J2ME与Web Service-KSOAP的迅速上手

1、服务端

这次要发布的web service非常简单。它的功能是把从客户端传入的字符串中的小写字母转变成大写字母，再返回给客户端。

Soap 服务器采用apache的AXIS（可以从http://ws.apache.org/axis/下载），应用服务器可以选用各种servlet 容器，我这里采用的是weblogic。

1.1 实现类的源代码：


// StringProcessor.java
package com.jagie.j2me.ws;

public class StringProcessor
{
  public StringProcessor()
  {
  }

  public String process(String name)
  {
    return name.toUpperCase();
  }

}

1.2 发布步骤

1．准备一个目录作为web application的发布目录,我这里的这个目录叫jagiews,这个目录的全路径中最好不要有空格和中文。我的发布目录结构如下：

2．编译StringProcessor.java,把生成的StringProcessor.class置于: \jagiews\WEB-INF\classes\com\jagie\j2me\ws目录下。

3.在jagiews\WEB-INF\lib 文件夹中置入以下axis服务器需要的jar文件 axis.jar，axis-ant.jar，commons-discovery.jar，commons-logging.jar，jaxrpc.jar，log4j-1.2.8.jar，saaj.jar ，wsdl4j.jar。这些文件可以在http://ws.apache.org/axis/下载。

4.在jagiews\WEB-INF目录下增加2个发布描述文件：
server-config.wsdd，web.xml。
#server-config.wsdd

<?xml version="1.0" encoding="UTF-8"?>
<deployment xmlns=
"http://xml.apache.org/axis/wsdd/"
xmlns:java=
"http://xml.apache.org/axis/wsdd/providers/java">
<globalConfiguration>
  <parameter name=
  "adminPassword" value="admin"/>
  <parameter name=
  "attachments.Directory"
  value="C:\Program Files
  \Apache Tomcat 4.0\webapps
  \axis\WEB-INF\attachments"/>
  <parameter name=
  "attachments.implementation"
  value="org.apache.axis.
  attachments.AttachmentsImpl"/>
  <parameter name=
  "sendXsiTypes"
  value="true"/>
  <parameter name=
  "sendMultiRefs"
  value="true"/>
  <parameter name=
  "sendXMLDeclaration"
  value="true"/>
  <parameter name=
  "axis.sendMinimizedElements"
  value="true"/>
  <requestFlow>
   <handler type=
   "java:org.apache.axis.handlers.JWSHandler">
    <parameter
name="scope"
value="session"/>
   </handler>
   <handler type=
   "java:org.apache.axis.handlers.JWSHandler">
    <parameter
name="scope"
value="request"/>
    <parameter
name="extension"
value=".jwr"/>
   </handler>
  </requestFlow>
</globalConfiguration>
<handler name=
"LocalResponder"
type="java:org.apache.axis.
transport.local.LocalResponder"/>
<handler name="URLMapper"
type="java:org.apache.axis.
handlers.http.URLMapper"/>
<handler name="RPCDispatcher"
type="java:org.apache.axis.
providers.java.RPCProvider"/>
<handler name="Authenticate"
type="java:org.apache.axis.
handlers.SimpleAuthenticationHandler"/>
<handler name="MsgDispatcher"
type="java:org.apache.axis.
providers.java.MsgProvider"/>

<service name="AdminService"
provider="java:MSG">
  <parameter name="allowedMethods"
  value="AdminService"/>
  <parameter name="enableRemoteAdmin"
  value="false"/>
  <parameter name="className"
  value="org.apache.axis.utils.Admin"/>
  <namespace>
  http://xml.apache.org/axis/wsdd/
  </namespace>
</service>
<service name="Version"
provider="java:RPC">
  <parameter name="allowedMethods"
  value="getVersion"/>
  <parameter name="className"
  value="org.apache.axis.Version"/>
</service>
<!--  your service  begin-->
  <service name="StringProcess"
  provider="java:RPC">
  <parameter name="allowedMethods"
  value="process"/>
  <parameter name="className"
  value="com.jagie.j2me.
  ws.StringProcessor"/>
</service>
<!-- your service  end -->
<transport name="http">
  <requestFlow>
   <handler type="URLMapper"/>
   <handler type=
   "java:org.apache.axis.handlers.
   http.HTTPAuthHandler"/>
  </requestFlow>
</transport>
<transport name="local">
  <responseFlow>
   <handler type="java:org.apache.axis.
   transport.local.LocalResponder"/>
  </responseFlow>
</transport>
</deployment>

