WebService简介

WebService接口的发布通常一般都是使用WSDL（web service descriptive language）文件的样式来发布的，该文档包含了请求的参数信息，返回的结果信息，我们需要根据WSDL文档的信息来编写相关的代码进行调用WebService接口。接下来我将采用常见的两种方式调用WebService接口。

---

场景描述

目前我需要使用java调用C#系统的一个WebService接口，传递参数为一个表号，返回的是一个Xml的数据类型，需要实现调用接口，获取到xml之后并解析为Json格式数据，并返回给前端。Java调用WebService接口，需要根据提供接口方的XSD文档编写相关代码，Xsd文档可以直接通过提供的接口地址进行查看。

---

WebServiceTemplate调用WebService接口实现

1.导入相关的依赖包，如下：

  <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web-services</artifactId>
  </dependency>

2.使用WebServiceTemplate实现调用WebService接口，需要编写先关的解析类，根据提供的XSDL文档编写先关代码，XSDL文档信息如下：

POST /rootServiceFlow/EBoardService.asmx HTTP/1.1
Host: 10.200.0.74
Content-Type: text/xml; charset=utf-8
Content-Length: length
SOAPAction: "http://tempuri.org/AAFlow002x"

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
 <soap:Body>
   <AAFlow002x xmlns="http://tempuri.org/">
     <LotNo>string</LotNo>
   </AAFlow002x>
 </soap:Body>
</soap:Envelope>

上面的信息是包含请求所需要传递的参数，字段为LotNo。接下来XSDL的文档信息为返回的数据格式，如下：

HTTP/1.1 200 OK
Content-Type: text/xml; charset=utf-8
Content-Length: length

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
  <soap:Body>
    <AAFlow002xResponse xmlns="http://tempuri.org/">
      <AAFlow002xResult>string</AAFlow002xResult>
    </AAFlow002xResponse>
  </soap:Body>
</soap:Envelope>

需要根据以上信息编写请求类AAFlow002x，响应接收解析类AAFlow002xResponse，和ObjectFactory类，这三个类可以使用Idea的终端通过命令的方式生成对应的java类，也可以通过自己编写生成java类。通过命令的方式如下：

xjc -d /path/to/output http://example.com/sample.xsd

/path/to/output为生成类的目录，http://example.com/sample.xsd为webServce的接口地址，生成的类如下：

AAFlow002x类编写如下：

import lombok.Data;
import javax.xml.bind.annotation.*;

@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "",  propOrder = {
        "LotNo"
})
@XmlRootElement(name = "AAFlow002x", namespace = "http://tempuri.org/")
@Data
public class AAFlow002x {
    @XmlElement(name = "LotNo", namespace = "http://tempuri.org/", required = true)
    protected String LotNo;
}

AAFlow002xResponse类编写如下：


import lombok.Data;
import javax.xml.bind.annotation.*;

@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "AAFlow002xResponse", namespace = "http://tempuri.org/", propOrder = {
        "AAFlow002xResult"
})
@XmlRootElement(name = "AAFlow002xResponse")
@Data
public class AAFlow002xResponse {
    @XmlElement(name = "AAFlow002xResult", namespace = "http://tempuri.org/", required = true)
    private String AAFlow002xResult;
}

ObjectFatoty类编写如下：

import javax.xml.bind.JAXBElement;
import javax.xml.bind.annotation.XmlElementDecl;
import javax.xml.bind.annotation.XmlRegistry;
import javax.xml.namespace.QName;

@XmlRegistry
public class ObjectFactory {
    private final static QName _AAFlow002_QNAME = new QName("http://tempuri.org/", "AAFlow002x");
    private final static QName _AAFlow002Response_QNAME = new QName("http://tempuri.org/", "AAFlow002xResponse");

    public ObjectFactory() {
    }

    public AAFlow002x createAAFlow002x() {
        return new AAFlow002x();
    }

    public AAFlow002xResponse createAAFlow002xResponse() {
        return new AAFlow002xResponse();
    }

