors.rejectValue("name", "valid.userNameLen", new Object[]{"minLength", 8}, "用户名不能少于8位");
        }

    }
}

	@Autowired
    private ParamVOValidator paramVOValidator;
     @InitBinder
    public void initBinder(WebDataBinder dataBinder) {
        dataBinder.addValidators(paramVOValidator);
    
    }