Consuming a SOAP web service

This guide walks you through the process of consuming a SOAP-based web service with Spring.

What You Will Build

You will build a client that fetches country data from a remote, WSDL-based web service by using SOAP. You can find out more about the country service and run the service yourself by following this guide.

The service provides country data. You will be able to query data about a country based on its name.

What You Need

How to complete this guide

Like most Spring Getting Started guides, you can start from scratch and complete each step or you can bypass basic setup steps that are already familiar to you. Either way, you end up with working code.

To start from scratch, move on to Starting with Spring Initializr.

To skip the basics, do the following:

When you finish, you can check your results against the code in gs-consuming-web-service/complete.

Run the Target Web Service Locally

Follow the steps in the companion guide or clone the repository and run the service (for example, by using mvn spring-boot:run) from its complete directory. You can verify that it works by visiting http://localhost:8080/ws/countries.wsdl in your browser. If you do not do so, you will see a confusing exception in your build later from the JAXB tooling.

Starting with Spring Initializr

For all Spring applications, you should start with the Spring Initializr. The Initializr offers a fast way to pull in all the dependencies you need for an application and does a lot of the setup for you. This example needs only the Spring Web Services dependency.

You can use this pre-initialized project and click Generate to download a ZIP file. This project is configured to fit the examples in this tutorial.

To initialize the project:

  1. Navigate to https://start.spring.io. This service pulls in all the dependencies you need for an application and does most of the setup for you.

  2. Choose either Gradle or Maven and the language you want to use. This guide assumes that you chose Java.

  3. Click Dependencies and select Spring Web Services.

  4. Click Generate.

  5. Download the resulting ZIP file, which is an archive of a web application that is configured with your choices.

If your IDE has the Spring Initializr integration, you can complete this process from your IDE.
You can also fork the project from Github and open it in your IDE or other editor.

Modify the Build Files

The build files created by the Spring Initializr need quite a bit of work for this guide. Also, the modifications to pom.xml (for Maven) and build.gradle (for Gradle) differ substantially.

Maven

For Maven, you need to add a dependency, a profile, and a WSDL generation plugin.

The following listing shows the dependency you need to add in Maven:

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

The Generate Domain Objects Based on a WSDL section describes the WSDL generation plugin.

The following listing shows the final pom.xml file:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>3.2.0</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.example</groupId>
	<artifactId>consuming-web-service-complete</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>consuming-web-service-complete</name>
	<description>Demo project for Spring Boot</description>

	<properties>
		<java.version>17</java.version>
	</properties>

	<dependencies>
		<!-- tag::dependency[] -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web-services</artifactId>
			<exclusions>
				<exclusion>
					<groupId>org.springframework.boot</groupId>
					<artifactId>spring-boot-starter-tomcat</artifactId>
				</exclusion>
			</exclusions>
		</dependency>
		<!-- end::dependency[] -->

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
			<!-- tag::wsdl[] -->
			<plugin>
				<groupId>com.sun.xml.ws</groupId>
				<artifactId>jaxws-maven-plugin</artifactId>
				<version>3.0.0</version>
				<executions>
					<execution>
						<goals>
							<goal>wsimport</goal>
						</goals>
					</execution>
				</executions>
				<configuration>
					<packageName>com.example.consumingwebservice.wsdl</packageName>
					<wsdlUrls>
						<wsdlUrl>http://localhost:8080/ws/countries.wsdl</wsdlUrl>
					</wsdlUrls>
					<sourceDestDir>${sourcesDir}</sourceDestDir>
					<destDir>${classesDir}</destDir>
					<extension>true</extension>
				</configuration>
			</plugin>
			<!-- end::wsdl[] -->
		</plugins>
	</build>

</project>

Gradle

For Gradle, you need to add a dependency, a configuration, a bootJar section, and a WSDL generation plugin.

The following listing shows the dependency you need to add in Gradle:

implementation ('org.springframework.boot:spring-boot-starter-web-services') {
	exclude group: 'org.springframework.boot', module: 'spring-boot-starter-tomcat'
}
jaxws 'com.sun.xml.ws:jaxws-tools:3.0.0',
		'jakarta.xml.ws:jakarta.xml.ws-api:3.0.0',
		'jakarta.xml.bind:jakarta.xml.bind-api:3.0.0',
		'jakarta.activation:jakarta.activation-api:2.0.0',
		'com.sun.xml.ws:jaxws-rt:3.0.0'

Note the exclusion of Tomcat. If Tomcat is allowed to run in this build, you get a port collision with the Tomcat instance that provides the country data.

Due to this port collision, the initial project fails to start. You can fix it by adding an application.properties file with a single property of server.port=8081. Since the initial project exists to be a starting point, you can skip trying to get it to run.

The Generate Domain Objects Based on a WSDL section describes the WSDL generation plugin.