# web.xml

<?xml version="1.0"
encoding="ISO-8859-1"?>

<!DOCTYPE web-app
    PUBLIC "-//Sun Microsystems,
Inc.//DTD Web Application 2.3//EN"
    "http://java.sun.com
/j2ee/dtds/web-app_2.2.dtd">

<web-app>
  <display-name>Apache-Axis</display-name>
  <servlet>
    <servlet-name>AxisServlet</servlet-name>
    <display-name>Apache-Axis
Servlet</display-name>
    <servlet-class>
        org.apache.axis.transport.http.AxisServlet
    </servlet-class>
  </servlet>

  <servlet>
    <servlet-name>AdminServlet</servlet-name>
    <display-name>Axis Admin Servlet</display-name>
    <servlet-class>
        org.apache.axis.transport.http.AdminServlet
    </servlet-class>
    <load-on-startup>100</load-on-startup>
  </servlet>

  <servlet>
    <servlet-name>SOAPMonitorService</servlet-name>
    <display-name>SOAPMonitorService</display-name>
    <servlet-class>
        org.apache.axis.monitor.SOAPMonitorService
    </servlet-class>
    <init-param>
      <param-name>SOAPMonitorPort</param-name>
      <param-value>5001</param-value>
    </init-param>
    <load-on-startup>100</load-on-startup>
  </servlet>

  <servlet-mapping>
    <servlet-name>AxisServlet</servlet-name>
    <url-pattern>/servlet/AxisServlet</url-pattern>
  </servlet-mapping>

  <servlet-mapping>
    <servlet-name>AxisServlet</servlet-name>
    <url-pattern>*.jws</url-pattern>
  </servlet-mapping>

  <servlet-mapping>
    <servlet-name>AxisServlet</servlet-name>
    <url-pattern>/services/*</url-pattern>
  </servlet-mapping>

  <servlet-mapping>
    <servlet-name>SOAPMonitorService</servlet-name>
    <url-pattern>/SOAPMonitor</url-pattern>
  </servlet-mapping>

<!-- uncomment this if you want the admin servlet -->
<!--
  <servlet-mapping>
    <servlet-name>AdminServlet</servlet-name>
    <url-pattern>/servlet/AdminServlet
</url-pattern>
  </servlet-mapping>
-->

    <!-- currently the W3C havent settled
on a media type for WSDL;
    http://www.w3.org/TR/2003/
WD-wsdl12-20030303/#ietf-draft
    for now we go with the basic
''it''s XML'' response -->
  <mime-mapping>
    <extension>wsdl</extension>
     <mime-type>text/xml</mime-type>
  </mime-mapping>
  <mime-mapping>
    <extension>xsd</extension>
    <mime-type>text/xml</mime-type>
  </mime-mapping>
</web-app>




5.开启你的application server，把目录jagiews发布为一个名叫jagiews的web application。

6.测试:打开浏览器，输入网址（这里使用的是weblogic,其他的服务器请酌情修改）: http://localhost:7001/jagiews/services/StringProcess?method=process&name=qqqq，如果浏览器能在返回的xml文档中显示字符串"QQQQ"，恭喜你，你的web service发布成功了。如果发布不成功，请按以上发布步骤检查一下。

2、客户端

客户端自然是用MIDlet了，不过用什么方式来访问web service呢？其实有3种访问方式

直接用HttpConnection访问 http://localhost:7001/jagiews/services/StringProcess?method=process&name=qqqq，得到xml的返回数据，然后用kxml(http://kxml.enhydra.org/)解析，得到返回值。

