使用Axis2的底层API开发Web Service
2010-06-07 10:26
357 查看
本文是在理解官方指南的基础上,用实例实现Axis2提供的4种调用机制,并给出测试结果。
1.使用Axis2的底层API开发Web Service Server端
1.1
创建一个WebService(取名为MyService)
在MyService中有两个operations,如下所示。
public void ping(OMElement
element){}//IN-ONLY模式。仅仅接收OMElement,并对其处理。
public OMElement
echo(OMElement element){}//IN_OUT模式。接收OMElemen,并返回OMElement。
1.2如何写Web Service
1)创建实现服务的类。
2)创建services.xml来解析这个Web Service。
3)将其打包成一个*.aar文档(Axis Archive)。
4)部署Web Service。
1.2.1 创建实现服务的类
此类中提供的方法必须与Web
Service(在services.xml中声明)中的operations对应。除非你提供了数据绑定,否则所有的方法只能接收一个参数,其类型为
OMElement。
public class MyService{
public void
ping(OMElement element){...}
public OMElement echo(OMElement
element){...}
}
MyService.java
package userguide.example1;
import org.apache.axiom.om.OMElement;
import
org.apache.axis2.AxisFault;
import
javax.xml.stream.XMLStreamException;
public class MyService {
public OMElement
echo(OMElement element) throws XMLStreamException {
//Praparing the OMElement so that it can be attached to another OM Tree.
//First the OMElement should be completely build in case it is not
fully built and still
//some of the xml is in the stream.
element.build();
//Secondly the OMElement should be detached
from the current OMTree so that it can
// be attached some
other OM Tree. Once detached the OmTree will remove its
//
connections to this OMElement.
element.detach();
return element;
}
public void ping(OMElement element)
throws XMLStreamException {
//Do some processing
}
public void pingF(OMElement element) throws AxisFault{
throw
new AxisFault("Fault being thrown");
}
}
1.2.2 创建services.xml
Axis2使用services.xml来充当一个Web Servicea的配置文件。每一个使用Axis2部署的Web
Service都必须拥有一个services.xml。
<services>
<description>
This is a sample Web Service with two operations,echo and ping.
</description>
<parameter name=”ServiceClass”
locked=”false”>
userguide.example1.MyService
</parameter>
<operation name=”echo”>
<messageReceiver
class=”org.apache.axis2.receivers.RawXMLINOutMessageReceiver”/>
<actionMapping>urn:echo</actionMapping>
</operation>
<operation name=”ping”>
<messageReceiver
class=”org.apache.receivers.RawXMLINOnlyMessageReceiver”/>
<actionMapping>urn:ping</actionMapping>
</operation>
</service>
注:The
actionMapping is required only if you want to enable WS-Addressing.
可以创建一个services.xml,其中包含一组服务。这样在运行期,你可以在这些服务间共享信息。
<serviceGroup>
<service
name=”Service1”>
<!--details for Services1-->
</service>
<service name=”Service2”>
<!--details for Services2-->
</service>
<module
ref=”ModuleName”/>
<parameter name=”serviceGroupParam1”
locked=”false”>value1</parameter>
</serviceGroup>
注:name
of the service is a compulsory attribute.
1.2.3打包与部署
这里不再详述,参见《
基于Tomcat5.0和Axis2开发Web
Service应用实例
》。
2.使用Axis2底层APIs实现Web Service客户端
2.1ClientUtil
创建一个客户端通用的SOAP包装Util文件。封装"getEchoOMElement"和"getPingOMElement"分别对应"echo"
和"ping"这两个operation。
ClientUtil.java
package userguide.clients;
import org.apache.axiom.om.OMAbstractFactory;
import
org.apache.axiom.om.OMElement;
import org.apache.axiom.om.OMFactory;
import
org.apache.axiom.om.OMNamespace;
public class ClientUtil {
public static
OMElement getEchoOMElement() {
OMFactory fac =
OMAbstractFactory.getOMFactory();
OMNamespace omNs =
fac.createOMNamespace(
"
http://example1.org/example1
", "example1");
OMElement method =
fac.createOMElement("echo", omNs);
OMElement value =
fac.createOMElement("Text", omNs);
value.addChild(fac.createOMText(value, "Axis2 Echo String "));
method.addChild(value);
return method;
}
public static OMElement getPingOMElement() {
OMFactory fac =
OMAbstractFactory.getOMFactory();
OMNamespace omNs =
fac.createOMNamespace(
"
http://example1.org/example1
", "example1");
OMElement method =
fac.createOMElement("ping", omNs);
OMElement value =
fac.createOMElement("Text", omNs);
value.addChild(fac.createOMText(value, "Axis2 Ping String "));
method.addChild(value);
return method;
}
}
2.2EchoBlockingClient
Axis2向用户提供了从blocking
single channel调用到non-blocking dual channel调用的多种调用Web
Service的模式。下面用最简单的blocking调用机制来实现”MyService”中的"echo" operation。
EchoBlockingClient.java
package userguide.clients;
import org.apache.axiom.om.OMElement;
import
org.apache.axis2.AxisFault;
import
org.apache.axis2.addressing.EndpointReference;
import
org.apache.axis2.client.Options;
import
org.apache.axis2.client.ServiceClient;
/**
* Sample for synchronous single channel
blocking service invocation.