The following listing shows the final build.gradle file:

plugins {
	id 'java'
	id 'org.springframework.boot' version '3.2.0'
	id 'io.spring.dependency-management' version '1.1.4'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
java {
	sourceCompatibility = '17'
}
ext.jaxwsSourceDir = "${buildDir}/generated/sources/jaxws"

// tag::configurations[]
configurations {
	jaxws
}
// end::configurations[]

repositories {
	mavenCentral()
}

// tag::wsdl[]
task wsimport {
	description = 'Generate classes from wsdl using wsimport'

	doLast {
		project.mkdir(jaxwsSourceDir)
		ant {
			taskdef(name: 'wsimport',
					classname: 'com.sun.tools.ws.ant.WsImport',
					classpath: configurations.jaxws.asPath
			)
			wsimport(
					keep: true,
					destdir: jaxwsSourceDir,
					extension: "true",
					verbose: true,
					wsdl: "http://localhost:8080/ws/countries.wsdl",
					xnocompile: true,
					package: "com.example.consumingwebservice.wsdl") {
				xjcarg(value: "-XautoNameResolution")
			}
		}
	}
}

sourceSets {
	main {
		java.srcDirs += jaxwsSourceDir
	}
}

compileJava {
	dependsOn wsimport
}
// end::wsdl[]

dependencies {
// tag::dependency[]
	implementation ('org.springframework.boot:spring-boot-starter-web-services') {
		exclude group: 'org.springframework.boot', module: 'spring-boot-starter-tomcat'
	}
	jaxws 'com.sun.xml.ws:jaxws-tools:3.0.0',
			'jakarta.xml.ws:jakarta.xml.ws-api:3.0.0',
			'jakarta.xml.bind:jakarta.xml.bind-api:3.0.0',
			'jakarta.activation:jakarta.activation-api:2.0.0',
			'com.sun.xml.ws:jaxws-rt:3.0.0'
// end::dependency[]
	testImplementation('org.springframework.boot:spring-boot-starter-test')
}

tasks.named('test') {
	useJUnitPlatform()
}

Generate Domain Objects Based on a WSDL

The interface to a SOAP web service is captured in WSDL. JAXB provides a way to generate Java classes from WSDL (or rather, the XSD contained in the <Types/> section of the WSDL). You can find the WSDL for the country service at http://localhost:8080/ws/countries.wsdl.

To generate Java classes from the WSDL in Maven, you need the following plugin setup:

<plugin>
	<groupId>com.sun.xml.ws</groupId>
	<artifactId>jaxws-maven-plugin</artifactId>
	<version>3.0.0</version>
	<executions>
		<execution>
			<goals>
				<goal>wsimport</goal>
			</goals>
		</execution>
	</executions>
	<configuration>
		<packageName>com.example.consumingwebservice.wsdl</packageName>
		<wsdlUrls>
			<wsdlUrl>http://localhost:8080/ws/countries.wsdl</wsdlUrl>
		</wsdlUrls>
		<sourceDestDir>${sourcesDir}</sourceDestDir>
		<destDir>${classesDir}</destDir>
		<extension>true</extension>
	</configuration>
</plugin>

This setup generates classes for the WSDL found at the specified URL, putting those classes in the com.example.consumingwebservice.wsdl package. To generate that code run, ./mvnw compile and then look in target/generated-sources if you want to check that it worked.

To do the same with Gradle, you need the following in your build file:

task wsimport {
  description = 'Generate classes from wsdl using wsimport'

  doLast {
    project.mkdir(jaxwsSourceDir)
    ant {
      taskdef(name: 'wsimport',
          classname: 'com.sun.tools.ws.ant.WsImport',
          classpath: configurations.jaxws.asPath
      )
      wsimport(
          keep: true,
          destdir: jaxwsSourceDir,
          extension: "true",
          verbose: true,
          wsdl: "http://localhost:8080/ws/countries.wsdl",
          xnocompile: true,
          package: "com.example.consumingwebservice.wsdl") {
        xjcarg(value: "-XautoNameResolution")
      }
    }
  }
}

sourceSets {
  main {
    java.srcDirs += jaxwsSourceDir
  }
}

compileJava {
  dependsOn wsimport
}

As Gradle does not (yet) have a JAXB plugin, it involves an Ant task, which makes it a bit more complex than in Maven. To generate that code run ./gradlew compileJava and then look in build/generated-sources if you want to check that it worked.

In both Maven and Gradle, the JAXB domain object generation process has been wired into the build tool’s lifecycle, so you need not run any extra steps once you have a successful build.

Create a Country Service Client

To create a web service client, you have to extend the WebServiceGatewaySupport class and code your operations, as the following example (from src/main/java/com/example/consumingwebservice/CountryClient.java) shows:

package com.example.consumingwebservice;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.springframework.ws.client.core.support.WebServiceGatewaySupport;
import org.springframework.ws.soap.client.core.SoapActionCallback;

import com.example.consumingwebservice.wsdl.GetCountryRequest;
import com.example.consumingwebservice.wsdl.GetCountryResponse;

public class CountryClient extends WebServiceGatewaySupport {

  private static final Logger log = LoggerFactory.getLogger(CountryClient.class);

  public GetCountryResponse getCountry(String country) {

    GetCountryRequest request = new GetCountryRequest();
    request.setName(country);

    log.info("Requesting location for " + country);

    GetCountryResponse response = (GetCountryResponse) getWebServiceTemplate()
        .marshalSendAndReceive("http://localhost:8080/ws/countries", request,
            new SoapActionCallback(
                "http://spring.io/guides/gs-producing-web-service/GetCountryRequest"));

    return response;
  }

}

The client contains one method (getCountry) that does the actual SOAP exchange.

