springboot-webservice

文档摘要：

Why Contract First?

When creating Web services, there are two development styles: Contract Last and Contract First. When using a contract-last approach, you start with the Java code, and let the Web service contract (WSDL, see sidebar) be generated from that. When using contract-first, you start with the WSDL contract, and use Java to implement said contract.

Spring-WS only supports the contract-first development style

why contract-first？主要是讲了Object/XML mapping的问题.就不详细摘录了。

When using contract-first, you explicitly describe what XML is sent where, thus making sure that it is exactly what you want.

Writing Contract-First Web Services

contract-first Web services, that is, developing web services that start with the XML Schema/WSDL contract first followed by the Java code second.

xml message:

使用约束：XML Schema(XSD)

<dependencies>
    <dependency>
        <groupId>org.springframework.ws</groupId>
        <artifactId>spring-ws-core</artifactId>
        <version></version>
    </dependency>
    <dependency>
        <groupId>jdom</groupId>
        <artifactId>jdom</artifactId>
        <version>2.0.1</version>
    </dependency>
    <dependency>
        <groupId>jaxen</groupId>
        <artifactId>jaxen</artifactId>
        <version>1.1</version>
    </dependency>
</dependencies>

We also instruct Spring-WS to use annotation-driven endpoints, with the <sws:annotation-driven>element.

package com.mycompany.hr.ws;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Arrays;
import java.util.Date;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.ws.server.endpoint.annotation.Endpoint;
import org.springframework.ws.server.endpoint.annotation.PayloadRoot;
import org.springframework.ws.server.endpoint.annotation.RequestPayload;

import com.mycompany.hr.service.HumanResourceService;
import org.jdom2.Element;
import org.jdom2.JDOMException;
import org.jdom2.Namespace;
import org.jdom2.filter.Filters;
import org.jdom2.xpath.XPathExpression;
import org.jdom2.xpath.XPathFactory;

@Endpoint                                                                                     
public class HolidayEndpoint {

    private static final String NAMESPACE_URI = "http://mycompany.com/hr/schemas";

    private XPathExpression<Element> startDateExpression;

    private XPathExpression<Element> endDateExpression;

    private XPathExpression<Element> firstNameExpression;

    private XPathExpression<Element> lastNameExpression;

    private HumanResourceService humanResourceService;

    @Autowired                                                                                
    public HolidayEndpoint(HumanResourceService humanResourceService) throws JDOMException {
        this.humanResourceService = humanResourceService;

        Namespace namespace = Namespace.getNamespace("hr", NAMESPACE_URI);
        XPathFactory xPathFactory = XPathFactory.instance();
        startDateExpression = xPathFactory.compile("//hr:StartDate", Filters.element(), null, namespace);
        endDateExpression = xPathFactory.compile("//hr:EndDate", Filters.element(), null, namespace);
        firstNameExpression = xPathFactory.compile("//hr:FirstName", Filters.element(), null, namespace);
        lastNameExpression = xPathFactory.compile("//hr:LastName", Filters.element(), null, namespace);
    }

    @PayloadRoot(namespace = NAMESPACE_URI, localPart = "HolidayRequest")                      
    public void handleHolidayRequest(@RequestPayload Element holidayRequest) throws Exception {
        Date startDate = parseDate(startDateExpression, holidayRequest);
        Date endDate = parseDate(endDateExpression, holidayRequest);
        String name = firstNameExpression.evaluateFirst(holidayRequest).getText() + " " + lastNameExpression.evaluateFirst(holidayRequest).getText();

        humanResourceService.bookHoliday(startDate, endDate, name);
    }

    private Date parseDate(XPathExpression<Element> expression, Element element) throws ParseException {
        Element result = expression.evaluateFirst(element);
        if (result != null) {
            SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
            return dateFormat.parse(result.getText());
        } else {
            throw new IllegalArgumentException("Could not evaluate [" + expression + "] on [" + element + "]");
        }
    }

}