* Message Exchage Pattern IN-OUT
*/
public
class EchoBlockingClient {
private static EndpointReference
targetEPR =
new EndpointReference("
http://localhost:8080/axis2/services/MyService
");
public static void main(String[] args) {
try {
OMElement payload = ClientUtil.getEchoOMElement();
Options options = new Options();
options.setTo(targetEPR); // this sets the location of MyService
service
ServiceClient serviceClient = new
ServiceClient();
serviceClient.setOptions(options);
OMElement result = sender.sendReceive(payload);
System.out.println(result);
} catch (AxisFault axisFault) {
axisFault.printStackTrace();
}
}
绿色部分显示了为了调用一个Web
Service而需要对operation作的设置。剩下的部分是用来创建OMElement,用来发送和显示相应的OMElement。
结果:
<example1:echo xmlns:example1="
http://example1.org/example1
"
xmlns:tns="
http://ws.apache.org/axis2
">
<example1:Text>
Axis2
Echo String
</example1:Text>
</example1:echo>
2.3 PingClient
在”MyService”中,我们有一种IN-ONLY模式的名为"ping"的operation。应用它的客户端代码如下:
PingClient.java
package userguide.clients;
import org.apache.axiom.om.OMElement;
import
org.apache.axis2.AxisFault;
import
org.apache.axis2.addressing.EndpointReference;
import
org.apache.axis2.client.Options;
import
org.apache.axis2.client.ServiceClient;
/**
* Sample for fire-and-forget service
invocation
* Message Exchage Pattern IN-Only
*/
public class
PingClient {
private static EndpointReference targetEPR =
new
EndpointReference("
http://localhost:8080/axis2/services/MyService
");
public static void main(String[] args) {
try {
OMElement payload = ClientUtil.getPingOMElement();
Options
options = new Options();
options.setTo(targetEPR);
ServiceClient serviceClient = new ServiceClient();
serviceClient.setOptions(options);
serviceClient.fireAndForget(payload);
/**
* We have to block this thread untill we send the
request , the problem
* is if we go out of the main thread ,
then request wont send ,so
* you have to wait some time :)
*/
Thread.sleep(500);
}
catch (AxisFault
axisFault) {
axisFault.printStackTrace();
}
}
由于我们在访问一个IN-ONLY模式的operation,所以我们可以直接使用ServiceClient中的"fireAndForget()"方
法来调用这个operation。而且那样做的话,不会阻塞发起端,因此,它会立刻将控制权返回给客户端。
2.4 EchoNonBlockingClient
在客户端EchoBlockingClient,一旦调用"serviceClient.sendReceive(payload);",客户端将会被阻
塞直到operation完成。这种方式在有很多Web
Service需要在一个单一的客户端应用程序中启动时很不可取。一种解决方法是使用Non-Blocking API来调用这些Web
Services。Axis2提供给用户一种基于回叫机制的non-blocking API。
EchoNonBlockingClient.java
package userguide.clients;
import org.apache.axiom.om.OMElement;
import
org.apache.axis2.AxisFault;
import
org.apache.axis2.addressing.EndpointReference;
import
org.apache.axis2.client.Options;
import
org.apache.axis2.client.ServiceClient;
import
org.apache.axis2.client.async.AsyncResult;
import
org.apache.axis2.client.async.Callback;
/**
* Sample for asynchronous single channel
non-blocking service invocation.
* Message Exchage Pattern IN-OUT
*/
public
class EchoNonBlockingClient {
private static EndpointReference
targetEPR =
new EndpointReference("
http://127.0.0.1:8080/axis2/services/MyService
");
public static void main(String[] args) {
ServiceClient sender = null;
try {
OMElement
payload = ClientUtil.getEchoOMElement();
Options options =
new Options();
options.setTo(targetEPR);
//Callback to handle the response
Callback callback = new Callback() {
public void onComplete(AsyncResult result) {
System.out.println(result.getResponseEnvelope());
}
public void onError(Exception e) {
e.printStackTrace();
}
};
//Non-Blocking Invocation
sender = new ServiceClient();
sender.setOptions(options);
sender.sendReceiveNonBlocking(payload, callback);
//Wait till the callback receives the response.
