Android学习笔记（十二）-WebService调用

在J2EE项目中，我们可以根据WSDL通过各种框架来直接生成WebService的客户端调用代码，在Android中，也有第三方的框架可用于调用WebService，这里介绍一种通过使用HTTP协议来模拟WebService调用过程的方法，即自己根据规范来构建请求的XML，然后通过HTTP协议发送，最后自己解析响应的XML。

这里以一个获得国内手机号码归属地数据库信息的WebService为例：

http://webservice.webxml.com.cn/WebServices/MobileCodeWS.asmx

SSOAP 1.2

以下是 SOAP 1.2 请求和响应示例。所显示的占位符需替换为实际值。

POST /WebServices/MobileCodeWS.asmx HTTP/1.1Host: webservice.webxml.com.cnContent-Type: application/soap+xml; charset=utf-8Content-Length: length<?xml version="1.0" encoding="utf-8"?><soap12:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap12="http://www.w3.org/2003/05/soap-envelope">  <soap12:Body>    <getMobileCodeInfo xmlns="http://WebXml.com.cn/">      <mobileCode>string</mobileCode>      <userID>string</userID>    </getMobileCodeInfo>  </soap12:Body></soap12:Envelope>
HTTP/1.1 200 OKContent-Type: application/soap+xml; charset=utf-8Content-Length: length<?xml version="1.0" encoding="utf-8"?><soap12:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap12="http://www.w3.org/2003/05/soap-envelope">  <soap12:Body>    <getMobileCodeInfoResponse xmlns="http://WebXml.com.cn/">      <getMobileCodeInfoResult>string</getMobileCodeInfoResult>    </getMobileCodeInfoResponse>  </soap12:Body></soap12:Envelope>

首先是要构建请求的XML，可以采用Pull方式来构建，这里采用正则表达式的方式来替换字符串，这样更简单一些。

在src下建立一个mobilesoap.xml文件

<?xml version="1.0" encoding="utf-8"?><soap12:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap12="http://www.w3.org/2003/05/soap-envelope">  <soap12:Body>    <getMobileCodeInfo xmlns="http://WebXml.com.cn/">      <mobileCode>$mobile</mobileCode>      <userID></userID>    </getMobileCodeInfo>  </soap12:Body></soap12:Envelope>

使用正则表达式将$mobile替换成实际的手机号即可。

至于返回的XML可以使用Pull方式来解析。

项目运行效果如下：

布局文件：layout/main.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:orientation="vertical" >    <TextView        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="@string/mobile" />    <EditText        android:id="@+id/mobile"        android:layout_width="fill_parent"        android:layout_height="wrap_content" />    <Button        android:id="@+id/button"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="@string/button" />    <TextView        android:id="@+id/address"        android:layout_width="fill_parent"        android:layout_height="wrap_content" /></LinearLayout>

数据文件：values/strings.xml

<?xml version="1.0" encoding="utf-8"?><resources>    <string name="hello">Hello World, MobileAddressActivity!</string>    <string name="app_name">手机号归属地查询</string>    <string name="mobile">手机号</string>    <string name="button">查询</string></resources>

MobileAddressActivity.java

package com.android.ws;import java.io.InputStream;import android.app.Activity;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.Button;import android.widget.EditText;import android.widget.TextView;import android.widget.Toast;import com.android.service.MobileService;public class MobileAddressActivity extends Activity {private EditText mobileText;    private TextView addressView;    private static final String TAG = "MainActivity";    /** Called when the activity is first created. */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);                mobileText = (EditText)this.findViewById(R.id.mobile);        addressView = (TextView)this.findViewById(R.id.address);        Button button = (Button)this.findViewById(R.id.button);        button.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {String mobile = mobileText.getText().toString();InputStream inStream = this.getClass().getClassLoader().getResourceAsStream("mobilesoap.xml");try {addressView.setText(MobileService.getMobileAddress(inStream, mobile));} catch (Exception e) {Log.e(TAG, e.toString());e.printStackTrace();Toast.makeText(MobileAddressActivity.this, "查询失败", 1).show();}}});    }}

MobileService.java

package com.android.service;import java.io.InputStream;import java.io.OutputStream;import java.net.HttpURLConnection;import java.net.URL;import java.util.HashMap;import java.util.Map;import java.util.regex.Matcher;import java.util.regex.Pattern;import org.xmlpull.v1.XmlPullParser;import android.util.Xml;import com.android.utils.StreamTool;public class MobileService {private static String readSoapFile(InputStream inStream, String mobile) throws Exception{byte[] data = StreamTool.readInputStream(inStream);String soapxml = new String(data);Map<String, String> params = new HashMap<String, String>();params.put("mobile", mobile);return replace(soapxml, params);}public static String replace(String xml, Map<String, String> params)throws Exception{String result = xml;if(params!=null && !params.isEmpty()){for(Map.Entry<String, String> entry : params.entrySet()){String name = "\\{1}quot;+ entry.getKey();Pattern pattern = Pattern.compile(name);Matcher matcher = pattern.matcher(result);if(matcher.find()){result = matcher.replaceAll(entry.getValue());}}}return result;}public static String getMobileAddress(InputStream inStream, String mobile)throws Exception{String soap = readSoapFile(inStream, mobile);byte[] data = soap.getBytes();URL url = new URL("http://webservice.webxml.com.cn/WebServices/MobileCodeWS.asmx");HttpURLConnection conn = (HttpURLConnection)url.openConnection();conn.setRequestMethod("POST");conn.setConnectTimeout(5 * 1000);conn.setDoOutput(true);//如果通过post提交数据，必须设置允许对外输出数据conn.setRequestProperty("Content-Type", "application/soap+xml; charset=utf-8");conn.setRequestProperty("Content-Length", String.valueOf(data.length));OutputStream outStream = conn.getOutputStream();outStream.write(data);outStream.flush();outStream.close();if(conn.getResponseCode()==200){return parseResponseXML(conn.getInputStream());}return null;}private static String parseResponseXML(InputStream inStream) throws Exception{XmlPullParser parser = Xml.newPullParser();parser.setInput(inStream, "UTF-8");int eventType = parser.getEventType();//产生第一个事件while(eventType != XmlPullParser.END_DOCUMENT){//只要不是文档结束事件switch (eventType) {case XmlPullParser.START_TAG:String name = parser.getName();//获取解析器当前指向的元素的名称if("getMobileCodeInfoResult".equals(name)){return parser.nextText();}break;}eventType = parser.next();}return null;}}

StreamTool.java

package com.android.utils;import java.io.ByteArrayOutputStream;import java.io.InputStream;public class StreamTool {/** * 从输入流中读取数据 * @param is 输入流 * @return * @throws Exception */public static byte[] readInputStream(InputStream is) throws Exception{ByteArrayOutputStream baos = new ByteArrayOutputStream();byte[] buf = new byte[1024];int len = 0;while((len = is.read(buf)) != -1){baos.write(buf, 0, len);}baos.flush();baos.close();return baos.toByteArray();}}

另外需要在AndroidManifest.xml中添加网络访问权限：

<!-- 访问网络的权限 -->
<uses-permission android:name="android.permission.INTERNET"/>