In this method, both the GetCountryRequest and the GetCountryResponse classes are derived from the WSDL and were generated in the JAXB generation process (described in Generate Domain Objects Based on a WSDL). It creates the GetCountryRequest request object and sets it up with the country parameter (the name of the country). After printing out the country name, it uses the WebServiceTemplate supplied by the WebServiceGatewaySupport base class to do the actual SOAP exchange. It passes the GetCountryRequest request object (as well as a SoapActionCallback to pass on a SOAPAction header with the request) as the WSDL described that it needed this header in the <soap:operation/> elements. It casts the response into a GetCountryResponse object, which is then returned.

Configuring Web Service Components

Spring WS uses Spring Framework’s OXM module, which has the Jaxb2Marshaller to serialize and deserialize XML requests, as the following example (from src/main/java/com/example/consumingwebservice/CountryConfiguration.java) shows:

package com.example.consumingwebservice;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.oxm.jaxb.Jaxb2Marshaller;

@Configuration
public class CountryConfiguration {

  @Bean
  public Jaxb2Marshaller marshaller() {
    Jaxb2Marshaller marshaller = new Jaxb2Marshaller();
    // this package must match the package in the <generatePackage> specified in
    // pom.xml
    marshaller.setContextPath("com.example.consumingwebservice.wsdl");
    return marshaller;
  }

  @Bean
  public CountryClient countryClient(Jaxb2Marshaller marshaller) {
    CountryClient client = new CountryClient();
    client.setDefaultUri("http://localhost:8080/ws");
    client.setMarshaller(marshaller);
    client.setUnmarshaller(marshaller);
    return client;
  }

}

The marshaller is pointed at the collection of generated domain objects and will use them to both serialize and deserialize between XML and POJOs.

The countryClient is created and configured with the URI of the country service shown earlier. It is also configured to use the JAXB marshaller.

Run the Application

This application is packaged up to run from the console and retrieve the data for a given country name, as the following listing (from src/main/java/com/example/consumingwebservice/ConsumingWebServiceApplication.java) shows:

package com.example.consumingwebservice;

import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;

import com.example.consumingwebservice.wsdl.GetCountryResponse;

@SpringBootApplication
public class ConsumingWebServiceApplication {

  public static void main(String[] args) {
    SpringApplication.run(ConsumingWebServiceApplication.class, args);
  }

  @Bean
  CommandLineRunner lookup(CountryClient countryClient) {
    return args -> {
      String country = "Spain";

      if (args.length > 0) {
        country = args[0];
      }
      GetCountryResponse response = countryClient.getCountry(country);
      System.err.println(response.getCountry().getCurrency());
    };
  }

}

The main() method defers to the SpringApplication helper class, providing CountryConfiguration.class as an argument to its run() method. This tells Spring to read the annotation metadata from CountryConfiguration and to manage it as a component in the Spring application context.

This application is hard-coded to look up 'Spain'. Later in this guide, you will see how to enter a different symbol without editing the code.

Build an executable JAR

You can run the application from the command line with Gradle or Maven. You can also build a single executable JAR file that contains all the necessary dependencies, classes, and resources and run that. Building an executable jar makes it easy to ship, version, and deploy the service as an application throughout the development lifecycle, across different environments, and so forth.

If you use Gradle, you can run the application by using ./gradlew bootRun. Alternatively, you can build the JAR file by using ./gradlew build and then run the JAR file, as follows:

java -jar build/libs/gs-consuming-web-service-0.1.0.jar

If you use Maven, you can run the application by using ./mvnw spring-boot:run. Alternatively, you can build the JAR file with ./mvnw clean package and then run the JAR file, as follows:

java -jar target/gs-consuming-web-service-0.1.0.jar
The steps described here create a runnable JAR. You can also build a classic WAR file.

Logging output is displayed. The service should be up and running within a few seconds.

The following listing shows the initial response:

Requesting country data for Spain

<getCountryRequest><name>Spain</name>...</getCountryRequest>

You can plug in a different country by running the following command:

java -jar build/libs/gs-consuming-web-service-0.1.0.jar Poland

Then the response changes to the following:

Requesting location for Poland

<getCountryRequest><name>Poland</name>...</getCountryRequest>

Summary

Congratulations! You have just developed a client to consume a SOAP-based web service with Spring.

See Also

The following guides may also be helpful:

Want to write a new guide or contribute to an existing one? Check out our contribution guidelines.

All guides are released with an ASLv2 license for the code, and an Attribution, NoDerivatives creative commons license for the writing.

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