while
(!callback.isComplete()) {
Thread.sleep(1000);
}
} catch (AxisFault axisFault) {
axisFault.printStackTrace();
} catch (Exception ex) {
ex.printStackTrace();
} finally {
try {
sender.finalizeInvoke();
} catch (AxisFault axisFault) {
}
}
}
}
结果:
<?xml version='1.0' encoding='utf-8'?>
<soapenv:Envelope
xmlns:soapenv="
http://schemas.xmlsoap.org/soap/envelope/
">
<soapenv:Header />
<soapenv:Body>
<example1:echo
xmlns:example1="
http://example1.org/example1
"
xmlns:tns="
http://ws.apache.org/axis2
">
<example1:Text>
Axis2
Echo String
</example1:Text>
</example1:echo>
</soapenv:Body>
</soapenv:Envelope>
sender.sendReceiveNonBlocking(payload,
callback);这个调用接受一个callback对象作为参数。Axis2客户端API提供了一个抽象类CallBack,其中提供了方法:
public abstract void onComplete(AsyncResult result);
public
abstract void onError(Exception e);
public boolean isComplete() {}
用户需要重写"onComplete " 和 "onError "方法。一旦客户端收到Web
Service的response,onComplete方法将会被调用,这样将中止阻塞状态。
2.5EchoNonBlockingDualClient
当调用的Web
Service需要很长一段时间来完成时,这种由Non-Blocking
API提供的解决方式将有一定的局限性。这种局限性是由使用单一的传输连接来调用Web
Service并接收response造成的。换句话说,客户端提供一种没有阻塞的调用机制,但request和response的传输使用单一的传输
(双工方式)连接(如HTTP)。长时间运行的Web Service调用或Web
Service调用使用单工传输方式(如SMTP)不能简单地利用一个没有阻塞的调用。
一种尝试地解决方法是request和response各自使用单独的传输连接(单工或双工均可)。这种方式产生的问题是如何解决相关性(关联
request和response)。WS-Addressing提供了一种很好的解决方法,在头中使用<wsa:MessageID> 和
<wsa:RelatesTo> 标签。Axis2对这种基于关联机制的寻址方式提供了支持。
用户可以选择Blocking 或Non-Blocking APIs的Web
Service,并使用两个传输连接。通过使用一个布尔标记,同一个API可以调用多个在两个传输连接上的Web Services(IN-OUT
operations)。下例使用Non-Blocking API 以及两个传输连接来实现上文中提到的"echo" operation。
EchoNonBlockingDualClient.java
package userguide.clients;
import org.apache.axiom.om.OMElement;
import
org.apache.axis2.AxisFault;
import org.apache.axis2.Constants;
import
org.apache.axis2.addressing.EndpointReference;
import
org.apache.axis2.client.Options;
import
org.apache.axis2.client.ServiceClient;
import
org.apache.axis2.client.async.AsyncResult;
import
org.apache.axis2.client.async.Callback;
import
javax.xml.namespace.QName;
/**
* Sample for asynchronous dual channel
non-blocking service invocation.
* Message Exchage Pattern IN-OUT
*
Ulitmate asynchronous service invocation sample.
*/
public class
EchoNonBlockingDualClient {
private static EndpointReference
targetEPR =
new EndpointReference("
http://127.0.0.1:8080/axis2/services/MyService
");
public static void main(String[] args) {
ServiceClient sender = null;
try {
OMElement
payload = ClientUtil.getEchoOMElement();
Options options =
new Options();
options.setTo(targetEPR);
options.setTransportInProtocol(Constants.TRANSPORT_HTTP);
options.setUseSeparateListener(true);
options.setAction("urn:echo"); // this is the action mapping we put
within the service.xml
//Callback to handle the response
Callback callback = new Callback() {
public void
onComplete(AsyncResult result) {
System.out.println(result.getResponseEnvelope());
}
public void onError(Exception e) {
e.printStackTrace();
}
};
//Non-Blocking Invocation
ConfigurationContext sysContext
= ConfigurationContextFactory
.createConfigurationContextFromFileSystem(
"D://Dvp//Axis2//axis2//WEB-INF", null);//见注解①
sender =
new ServiceClient(sysContext, null);
sender.engageModule(new QName(Constants.MODULE_ADDRESSING));
sender.setOptions(options);
sender.sendReceiveNonBlocking(payload, callback);
//Wait
till the callback receives the response.
while
(!callback.isComplete()) {
Thread.sleep(1000);
}
//Need to close the Client Side Listener.
}
catch (AxisFault axisFault) {
axisFault.printStackTrace();
} catch (Exception ex) {
ex.printStackTrace();
} finally {
try {
sender.finalizeInvoke();
} catch (AxisFault axisFault) {
//have to ignore
this
}
}
}
}
注
解①
RE: [Axis2] 0.95 WS-Addressing web
SERVICE-SIDE: module not found
I now have managed to get
EchoNonBlockingDualClient working. I still can't get the original code
to work, where ever I put addressing-0.95.mar, but the
ConfigurationContext works.
The code I ended up with was:
ConfigurationContext sysContext =
ConfigurationContextFactory
.createConfigurationContextFromFileSystem(
"C://axis2",
null);
sender = new ServiceClient(sysContext, null);
with no need, obviously, for the .engageModule method.
I did
discover though that the directory which the ConfigurationContext points
to has to have two directories within it: "conf", which must contain
the axis.xml configuration file, and the "modules" directory which
contains addressing-0.95.mar.
