java - 在响应实体方法中拆分字符串数组导致参数不存在错误

Question

我有一个 Spring Boot 应用程序，能够处理 HTTP POST 请求。 我有一个 ResponseEntity，它接受字符串参数，并在您向服务器发送 POST 请求时生成 JSON 输出。我希望输入负载为 18 个参数。

例如:

curl -d "ncp|56-2629193|1955-11-28|20190103|73630|6404|182232|self|-123|-123|-123|0.0|0.0|0.0|0.0|0.0" http://localhost:9119/payload 

将返回此 json:

{"status": true, "HasDeductible": {"probability": "0.1871", "value": "N"}, "CoinsurancePercent": {"value": 0}, "AllowableAmount": {"value": 414.55}, "PatientRespon": {"probability": "0.1055", "value": "N"}, "coreName": "Patient_Responsibility", "DeductibleAmount": {"value": 0}, "version": "0.97", "HasCoinsurance": {"probability": "0.0722", "value": "N"}, "CopayAmount": {"value": 0}, "HasCopay": {"probability": "0.0479", "value": "N"}, "CoinsuranceAmount": {"value": 0}}

我在资源文件夹的文本文件中包含此 JSON，我从端点调用该文件到 Controller 。我做了一个正则表达式拆分，将其放入字符串数组中，以便能够将其分成参数并接受 18。

这是我的 Controller 类

import java.io.IOException;
import java.util.Map;

import javax.validation.constraints.NotNull;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@Validated
@RestController
public class MockController {

    @Autowired
    MockEndPoint mockendpoint;

    @RequestMapping(value = "/", method = RequestMethod.GET)
    public String index() {
        return "hello!";
    }

    @RequestMapping(value = "/payload", method = RequestMethod.POST, produces = {"application/json"})
    public ResponseEntity<String> payloader1(@RequestParam String params ) throws IOException{
        String type = mockendpoint.Payload1();
        String[] a = params.split("\\|");
        if (a.length == 18) 
        {
        return ResponseEntity.ok(type); 
        }
        else {
            return ResponseEntity.status(HttpStatus.BAD_REQUEST).body("Inccorect payload amount");
        }



    }
}

这是我的端点类

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.util.ResourceUtils;

@Configuration
public class MockEndPoint {

    @Bean
    public String Payload1() throws IOException {
        File file = ResourceUtils.getFile("src/test/resources/Payload1.txt");
        String content = new String(Files.readAllBytes(file.toPath()));
        return content;
    }
}

当我尝试curl命令时，它给了我这个错误:

{"timestamp":"2019-07-24T16:55:35.589+0000","status":400,"error":"Bad Request","message":"Required String parameter 'params' is not present","path":"/payload"}

编辑:看来我的行中有一个 NullPointerException

String[] a = params.split("\\|");

如果我正确地考虑这一点，params 从技术上讲是空的。我该如何克服这个问题？

Answer 1

您看到的错误反射(reflect)您的应用程序未接受请求，它甚至还没有读取您的文件。

您的 /payload 端点需要一个名为 params 的请求参数，但您没有提供该参数。相反，您将发布请求正文。要实现此功能，您需要将 @RequestParam 替换为 @RequestBody 注释。您的 payloader1 方法签名将如下所示

@RequestMapping(value = "/payload", method = RequestMethod.POST, produces = {"application/json"})
    public ResponseEntity<String> payloader1(@RequestBody String params) throws IOException {
}

进行更改并发送您的 curl 请求后，我得到

$ curl -d "ncp|56-2629193|1955-11-28|20190103|73630|6404|182232|self|-123|-123|-123|0.0|0.0|0.0|0.0|0.0" 'http://localhost:9119/payload'
Inccorect payload amount

如果我将正文更改为包含 18 个管道分隔值，我会得到

$ curl -d "ncp|56-2629193|1955-11-28|20190103|73630|6404|182232|self|-123|-123|-123|0.0|0.0|0.0|0.0|0.0|0.0|0.0" -H 'Content-Type: text/plain' 'http://localhost:9119/payload'
{"status": true, "HasDeductible": {"probability": "0.1871", "value": "N"}, "CoinsurancePercent": {"value": 0}, "AllowableAmount": {"value": 414.55}, "PatientRespon": {"probability": "0.1055", "value": "N"}, "coreName": "Patient_Responsibility", "DeductibleAmount": {"value": 0}, "version": "0.97", "HasCoinsurance": {"probability": "0.0722", "value": "N"}, "CopayAmount": {"value": 0}, "HasCopay": {"probability": "0.0479", "value": "N"}, "CoinsuranceAmount": {"value": 0}}