How to do a SOAP Web Service call from Java class?

I'm relative new to the webservices world and my research seems to have confused me more than enlighten me, my problem is that I was given a library(jar) which I have to extend with some webservice functionality.

This library will be shared to other developers, and among the classes in the jar will be classes that have a method which calls a webservice (that essentially sets an attribute of the class, does some business logic, like storing the object in a db, etc and sends back the object with those modifications). I want to make the call to this service as simple as possible, hopefully as simple so that the developer using the class only need to do.

Car c = new Car("Blue");
c.webmethod();

I have been studying JAX-WS to use on the server but seems to me that I don't need to create a wsimport in the server nor the wsimport on the client, since I know that both have the classes, I just need some interaction between classes shared in both the server and the client. How do you think makes sense to do the webservice and the call in the class?

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最佳答案

我明白你的问题归结为 如何从 Java 调用 SOAP (JAX-WS) Web 服务并获取其返回对象。在这种情况下，你有两种可能的方法:

  1. 通过 wsimport生成 Java 类并使用它们; 或者
  2. 创建一个 SOAP 客户端:
    1. 将服务的参数序列化为 XML;
    2. 通过 HTTP 操作调用 web 方法; 以及
    3. Parse the returning XML response back into an object.


关于第一种方法(使用 wsimport) :

I see you already have the services' (entities or other) business classes, and it's a fact that the wsimport generates a whole new set of classes (that are somehow duplicates of the classes you already have).

不过，在这种情况下，恐怕你只能选择:

  • 改编(编辑) wsimport生成的代码，使其使用 你的业务类(这很困难，而且不知何故不值得——请记住每次 WSDL 更改时，您都必须重新生成并重新改编代码) ; 或者
  • 放弃使用 wsimport生成的类。(在这个解决方案中，业务代码可以“使用”生成的类作为来自另一个体系结构层的服务。)

关于第二种方法(创建自定义 SOAP 客户端) :

为了实现第二种方法，你必须:

  1. 打电话:
    • 使用 SAAJ (SAAJ)框架(见下文，它与 Java SE 1.6或更高版本一起提供)进行调用; 或者
    • 您也可以通过 java.net.HttpUrlconnection(和一些 java.io处理)来完成。
  2. 将对象转换为 XML 或从 XML 转换回来:
    • 使用诸如 JAXB 之类的 OXM (Object to XML Mapping)框架将 XML 从对象序列化/反序列化为对象
    • 或者，如果必须的话，手动创建/解析 XML (如果接收到的对象与发送的对象只有一点点不同，那么这可能是最好的解决方案)。

使用经典的 java.net.HttpUrlConnection创建 SOAP 客户机并不是那么困难(但也不是那么简单) ，您可以在 这个链接中找到非常好的起始代码。

我建议您使用 SAAJ 框架:

SAAJ (SAAJ) 主要用于直接处理发生在任何 Web 服务 API 幕后的 SOAP 请求/响应消息。它允许开发人员直接发送和接收肥皂消息，而不必使用 JAX-WS。

下面是一个使用 SAAJ 的 SOAPWeb 服务调用的工作示例(运行它!) ，它调用 网上服务。

import javax.xml.soap.*;


public class SOAPClientSAAJ {


// SAAJ - SOAP Client Testing
public static void main(String args[]) {
/*
The example below requests from the Web Service at:
https://www.w3schools.com/xml/tempconvert.asmx?op=CelsiusToFahrenheit




To call other WS, change the parameters below, which are:
- the SOAP Endpoint URL (that is, where the service is responding from)
- the SOAP Action


Also change the contents of the method createSoapEnvelope() in this class. It constructs
the inner part of the SOAP envelope that is actually sent.
*/
String soapEndpointUrl = "https://www.w3schools.com/xml/tempconvert.asmx";
String soapAction = "https://www.w3schools.com/xml/CelsiusToFahrenheit";


callSoapWebService(soapEndpointUrl, soapAction);
}


private static void createSoapEnvelope(SOAPMessage soapMessage) throws SOAPException {
SOAPPart soapPart = soapMessage.getSOAPPart();


String myNamespace = "myNamespace";
String myNamespaceURI = "https://www.w3schools.com/xml/";


// SOAP Envelope
SOAPEnvelope envelope = soapPart.getEnvelope();
envelope.addNamespaceDeclaration(myNamespace, myNamespaceURI);


/*
Constructed SOAP Request Message:
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:myNamespace="https://www.w3schools.com/xml/">
<SOAP-ENV:Header/>
<SOAP-ENV:Body>
<myNamespace:CelsiusToFahrenheit>
<myNamespace:Celsius>100</myNamespace:Celsius>
</myNamespace:CelsiusToFahrenheit>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>
*/


// SOAP Body
SOAPBody soapBody = envelope.getBody();
SOAPElement soapBodyElem = soapBody.addChildElement("CelsiusToFahrenheit", myNamespace);
SOAPElement soapBodyElem1 = soapBodyElem.addChildElement("Celsius", myNamespace);
soapBodyElem1.addTextNode("100");
}


private static void callSoapWebService(String soapEndpointUrl, String soapAction) {
try {
// Create SOAP Connection
SOAPConnectionFactory soapConnectionFactory = SOAPConnectionFactory.newInstance();
SOAPConnection soapConnection = soapConnectionFactory.createConnection();


// Send SOAP Message to SOAP Server
SOAPMessage soapResponse = soapConnection.call(createSOAPRequest(soapAction), soapEndpointUrl);