在方法"options.setUseSeparateListener(...)"中的布尔标记通知通知Axis2引擎使用两个不同的传输连接来分别处
理request和response。Finally中的
"serviceClient.finalizeInvoke()"方法通知Axis2引擎停用客户端的用于接收response的listener。
在我们运行客户端的例程之前,我们还有一件事情要做。如前面提到的,Axis2使用基于地址的关联机制,因此我们必须在服务器端和客户端“搭建”寻址模
块。
结果:
<?xml version='1.0' encoding='utf-8'?>
<soapenv:Envelope
xmlns:soapenv="
http://schemas.xmlsoap.org/soap/envelope/
" xmlns:wsa="http://www.w3.org/2005/08/addressing
">
<soapenv:Header>
<wsa:To>http://59.14.131.187:6060/axis2/services/__ANONYMOUS_SERVICE__/__OPERATION_OUT_IN__
</wsa:To>
<wsa:ReplyTo>
<wsa:Address>
http://www.w3.org/2005/08/addressing/anonymous
</wsa:Address>
</wsa:ReplyTo>
<wsa:From>
<wsa:Address>
http://127.0.0.1:8080/axis2/services/MyService
</wsa:Address>
</wsa:From>
<wsa:FaultTo>
<wsa:Address>
http://127.0.0.1:8080/axis2/services/MyService
</wsa:Address>
</wsa:FaultTo>
<wsa:MessageID>
urn:uuid:B087CBB98F1B51A24711742241136206
</wsa:MessageID>
<wsa:Action>urn:echo</wsa:Action>
<wsa:RelatesTo
wsa:RelationshipType="wsa:Reply">
urn:uuid:CA4B9513377E6E9E1511742241130391
</wsa:RelatesTo>
</soapenv:Header>
<soapenv:Body>
<example1:echo
xmlns:example1="
http://example1.org/example1
" xmlns:tns="
http://ws.apache.org/axis2
">
<example1:Text>
Axis2
Echo String
</example1:Text>
</example1:echo>
</soapenv:Body>
</soapenv:Envelope>
[SimpleHTTPServer]
Stop called
2.6 实现服务器端的寻址
根据Axis2的结构,寻址模块在"pre-dispatch"阶段已经给出它的句柄。因此,所谓的“搭建”仅仅是在”axis2.xml”(注意不是
services.xml)增加一个模块的引用。现在将下面这行字加入到axis2.xml,该文件在"/webapps/axis2/WEB-INF
/conf"目录下。
<module ref="addressing"/>
注: 一旦你改变了axis2.xml,你必须重启这个servlet容器,改变才能生效。
2.7 实现客户端的寻址
有两种方式。
一种方法是在%Axis2_HOME%/axis2-std-1.0-bin/modules目录下得到
addressing-<version>.mar。并且在你的classpath中对其可见。(此种方法目前,我还没有调试成功,具体见注
解①。下面的第二种方法可用)
另一种方法是创建一个ConfigurationContext,指定一个repository位置。Axis2支持repository的方式来保存服
务和模块。
你可以使用二进制distribution作为repository,只要它含有一个Axis2
repository认可的repository结构(其中应包含services和modules目录)。ConfigurationContext
中含有Axis2体系的运行时的上下文信息。
如果你解压一个标准的二进制distribution到目录(譬如)$user_home/axis2/dist, 那么在 sender = new
ServiceClient();之前加入(具体见EchoNonBlockingDualClient.java):
new
ServiceClient();之前加入(具体见EchoNonBlockingDualClient.java):
ConfigurationContext
configContext =
ConfigurationContextFactory.createConfigurationContextFromFileSystem(<
Axis2RepositoryLocation >, null);
用"sender = new ServiceClient(configContext, null);" 替换 "sender = new
ServiceClient();"
这样可以在客户端和服务器端都实现寻址。
2.8 EchoBlockingDualClient
这又是一个两路的传输的request/response客户端,但这次,我们使用一个Blocking
API。实现机制和EchoNonBlockingDualClient差不多,唯一的不同是,这里不需要使用一个callback对象来处理
response。
EchoBlockingDualClient.java
package userguide.clients;
import org.apache.axiom.om.OMElement;
import
org.apache.axis2.AxisFault;
import org.apache.axis2.Constants;
import
org.apache.axis2.addressing.EndpointReference;
import
org.apache.axis2.client.Options;
import
org.apache.axis2.client.ServiceClient;
import javax.xml.namespace.QName;
import
javax.xml.stream.XMLOutputFactory;
import java.io.StringWriter;
/**
* Sample for synchronous dual channel
blocking service invocation.
* Message Exchage Pattern IN-OUT
*/
public
class EchoBlockingDualClient {
private static EndpointReference
targetEPR =
new EndpointReference("
http://127.0.0.1:8080/axis2/services/MyService
");
public static void main(String[] args) {
ServiceClient sender = null;
try {
OMElement
payload = ClientUtil.getEchoOMElement();
Options options =
new Options();
options.setTo(targetEPR);
options.setAction("urn:echo");
//The boolean flag informs
the axis2 engine to use two separate transport connection
//to retrieve the response.
options.setTransportInProtocol(Constants.TRANSPORT_HTTP);
options.setUseSeparateListener(true);
//Blocking
Invocation
ConfigurationContext sysContext =
ConfigurationContextFactory
.createConfigurationContextFromFileSystem(
"D://Dvp//Axis2//axis2//WEB-INF", null);
sender = new
ServiceClient(sysContext, null);
sender.engageModule(new
QName(Constants.MODULE_ADDRESSING));
sender.setOptions(options);
OMElement result =
sender.sendReceive(payload);
StringWriter writer = new
StringWriter();
result.serialize(XMLOutputFactory.newInstance().createXMLStreamWriter(writer));
writer.flush();
System.out.println(writer.toString());
//Need to close the Client Side Listener.
} catch (AxisFault
axisFault) {
axisFault.printStackTrace();
}
catch (Exception ex) {
ex.printStackTrace();
}
finally{
try {
sender.finalizeInvoke();
} catch (AxisFault axisFault) {
//
}
}
}
}
结果:
<example1:echo
xmlns:example1="
http://example1.org/example1
" xmlns:tns="
http://ws.apache.org/axis2
">
<example1:Text>Axis2
Echo String </example1:Text>
</example1:echo>
[SimpleHTTPServer]
Stop called
1.使用Axis2的底层API开发Web Service Server端
1.1
创建一个WebService(取名为MyService)
在MyService中有两个operations,如下所示。
public void ping(OMElement
element){}//IN-ONLY模式。仅仅接收OMElement,并对其处理。
public OMElement
echo(OMElement element){}//IN_OUT模式。接收OMElemen,并返回OMElement。
1.2如何写Web Service
1)创建实现服务的类。
2)创建services.xml来解析这个Web Service。
3)将其打包成一个*.aar文档(Axis Archive)。
4)部署Web Service。
1.2.1 创建实现服务的类
此类中提供的方法必须与Web
Service(在services.xml中声明)中的operations对应。除非你提供了数据绑定,否则所有的方法只能接收一个参数,其类型为
OMElement。
public class MyService{
public void
ping(OMElement element){...}
public OMElement echo(OMElement
element){...}
}
MyService.java
package userguide.example1;
import org.apache.axiom.om.OMElement;
import
org.apache.axis2.AxisFault;
import
javax.xml.stream.XMLStreamException;
public class MyService {
public OMElement
echo(OMElement element) throws XMLStreamException {
//Praparing the OMElement so that it can be attached to another OM Tree.