    @XmlElementDecl(namespace = "http://tempuri.org/", name = "AAFlow002x")
    public JAXBElement<AAFlow002x> createAAFlow002x(AAFlow002x value) {
        return new JAXBElement<AAFlow002x>(_AAFlow002_QNAME, AAFlow002x.class, null, value);
    }

    @XmlElementDecl(namespace = "http://tempuri.org/", name = "AAFlow002yResponse")
    public JAXBElement<AAFlow002xResponse> createAAFlow002yResponse(AAFlow002xResponse value) {
        return new JAXBElement<AAFlow002xResponse>(_AAFlow002Response_QNAME, AAFlow002xResponse.class, null, value);
    }
}

编写使用WebServiceTemplate进行调用

@Service
@Slf4j
public class TestWebService {
 
    private static final String ENDPOINT_URL = "这里填写你调用的WebService接口地址";
    private static final String SOAP_ACTION = "http://tempuri.org/AAFlow002x";
    
    public  String  getDataTable(String LotNo) {
         //         创建WebServiceTemplate对象
        WebServiceTemplate webServiceTemplate = new WebServiceTemplate();
        Jaxb2Marshaller marshaller = new Jaxb2Marshaller();
        // 设置解析类，这里填写包的路径为AAFlow002xResponse类所在路径
        marshaller.setContextPath("org.test.parse");
        webServiceTemplate.setMarshaller(marshaller);
        webServiceTemplate.setUnmarshaller(marshaller);
        // 封装请求参数
        AAFlow002x aaFlow002 = new ObjectFactory().createAAFlow002x();
        aaFlow002.setLotNo("22113102");

        // 创建SOAP请求回调对象，这里的SOAP_ACTION指定你调用的接口的哪个方法
        SoapActionCallback soapActionCallback = new SoapActionCallback(SOAP_ACTION);

        // 调用WebService接口，发送请求并返回数据
        JAXBElement<AAFlow002xResponse> aaFlow002xResponse = (JAXBElement<AAFlow002xResponse>) webServiceTemplate.marshalSendAndReceive(ENDPOINT_URL, aaFlow002, soapActionCallback);
        String result = aaFlow002xResponse.getValue().getAAFlow002xResult();
        // 输出响应结果
        System.out.println(aaFlow002xResponse.getValue().getAAFlow002xResult());
        return result;
         }
    }

编写完成之后，Debug启动项目。出现如下图所示证明调用接口成功：

我们可以针对以上代码进行优化，写一个WebServiceConfig类，专门对WebServiceTemplate进行配置，这里就不在赘述。
采用WebServiceTemplate接口调用WebService接口,虽然可以采用命令的方式生成对应的Java代码，但是其缺点是如果请求的参数和返回的参数数据结构很复杂，生成的java类代码就很复杂。

---

HttpClientBuilder调用WebService接口实现

  @Override
    public JSONObject getDataFromMESSystem(String deviceNumber)  {
       // 根据上面的XSDL文档封装请求参数
       String strParameter = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
               "<soap:Envelope xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\">\n" +
               "  <soap:Body>\n" +
               "    <AAFlow002y xmlns=\"http://tempuri.org/\">\n" +
               "  <LotNo>" + deviceNumber + "</LotNo>\n" +
               "    </AAFlow002y>\n" +
               "   </soap:Body>\n" +
               " </soap:Envelope>";

        // 获取数据，返回的是一个xml格式数据
        String xmlData = doPostSoap(UrlConstant.MES_SERVICE_URL, strParameter, UrlConstant.MES_SOAP_URI);
        JSONObject jsonObject = null;
        try {
            // 将请求结果转换成json类型
            if(StringUtils.isNotBlank(xmlData)){
                jsonObject = xml2Json(xmlData);
            }

        } catch (Exception e) {
            e.printStackTrace();
        }
        return jsonObject;
    }