// Print the SOAP Response
System.out.println("Response SOAP Message:");
soapResponse.writeTo(System.out);
System.out.println();


soapConnection.close();
} catch (Exception e) {
System.err.println("\nError occurred while sending SOAP Request to Server!\nMake sure you have the correct endpoint URL and SOAPAction!\n");
e.printStackTrace();
}
}


private static SOAPMessage createSOAPRequest(String soapAction) throws Exception {
MessageFactory messageFactory = MessageFactory.newInstance();
SOAPMessage soapMessage = messageFactory.createMessage();


createSoapEnvelope(soapMessage);


MimeHeaders headers = soapMessage.getMimeHeaders();
headers.addHeader("SOAPAction", soapAction);


soapMessage.saveChanges();


/* Print the request message, just for debugging purposes */
System.out.println("Request SOAP Message:");
soapMessage.writeTo(System.out);
System.out.println("\n");


return soapMessage;
}


}

About using JAXB for serializing/deserializing, it is very easy to find information about it. You can start here: http://www.mkyong.com/java/jaxb-hello-world-example/.

小开

或者仅仅使用 Apache CXF 的 wsdl2java来生成您可以使用的对象。

它包含在二进制软件包中，你可以从他们的网站下载。您可以简单地运行如下命令:

$ ./wsdl2java -p com.mynamespace.for.the.api.objects -autoNameResolution http://www.someurl.com/DefaultWebService?wsdl

它使用 wsdl 来生成对象，您可以像使用 this一样使用它(对象名称也是从 wsdl 中获取的，因此您的对象名称会有一点不同) :

DefaultWebService defaultWebService = new DefaultWebService();
String res = defaultWebService.getDefaultWebServiceHttpSoap11Endpoint().login("webservice","dadsadasdasd");
System.out.println(res);

甚至还有一个生成源代码的 Maven 插件: https://cxf.apache.org/docs/maven-cxf-codegen-plugin-wsdl-to-java.html

注意: 如果您使用 CXF 和 IDEA 生成源代码，您可能想看看以下内容: https://stackoverflow.com/a/46812593/840315

小开

我找到了一种更简单的生成肥皂信息的方法。 给定一个人物对象:

import com.fasterxml.jackson.annotation.JsonInclude;


@JsonInclude(JsonInclude.Include.NON_NULL)
public class Person {
private String name;
private int age;
private String address; //setter and getters below
}

下面是一个简单的肥皂消息生成器:

import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import com.fasterxml.jackson.dataformat.xml.XmlMapper;


@Slf4j
public class SoapGenerator {


protected static final ObjectMapper XML_MAPPER = new XmlMapper()
.enable(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_AS_NULL)
.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
.configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false)
.registerModule(new JavaTimeModule());


private static final String SOAP_BODY_OPEN = "<soap:Body>";
private static final String SOAP_BODY_CLOSE = "</soap:Body>";
private static final String SOAP_ENVELOPE_OPEN = "<soap:Envelope xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\">";
private static final String SOAP_ENVELOPE_CLOSE = "</soap:Envelope>";


public static String soapWrap(String xml) {
return SOAP_ENVELOPE_OPEN + SOAP_BODY_OPEN + xml + SOAP_BODY_CLOSE + SOAP_ENVELOPE_CLOSE;
}


public static String soapUnwrap(String xml) {
return StringUtils.substringBetween(xml, SOAP_BODY_OPEN, SOAP_BODY_CLOSE);
}
}

你可以使用:

 public static void main(String[] args) throws Exception{
Person p = new Person();
p.setName("Test");
p.setAge(12);


String xml = SoapGenerator.soapWrap(XML_MAPPER.writeValueAsString(p));
log.info("Generated String");
log.info(xml);
}
小开

对于将 xml 请求作为字符串的人可能有帮助。 if you have WSDL, You can create a new soap request in SoapUI with that WSDL file.
它会自动为输入请求生成结构/XML。

如果您有来自 SoapUI 的输入请求 xml，可以使用下面这些简单的 Java 代码来调用 Soap 服务:

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;


public class SimpleSoapClient {


public static void main(String args[]) throws IOException {
        

String address="Hyderabad";


/* place your xml request from soap ui below with necessary changes in parameters*/
    

String xml="<soapenv:Envelope xmlns:soapenv=\"http://schemas.xmlsoap.org/soap/envelope/\" xmlns:ws=\"http://www.YourUrlAsPerWsdl.com/\">\r\n" +
"   <soapenv:Header/>\r\n" +
"   <soapenv:Body>\r\n" +
"      <ws:callRest>\r\n" +
"         <name>"+"Hello"+"</name>\r\n" +
"         <address>"+address+"</address>\r\n" +
"      </ws:callRest>\r\n" +
"   </soapenv:Body>\r\n" +
"</soapenv:Envelope>";
String responseF=callSoapService(xml);
System.out.println(responseF);
}
    



}


static String callSoapService(String soapRequest) {
try {
String url = "https://gogle.com/service/hello"; // replace your URL here
URL obj = new URL(url);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
     

// change these values as per soapui request on top left of request, click on RAW, you will find all the headers
con.setRequestMethod("POST");
con.setRequestProperty("Content-Type","text/xml; charset=utf-8");
con.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(con.getOutputStream());
wr.writeBytes(soapRequest);
wr.flush();
wr.close();
String responseStatus = con.getResponseMessage();
System.out.println(responseStatus);
BufferedReader in = new BufferedReader(new InputStreamReader(
con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
     

// You can play with response which is available as string now:
String finalvalue= response.toString();
     

// or you can parse/substring the required tag from response as below based your response code
finalvalue= finalvalue.substring(finalvalue.indexOf("<response>")+10,finalvalue.indexOf("</response>")); */
     

return finalvalue;
}
catch (Exception e) {
return e.getMessage();
}
}

}


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