//First the OMElement should be completely build in case it is not
fully built and still
//some of the xml is in the stream.
element.build();
//Secondly the OMElement should be detached
from the current OMTree so that it can
// be attached some
other OM Tree. Once detached the OmTree will remove its
//
connections to this OMElement.
element.detach();
return element;
}
public void ping(OMElement element)
throws XMLStreamException {
//Do some processing
}
public void pingF(OMElement element) throws AxisFault{
throw
new AxisFault("Fault being thrown");
}
}
1.2.2 创建services.xml
Axis2使用services.xml来充当一个Web Servicea的配置文件。每一个使用Axis2部署的Web
Service都必须拥有一个services.xml。
<services>
<description>
This is a sample Web Service with two operations,echo and ping.
</description>
<parameter name=”ServiceClass”
locked=”false”>
userguide.example1.MyService
</parameter>
<operation name=”echo”>
<messageReceiver
class=”org.apache.axis2.receivers.RawXMLINOutMessageReceiver”/>
<actionMapping>urn:echo</actionMapping>
</operation>
<operation name=”ping”>
<messageReceiver
class=”org.apache.receivers.RawXMLINOnlyMessageReceiver”/>
<actionMapping>urn:ping</actionMapping>
</operation>
</service>
注:The
actionMapping is required only if you want to enable WS-Addressing.
可以创建一个services.xml,其中包含一组服务。这样在运行期,你可以在这些服务间共享信息。
<serviceGroup>
<service
name=”Service1”>
<!--details for Services1-->
</service>
<service name=”Service2”>
<!--details for Services2-->
</service>
<module
ref=”ModuleName”/>
<parameter name=”serviceGroupParam1”
locked=”false”>value1</parameter>
</serviceGroup>
注:name
of the service is a compulsory attribute.
1.2.3打包与部署
这里不再详述,参见《
基于Tomcat5.0和Axis2开发Web
Service应用实例
》。
2.使用Axis2底层APIs实现Web Service客户端
2.1ClientUtil
创建一个客户端通用的SOAP包装Util文件。封装"getEchoOMElement"和"getPingOMElement"分别对应"echo"
和"ping"这两个operation。
ClientUtil.java
package userguide.clients;
import org.apache.axiom.om.OMAbstractFactory;
import
org.apache.axiom.om.OMElement;
import org.apache.axiom.om.OMFactory;
import
org.apache.axiom.om.OMNamespace;
public class ClientUtil {
public static
OMElement getEchoOMElement() {
OMFactory fac =
OMAbstractFactory.getOMFactory();
OMNamespace omNs =
fac.createOMNamespace(
"
http://example1.org/example1
", "example1");
OMElement method =
fac.createOMElement("echo", omNs);
OMElement value =
fac.createOMElement("Text", omNs);
value.addChild(fac.createOMText(value, "Axis2 Echo String "));
method.addChild(value);
return method;
}
public static OMElement getPingOMElement() {
OMFactory fac =
OMAbstractFactory.getOMFactory();
OMNamespace omNs =
fac.createOMNamespace(
"
http://example1.org/example1
", "example1");
OMElement method =
fac.createOMElement("ping", omNs);
OMElement value =
fac.createOMElement("Text", omNs);
value.addChild(fac.createOMText(value, "Axis2 Ping String "));
method.addChild(value);
return method;
}
}
2.2EchoBlockingClient
Axis2向用户提供了从blocking
single channel调用到non-blocking dual channel调用的多种调用Web
Service的模式。下面用最简单的blocking调用机制来实现”MyService”中的"echo" operation。
EchoBlockingClient.java
package userguide.clients;
import org.apache.axiom.om.OMElement;
import
org.apache.axis2.AxisFault;
import
org.apache.axis2.addressing.EndpointReference;
import
org.apache.axis2.client.Options;
import
org.apache.axis2.client.ServiceClient;
/**
* Sample for synchronous single channel
blocking service invocation.