如果你的手机支持MIDP2.0的话，可以考虑使用JSR172。

用ksoap api。

这里讲述第三种方式。使用之前，你需要从 http://ksoap.enhydra.org/software/downloads/index.html下载稳定的ksoap包，置于你的classpath中。

2.1 客户端源代码

2.1.1 WSClientMIDlet.java


package com.jagie.j2me.ws;

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

/**
* <p>Title: </p>
* <p>Description: </p>
* <p>Copyright: Copyright (c)
2004</p>
* <p>Company: </p>
* @author not attributable
* @version 1.0
*/

public class WSClientMIDlet
    extends MIDlet
{
  static WSClientMIDlet instance;

  public WSClientMIDlet()
  {
    instance = this;
  }

  public void startApp()
  {
    Display display=
Display.getDisplay(this);
    DisplayForm displayable =
new DisplayForm();
    display.setCurrent(displayable);

  }

  public void pauseApp()
  {
  }

  public void destroyApp
  (boolean unconditional)
  {
  }

  public static void quitApp()
  {
    instance.destroyApp(true);
    instance.notifyDestroyed();
    instance = null;
  }

}




2.1.2 DisplayForm.java


package com.jagie.j2me.ws;
import javax.microedition.lcdui.*;
/**
* <p>Title: </p>
* <p>Description: </p>
* <p>Copyright: Copyright (c)
2004</p>
* <p>Company: </p>
* @author not attributable
* @version 1.0
*/

public class DisplayForm
    extends Form
    implements CommandListener,
Runnable
{
  private TextField textField1;
  private Thread t;

  public DisplayForm()
  {
    super("字符转换webservice测试");

    try
{
      jbInit();
    }
    catch (Exception e)
{
      e.printStackTrace();
    }


  }

  private void jbInit()
  throws Exception
  {
    // Set up this Displayable
to listen to command events
    textField1 = new TextField
("", "", 15, TextField.ANY);
    this.setCommandListener(this);
    textField1.setLabel
("待处理的字符串是：");
    textField1.setConstraints
(TextField.ANY);
    textField1.setInitialInputMode
("Tester");
    setCommandListener(this);
    // add the Exit command
    addCommand(new Command
("Exit", Command.EXIT, 1));
    addCommand(new Command
("Process", Command.OK, 1));
    this.append(textField1);
  }

  public void commandAction
  (Command command,
  Displayable displayable)
  {

    if (command.getCommandType
() == Command.EXIT)
{
      WSClientMIDlet.quitApp();
    }
    else if (command.getCommandType()
== Command.OK)
{
      t = new Thread(this);
      t.start();
    }
  }

  public void run()
  {
    String s1 =
textField1.getString();
    String s2 =
new StringProcessorStub().process(s1);
    StringItem resultItem =
new StringItem("处理后的字符串是:", s2);
    this.append(resultItem);
}
}




2.1.3 StringProcessorStub.java


package com.jagie.j2me.ws;

import org.ksoap.*;
import org.ksoap.transport.HttpTransport;

/**
* <p>Title: </p>
* <p>Description: </p>
* <p>Copyright: Copyright (c) 2004</p>
* <p>Company: </p>
* @author not attributable
* @version 1.0
*/

  public class StringProcessorStub
  {
    public StringProcessorStub()
{
  }

  public String process(String name)
  {
    String result = null;
    try
{

      SoapObject rpc =
   new SoapObject
    ("http://localhost:
7001/jagiews/services/StringProcess",
"process");

      rpc.addProperty("name", name);

      HttpTransport ht =
   new HttpTransport
    ("http://localhost:7001/
jagiews/services/StringProcess",
"");

      result = (String) ht.call(rpc);

    }
    catch (Exception e) {
      e.printStackTrace();
    }

    return result;

  }
}


总结

有了ksoap，手机上调用web service就很容易了。不过要注意的是，使用网络连接这种费时操作的时候，一定要单独开线程进行，不要直接写在commandAction()方法里，否则出现画面被锁住的情况。

……