在企业开发领域，webservice还是经常被用到的服务体系，因为他对安全事务支持都比较好。

有时候，我们就需要在android下调用后端的webservice服务，因为在内部网络环境下，所有需要basic身份验证。

一般情况下，我们会用soap包来访问，但是soap包虽然封装的比较好，但是一旦出错很难找到原因。下面我们介绍一种简单的方式，通过http client post来访问webservice;

首先，我们把soap请求拼装成xml字符串，如下：

String soapRequestData = "<?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>"

	+ " <GetAPACShippingPackage xmlns=\"xx/\">"

	+ " <GetAPACShippingPackageRequest>"

	+ " <TrackCode>123</TrackCode>"

	+ " <Version>123</Version>"

	+ " <APIDevUserID>123</APIDevUserID>"

	+ " <APIPassword>123</APIPassword>"

	+ " <APISellerUserID>123</APISellerUserID>"

	+ " <MessageID>123</MessageID>"

	+ " </GetAPACShippingPackageRequest>"

	+ " </GetAPACShippingPackage>" + "</soap12:Body>"

	+ " </soap12:Envelope>";

创建postMethod:

PostMethod postMethod = new PostMethod(

                "http://xx?wsdl");

声明他是一个soap请求：

StringRequestEntity requestEntity = new StringRequestEntity(soapRequestData,"application/soap+xml; charset=UTF-8; type=\"text/xml\"","UTF-8");

        postMethod.setRequestEntity(requestEntity);

加上basic身份认证：

HttpClient httpClient = new HttpClient();

        httpClient.getState().setCredentials(new AuthScope("host", 80, AuthScope.ANY_REALM),

                new UsernamePasswordCredentials("username", "password"));

        httpClient.getParams().setAuthenticationPreemptive(true);

最后，像正常的http请求一下，调用起来：

int statusCode = httpClient.executeMethod(postMethod);

		if(statusCode == 200) {

			System.out.println("调用成功！");

			String soapResponseData = postMethod.getResponseBodyAsString();

			System.out.println(soapResponseData);

		}

		else {

			System.out.println("调用失败！错误码：" + statusCode);

		}

这里的返回值就是webservice返回的xml，需要我们解析这个xml文件来得到数据。