* Message Exchage Pattern IN-OUT
*/
public
class EchoBlockingClient {
private static EndpointReference
targetEPR =
new EndpointReference("
http://localhost:8080/axis2/services/MyService
");
public static void main(String[] args) {
try {
OMElement payload = ClientUtil.getEchoOMElement();
Options options = new Options();
options.setTo(targetEPR); // this sets the location of MyService
service
ServiceClient serviceClient = new
ServiceClient();
serviceClient.setOptions(options);
OMElement result = sender.sendReceive(payload);
System.out.println(result);
} catch (AxisFault axisFault) {
axisFault.printStackTrace();
}
}
绿色部分显示了为了调用一个Web
Service而需要对operation作的设置。剩下的部分是用来创建OMElement,用来发送和显示相应的OMElement。
结果:
<example1:echo xmlns:example1="
http://example1.org/example1
"
xmlns:tns="
http://ws.apache.org/axis2
">
<example1:Text>
Axis2
Echo String
</example1:Text>
</example1:echo>
2.3 PingClient
在”MyService”中,我们有一种IN-ONLY模式的名为"ping"的operation。应用它的客户端代码如下:
PingClient.java
package userguide.clients;
import org.apache.axiom.om.OMElement;
import
org.apache.axis2.AxisFault;
import
org.apache.axis2.addressing.EndpointReference;
import
org.apache.axis2.client.Options;
import
org.apache.axis2.client.ServiceClient;
/**
* Sample for fire-and-forget service
invocation
* Message Exchage Pattern IN-Only
*/
public class
PingClient {
private static EndpointReference targetEPR =
new
EndpointReference("
http://localhost:8080/axis2/services/MyService
");
public static void main(String[] args) {
try {
OMElement payload = ClientUtil.getPingOMElement();
Options
options = new Options();
options.setTo(targetEPR);
ServiceClient serviceClient = new ServiceClient();
serviceClient.setOptions(options);
serviceClient.fireAndForget(payload);
/**
* We have to block this thread untill we send the
request , the problem
* is if we go out of the main thread ,
then request wont send ,so
* you have to wait some time :)
*/
Thread.sleep(500);
}
catch (AxisFault
axisFault) {
axisFault.printStackTrace();
}
}
由于我们在访问一个IN-ONLY模式的operation,所以我们可以直接使用ServiceClient中的"fireAndForget()"方
法来调用这个operation。而且那样做的话,不会阻塞发起端,因此,它会立刻将控制权返回给客户端。
2.4 EchoNonBlockingClient
在客户端EchoBlockingClient,一旦调用"serviceClient.sendReceive(payload);",客户端将会被阻
塞直到operation完成。这种方式在有很多Web
Service需要在一个单一的客户端应用程序中启动时很不可取。一种解决方法是使用Non-Blocking API来调用这些Web
Services。Axis2提供给用户一种基于回叫机制的non-blocking API。
EchoNonBlockingClient.java
package userguide.clients;
import org.apache.axiom.om.OMElement;
import
org.apache.axis2.AxisFault;
import
org.apache.axis2.addressing.EndpointReference;
import
org.apache.axis2.client.Options;
import
org.apache.axis2.client.ServiceClient;
import
org.apache.axis2.client.async.AsyncResult;
import
org.apache.axis2.client.async.Callback;
/**
* Sample for asynchronous single channel
non-blocking service invocation.
* Message Exchage Pattern IN-OUT
*/
public
class EchoNonBlockingClient {
private static EndpointReference
targetEPR =
new EndpointReference("
http://127.0.0.1:8080/axis2/services/MyService
");
public static void main(String[] args) {
ServiceClient sender = null;
try {
OMElement
payload = ClientUtil.getEchoOMElement();
Options options =
new Options();
options.setTo(targetEPR);
//Callback to handle the response
Callback callback = new Callback() {
public void onComplete(AsyncResult result) {
System.out.println(result.getResponseEnvelope());
}
public void onError(Exception e) {
e.printStackTrace();
}
};
//Non-Blocking Invocation
sender = new ServiceClient();
sender.setOptions(options);
sender.sendReceiveNonBlocking(payload, callback);
//Wait till the callback receives the response.
while
(!callback.isComplete()) {
Thread.sleep(1000);
}
} catch (AxisFault axisFault) {
axisFault.printStackTrace();
} catch (Exception ex) {
ex.printStackTrace();
} finally {
try {
sender.finalizeInvoke();
} catch (AxisFault axisFault) {
}
}
}
}
结果:
<?xml version='1.0' encoding='utf-8'?>
<soapenv:Envelope
xmlns:soapenv="
http://schemas.xmlsoap.org/soap/envelope/
">
<soapenv:Header />
<soapenv:Body>
<example1:echo
xmlns:example1="
http://example1.org/example1
"
xmlns:tns="
http://ws.apache.org/axis2
">
<example1:Text>
Axis2
Echo String
</example1:Text>
</example1:echo>
</soapenv:Body>
</soapenv:Envelope>
sender.sendReceiveNonBlocking(payload,
callback);这个调用接受一个callback对象作为参数。Axis2客户端API提供了一个抽象类CallBack,其中提供了方法:
public abstract void onComplete(AsyncResult result);
public
abstract void onError(Exception e);
public boolean isComplete() {}
用户需要重写"onComplete " 和 "onError "方法。一旦客户端收到Web
Service的response,onComplete方法将会被调用,这样将中止阻塞状态。
2.5EchoNonBlockingDualClient
当调用的Web
Service需要很长一段时间来完成时,这种由Non-Blocking
API提供的解决方式将有一定的局限性。这种局限性是由使用单一的传输连接来调用Web
Service并接收response造成的。换句话说,客户端提供一种没有阻塞的调用机制,但request和response的传输使用单一的传输
(双工方式)连接(如HTTP)。长时间运行的Web Service调用或Web
Service调用使用单工传输方式(如SMTP)不能简单地利用一个没有阻塞的调用。
一种尝试地解决方法是request和response各自使用单独的传输连接(单工或双工均可)。这种方式产生的问题是如何解决相关性(关联
request和response)。WS-Addressing提供了一种很好的解决方法,在头中使用<wsa:MessageID> 和
<wsa:RelatesTo> 标签。Axis2对这种基于关联机制的寻址方式提供了支持。
用户可以选择Blocking 或Non-Blocking APIs的Web
Service,并使用两个传输连接。通过使用一个布尔标记,同一个API可以调用多个在两个传输连接上的Web Services(IN-OUT
operations)。下例使用Non-Blocking API 以及两个传输连接来实现上文中提到的"echo" operation。
EchoNonBlockingDualClient.java
package userguide.clients;
import org.apache.axiom.om.OMElement;
import
org.apache.axis2.AxisFault;
import org.apache.axis2.Constants;
import
org.apache.axis2.addressing.EndpointReference;
import
org.apache.axis2.client.Options;
import
org.apache.axis2.client.ServiceClient;
import
org.apache.axis2.client.async.AsyncResult;
import
org.apache.axis2.client.async.Callback;
import
javax.xml.namespace.QName;
/**
* Sample for asynchronous dual channel
non-blocking service invocation.
