There was an unexpected error (type=Bad Request, status=400). Required Long parameter 'isPay' is not

忘是亡心i 2022-02-28 02:36 1186阅读 0赞

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## 异常信息 ##

Whitelabel Error Page
    This application has no explicit mapping for /error, so you are seeing this as a fallback.
    Sun Mar 24 10:42:00 CST 2019
    There was an unexpected error (type=Bad Request, status=400).
    Required Long parameter 'isPay' is not present

--------------------

## 场景描述 ##

package com.ysy.service.impl;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.RequestParam;
    import org.springframework.web.bind.annotation.RestController;
    
    import com.ysy.api.order.OrderService;
    import com.ysy.base.BaseApiService;
    import com.ysy.base.ResponseBase;
    import com.ysy.dao.OrderDao;
    
    @RestController
    public class OrderServiceImpl extends BaseApiService implements OrderService {
    	@Autowired
    	private OrderDao orderDao;
    
    	@Override
    	public ResponseBase updateOrder(@RequestParam("isPay") Long isPay, @RequestParam("payId") String aliPayId,
    			@RequestParam("orderNumber") String orderNumber) {
    		int updateOrder = orderDao.updateOrder(isPay, aliPayId, orderNumber);
    		if (updateOrder <= 0) {
    			return setReasultError("系统错误!");
    		}
    		return setReasultSuccess();
    	}
    
    }

--------------------

## 异常原因 ##

一旦我们在方法中定义了@RequestParam变量，如果访问的URL中不带有相应的参数，就会抛出异常——这是显然的，Spring尝试帮我们进行绑定，然而没有成功。但有的时候，参数确实不一定永远都存在，这是我们可以通过定义required属性：

@RequestParam(name="id",required=false)
    //在参数不存在的情况下，可能希望变量有一个默认值
    @RequestParam(name="id",required=false,defaultValue="0")

--------------------

## 解决方案 ##

package com.ysy.service.impl;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.RequestParam;
    import org.springframework.web.bind.annotation.RestController;
    
    import com.ysy.api.order.OrderService;
    import com.ysy.base.BaseApiService;
    import com.ysy.base.ResponseBase;
    import com.ysy.dao.OrderDao;
    
    @RestController
    public class OrderServiceImpl extends BaseApiService implements OrderService {
    	@Autowired
    	private OrderDao orderDao;
    
    	@Override
    	public ResponseBase updateOrder(@RequestParam(value = "payState", required = false) Long payState,
    			@RequestParam(value = "payId", required = false) String payId,
    			@RequestParam(value = "orderNumber", required = false) String orderNumber) {
    		int updateOrder = orderDao.updateOrder(payState, payId, orderNumber);
    		if (updateOrder <= 0) {
    			return setReasultError("系统错误!");
    		}
    		return setReasultSuccess();
    	}
    
    }

--------------------

## 参考资料 ##

![在这里插入图片描述][20190324110723254.png]

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[20190324110723254.png]: /images/20220228/eda3928b161e4d97a0457825a8e81e6d.png