1． SOAP
a)
原理：SOAP可以理解为另外一种形式的XML-RPC实现，他也是在HTTP的协议体里面附带了所要调用的服务请求，或者服务结果。另外，SOAP可以定义一些额外的变量类型，而不仅是协议所规定的那部分。
另外，SOAP把他的消息封装到一个Envelop当中，Envelop包括了三部分，Header，Body和Attachment。其中Header是XML-RPC所没有的，他提供了一套额外的机制来保证程序的健壮性和安全性。例如mustUnderstand属性保证了服务方清楚了解请求方的要求。version保证不同版本的SOAP之间不会形成调用关系。actor属性，保证了消息能在既定的路线上传输。
2． SOAP的请求和响应格式。
a)
请求：
POST /soap/servlet/rpcrouter HTTP/1.0
Host: localhost:5555
Content-Type: text/xml; charset=utf-8
Content-Length: 440
SOAPAction: ""
<?xml version='1.0'
encoding='UTF-8'?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:xsi=http://www.w3.org/2001/XMLSchema-instance
xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<SOAP-ENV:Body>
<ns1:hello
xmlns:ns1="urn:HelloService"
SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
<name
xsi:type="xsd:string">nick</name>
</ns1:hello>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>
b)
响应：
HTTP/1.1 200 OK
Server: Apache-Coyote/1.1
X-Powered-By: Servlet 2.4; JBoss-
(build: CVSTag=JBoss_4_0_3_RC1 date=200506260220)/Tomcat-5.5
Set-Cookie: JSESSIONID=
Content-Type: text/xml;charset=utf-8
Content-Length: 474
Date: Thu, 25 Aug 2005 01:30:56 GMT
Connection: close
<?xml version='1.0'
encoding='UTF-8'?>
<SOAP-ENV:Envelope
xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:xsi=http://www.w3.org/2001/XMLSchema-instance
xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<SOAP-ENV:Body>
<ns1:helloResponse
xmlns:ns1="urn:HelloService"
SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
<return
xsi:type="xsd:string">Hello World nick</return>
</ns1:helloResponse>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>
c)
错误：
HTTP/1.1 500 Internal Server Error
Server: Apache-Coyote/1.1
X-Powered-By: Servlet 2.4; JBoss-
(build: CVSTag=JBoss_4_0_3_RC1 date=200506260220)/Tomcat-5.5
Set-Cookie: JSESSIONID=2B54BDA0260BA
Content-Type: text/xml;charset=utf-8
Content-Length: 477
Date: Thu, 25 Aug 2005 01:33:59 GMT
Connection: close
<?xml version='1.0'
encoding='UTF-8'?>
<SOAP-ENV:Envelope
xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:xsi=http://www.w3.org/2001/XMLSchema-instance
xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<SOAP-ENV:Body>
<SOAP-ENV:Fault>
<faultcode>SOAP-ENV:Server</faultcode>
<faultstring>Method "hello2"
is not supported.</faultstring>
<faultactor>/soap/servlet/rpcrouter</faultactor>
</SOAP-ENV:Fault>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>
3． SOAP实例
a)
发送请求：
public class Client {
public
static void main(String[] args) throws Exception {
URL
url = new URL("http://localhost:8080/soap/servlet/rpcrouter");
Call
call = new Call();
call.setTargetObjectURI("urn:HelloService");
call.setMethodName("hello");
call.setEncodingStyleURI(Constants.NS_URI_SOAP_ENC);
Vector<Parameter>
pars = new Vector<Parameter>();
pars.addElement(new
Parameter("name", String.class, "nick", null));
call.setParams(pars);
Response
res = call.invoke(url, "");
if
(!res.generatedFault()) {
Parameter
par = res.getReturnValue();
System.out.println(par.getValue());
}else{
Fault
fault = res.getFault();
System.out.println(fault);
}
}
}
b)
发布服务：apache-soap是通过一个XML文件，来描述所要发布的服务的。
<?xml version="1.0"?>
<isd:service xmlns:isd=http://xml.apache.org/xml-soap/deployment
id="urn:HelloService">
<isd:provider type="java" scope="Application" methods="hello">
<isd:java class="test.Service" static="false"/>
</isd:provider>
<isd:faultListener>org.apache.soap.server.DOMFaultListener</isd:faultListener>
</isd:service>