* Message Exchage Pattern IN-OUT
*
Ulitmate asynchronous service invocation sample.
*/
public class
EchoNonBlockingDualClient {
private static EndpointReference
targetEPR =
new EndpointReference("
http://127.0.0.1:8080/axis2/services/MyService
");
public static void main(String[] args) {
ServiceClient sender = null;
try {
OMElement
payload = ClientUtil.getEchoOMElement();
Options options =
new Options();
options.setTo(targetEPR);
options.setTransportInProtocol(Constants.TRANSPORT_HTTP);
options.setUseSeparateListener(true);
options.setAction("urn:echo"); // this is the action mapping we put
within the service.xml
//Callback to handle the response
Callback callback = new Callback() {
public void
onComplete(AsyncResult result) {
System.out.println(result.getResponseEnvelope());
}
public void onError(Exception e) {
e.printStackTrace();
}
};
//Non-Blocking Invocation
ConfigurationContext sysContext
= ConfigurationContextFactory
.createConfigurationContextFromFileSystem(
"D://Dvp//Axis2//axis2//WEB-INF", null);//见注解①
sender =
new ServiceClient(sysContext, null);
sender.engageModule(new QName(Constants.MODULE_ADDRESSING));
sender.setOptions(options);
sender.sendReceiveNonBlocking(payload, callback);
//Wait
till the callback receives the response.
while
(!callback.isComplete()) {
Thread.sleep(1000);
}
//Need to close the Client Side Listener.
}
catch (AxisFault axisFault) {
axisFault.printStackTrace();
} catch (Exception ex) {
ex.printStackTrace();
} finally {
try {
sender.finalizeInvoke();
} catch (AxisFault axisFault) {
//have to ignore
this
}
}
}
}
注
解①
RE: [Axis2] 0.95 WS-Addressing web
SERVICE-SIDE: module not found
I now have managed to get
EchoNonBlockingDualClient working. I still can't get the original code
to work, where ever I put addressing-0.95.mar, but the
ConfigurationContext works.
The code I ended up with was:
ConfigurationContext sysContext =
ConfigurationContextFactory
.createConfigurationContextFromFileSystem(
"C://axis2",
null);
sender = new ServiceClient(sysContext, null);
with no need, obviously, for the .engageModule method.
I did
discover though that the directory which the ConfigurationContext points
to has to have two directories within it: "conf", which must contain
the axis.xml configuration file, and the "modules" directory which
contains addressing-0.95.mar.
在方法"options.setUseSeparateListener(...)"中的布尔标记通知通知Axis2引擎使用两个不同的传输连接来分别处
理request和response。Finally中的
"serviceClient.finalizeInvoke()"方法通知Axis2引擎停用客户端的用于接收response的listener。
在我们运行客户端的例程之前,我们还有一件事情要做。如前面提到的,Axis2使用基于地址的关联机制,因此我们必须在服务器端和客户端“搭建”寻址模
块。
结果:
<?xml version='1.0' encoding='utf-8'?>
<soapenv:Envelope
xmlns:soapenv="
http://schemas.xmlsoap.org/soap/envelope/
" xmlns:wsa="http://www.w3.org/2005/08/addressing
">
<soapenv:Header>
<wsa:To>http://59.14.131.187:6060/axis2/services/__ANONYMOUS_SERVICE__/__OPERATION_OUT_IN__
</wsa:To>
<wsa:ReplyTo>
<wsa:Address>
http://www.w3.org/2005/08/addressing/anonymous
</wsa:Address>
</wsa:ReplyTo>
<wsa:From>
<wsa:Address>
http://127.0.0.1:8080/axis2/services/MyService
</wsa:Address>
</wsa:From>
<wsa:FaultTo>
<wsa:Address>
http://127.0.0.1:8080/axis2/services/MyService
</wsa:Address>
</wsa:FaultTo>
<wsa:MessageID>
urn:uuid:B087CBB98F1B51A24711742241136206
</wsa:MessageID>
<wsa:Action>urn:echo</wsa:Action>
<wsa:RelatesTo
wsa:RelationshipType="wsa:Reply">
urn:uuid:CA4B9513377E6E9E1511742241130391
</wsa:RelatesTo>
</soapenv:Header>
<soapenv:Body>
<example1:echo
xmlns:example1="
http://example1.org/example1
" xmlns:tns="
http://ws.apache.org/axis2
">
<example1:Text>
Axis2
Echo String
</example1:Text>
</example1:echo>
</soapenv:Body>
</soapenv:Envelope>
[SimpleHTTPServer]
Stop called
2.6 实现服务器端的寻址
根据Axis2的结构,寻址模块在"pre-dispatch"阶段已经给出它的句柄。因此,所谓的“搭建”仅仅是在”axis2.xml”(注意不是
services.xml)增加一个模块的引用。现在将下面这行字加入到axis2.xml,该文件在"/webapps/axis2/WEB-INF
/conf"目录下。
<module ref="addressing"/>