/**
     * 发送Soap请求，并返回数据
     * @param url  WebService接口地址
     * @param soap 封装的请求参数
     * @param SOAPAction 对应的调用方法uri
     * @return 返回xml数据，用一个字符串接收
     */
    public static String doPostSoap(String url, String soap, String SOAPAction) {
        // 请求体
        String retStr = "";
        // 创建HttpClientBuilder
        HttpClientBuilder httpClientBuilder = HttpClientBuilder.create();
        // HttpClient
        CloseableHttpClient closeableHttpClient = httpClientBuilder.build();
        HttpPost httpPost = new HttpPost(url);
        try {
            httpPost.setHeader("Content-Type", "text/xml;charset=UTF-8");
            httpPost.setHeader("SOAPAction", SOAPAction);
            StringEntity data = new StringEntity(soap,
                    Charset.forName("UTF-8"));
            httpPost.setEntity(data);
            CloseableHttpResponse response = closeableHttpClient
                    .execute(httpPost);
            HttpEntity httpEntity = response.getEntity();
            if (httpEntity != null) {
                // 打印响应内容
                retStr = EntityUtils.toString(httpEntity, "UTF-8");
                System.err.println("response:" + retStr);
            }
            // 释放资源
            closeableHttpClient.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return retStr;
    }

接下来需要根据返回的xml格式数据解析为Json格式，我们可以用Postman测试WebService接口，查看数据返回格式，如下图所示：

点击Send，返回的数据格式如下图所示：

数据太多，这里我给出返回的缩减的结构数据，如下

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
    <soap:Body>
        <AAFlow002yResponse xmlns="http://tempuri.org/">
            <AAFlow002yResult>
                <xs:schema id="NewDataSet" xmlns="" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
                    <xs:element name="NewDataSet" msdata:IsDataSet="true" msdata:MainDataTable="AAFlow002" msdata:UseCurrentLocale="true">
                        <xs:complexType>
                            <xs:choice minOccurs="0" maxOccurs="unbounded">
                                <xs:element name="AAFlow002">
                                    <xs:complexType>
                                        <xs:sequence>
                                            <xs:element name="F1000" type="xs:string" minOccurs="0" />
                                        </xs:sequence>
                                    </xs:complexType>
                                </xs:element>
                            </xs:choice>
                        </xs:complexType>
                    </xs:element>
                </xs:schema>
                <diffgr:diffgram xmlns:msdata="urn:schemas-microsoft-com:xml-msdata" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1">
                    <DocumentElement xmlns="">
                        <AAFlow002 diffgr:id="AAFlow0021" msdata:rowOrder="0">
                                                   <F1000>2596</F1000>
                        </AAFlow002>
                    </DocumentElement>
                </diffgr:diffgram>
            </AAFlow002yResult>
        </AAFlow002yResponse>
    </soap:Body>
</soap:Envelope>

根据上面的信息，编写解析xml数据转换为Json格式数据代码如下：

 /**
     * 解析webservice的返回结果,将xml解析为json格式数据
     * @param xmlStr xml内容
     * @return
     */
    public static JSONObject xml2Json(String xmlStr) throws DocumentException {

        Document doc = DocumentHelper.parseText(xmlStr);
        Element root = doc.getRootElement();
        Element body = root.element("Body");
        Element response = body.element("AAFlow002yResponse");
        Element result = response.element("AAFlow002yResult");
        Element diffgram = result.element(new QName("diffgram", Namespace.get("urn:schemas-microsoft-com:xml-diffgram-v1")));
        Element documentElement = diffgram.element("DocumentElement");
        Element aaFlow002 = documentElement.element("AAFlow002");
        JSONObject jsonObject = new JSONObject();
        Iterator<Element> iterator = aaFlow002.elementIterator();
        while (iterator.hasNext()) {
            Element element = iterator.next();
            jsonObject.put(element.getName(), element.getText());
        }
        return jsonObject;
    }

通过HttpClient的方式调用WebService接口，缺点是需要自己编写解析xml的代码，而WebServiceTemplate的方式可以自动解析为对应的Java类，但是个人更偏向于使用HttpClient的方式调用WebService接口，WebServiceTemplate方式，代码复杂度比较高，耦合性太强。