注: 一旦你改变了axis2.xml,你必须重启这个servlet容器,改变才能生效。
2.7 实现客户端的寻址
有两种方式。
一种方法是在%Axis2_HOME%/axis2-std-1.0-bin/modules目录下得到
addressing-<version>.mar。并且在你的classpath中对其可见。(此种方法目前,我还没有调试成功,具体见注
解①。下面的第二种方法可用)
另一种方法是创建一个ConfigurationContext,指定一个repository位置。Axis2支持repository的方式来保存服
务和模块。
你可以使用二进制distribution作为repository,只要它含有一个Axis2
repository认可的repository结构(其中应包含services和modules目录)。ConfigurationContext
中含有Axis2体系的运行时的上下文信息。
如果你解压一个标准的二进制distribution到目录(譬如)$user_home/axis2/dist, 那么在 sender = new
ServiceClient();之前加入(具体见EchoNonBlockingDualClient.java):
new
ServiceClient();之前加入(具体见EchoNonBlockingDualClient.java):
ConfigurationContext
configContext =
ConfigurationContextFactory.createConfigurationContextFromFileSystem(<
Axis2RepositoryLocation >, null);
用"sender = new ServiceClient(configContext, null);" 替换 "sender = new
ServiceClient();"
这样可以在客户端和服务器端都实现寻址。
2.8 EchoBlockingDualClient
这又是一个两路的传输的request/response客户端,但这次,我们使用一个Blocking
API。实现机制和EchoNonBlockingDualClient差不多,唯一的不同是,这里不需要使用一个callback对象来处理
response。
EchoBlockingDualClient.java
package userguide.clients;
import org.apache.axiom.om.OMElement;
import
org.apache.axis2.AxisFault;
import org.apache.axis2.Constants;
import
org.apache.axis2.addressing.EndpointReference;
import
org.apache.axis2.client.Options;
import
org.apache.axis2.client.ServiceClient;
import javax.xml.namespace.QName;
import
javax.xml.stream.XMLOutputFactory;
import java.io.StringWriter;
/**
* Sample for synchronous dual channel
blocking service invocation.
* Message Exchage Pattern IN-OUT
*/
public
class EchoBlockingDualClient {
private static EndpointReference
targetEPR =
new EndpointReference("
http://127.0.0.1:8080/axis2/services/MyService
");
public static void main(String[] args) {
ServiceClient sender = null;
try {
OMElement
payload = ClientUtil.getEchoOMElement();
Options options =
new Options();
options.setTo(targetEPR);
options.setAction("urn:echo");
//The boolean flag informs
the axis2 engine to use two separate transport connection
//to retrieve the response.
options.setTransportInProtocol(Constants.TRANSPORT_HTTP);
options.setUseSeparateListener(true);
//Blocking
Invocation
ConfigurationContext sysContext =
ConfigurationContextFactory
.createConfigurationContextFromFileSystem(
"D://Dvp//Axis2//axis2//WEB-INF", null);
sender = new
ServiceClient(sysContext, null);
sender.engageModule(new
QName(Constants.MODULE_ADDRESSING));
sender.setOptions(options);
OMElement result =
sender.sendReceive(payload);
StringWriter writer = new
StringWriter();
result.serialize(XMLOutputFactory.newInstance().createXMLStreamWriter(writer));
writer.flush();
System.out.println(writer.toString());
//Need to close the Client Side Listener.
} catch (AxisFault
axisFault) {
axisFault.printStackTrace();
}
catch (Exception ex) {
ex.printStackTrace();
}
finally{
try {
sender.finalizeInvoke();
} catch (AxisFault axisFault) {
//
}
}
}
}
结果:
<example1:echo
xmlns:example1="
http://example1.org/example1
" xmlns:tns="
http://ws.apache.org/axis2
">
<example1:Text>Axis2
Echo String </example1:Text>
</example1:echo>
[SimpleHTTPServer]
Stop called
相关文章推荐
- 使用Axis2的底层API开发Web Service
- 使用Axis2的底层API开发Web Service
- 使用Axis2的底层API开发Web Service
- 使用Axis2的底层API开发Web Service
- 使用Axis2的底层API开发Web Service Server端
- 使用Axis2开发Web Service简单演示实例
- 使用 Axis2主要API开发WebService客户端
- 使用Axis2开发Web Service简单演示实例
- arcgis api for flex 开发入门(九)webservices 的使用
- 图解使用Win8Api进行Metro风格的程序开发八----剪贴板
- ArcGIS API for javascript开发笔记(六)——REST详解及如何使用REST API调用GP服务
- 安卓开发中,在低版本SDK使用高版本的API会报错。一般处理方法是换一种实现方法,或者在高版本SDK中使用高版本API,低版本SDK中使用效果可能会差点的折衷方案;后者可以用如下技巧来实现。
- 使用C#开发HTTP服务器系列之构建RESTful API
- 使用CXF开发web service 的服务器端(三)
- JAVA使用XFire开发Web Service客户端几种调用方式
- WebService从零到项目开发使用3—技术研究之Axis2 POJO开发Web服务
- ArcGIS API for Silverlight开发入门(7):使用非AGS数据源的图层
- 转:使用 python 开发 Web Service
- 速动画教程第二十五集 使用 xfire 开发 web service 应用
- 使用MSN Search Web Service开发搜索应用