编程实现basic客户端认证
下面我们来示范一下如何使用basic认证。假设我们在basic.jsp中需要远程调用http://localhost:8080/ch104 /admin.jsp的内容。这时为了能够通过Spring Security的权限检测，我们需要在请求的头部加上basic所需的认证信息。
String username = "admin";
String password = "admin";
byte[] token = (username + ":" + password).getBytes("utf-8");
String authorization = "Basic " + new String(Base64.encodeBase64(token), "utf-8");
URL url = new URL("http://localhost:8080/ch104/admin.jsp");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestProperty("Authorization", authorization);
我们先将用户名和密码拼接成一个字符串，两者之间使用“:”分隔。
然后使用commons-codec的Base64将这个字符串加密。在进行basic认证的时候Spring Security会使用commons-codec把这段字符串反转成用户名和密码，再进行认证操作。
下一步为加密后得到的字符串添加一个前缀"Basic "，这样Spring Security就可以通过这个判断客户端是否使用了basic认证。
将上面生成的字符串设置到请求头部，名称为“Authorization”。Spring Security会在认证时，获取头部信息进行判断。
下面是通过鉴权认证访问指定地址的代码：
import java.io.IOException;import java.io.InputStream;import java.io.OutputStreamWriter;import java.net.HttpURLConnection;import java.net.URL;import java.util.Scanner;//import com.sun.org.apache.xerces.internal.impl.dv.util.Base64;import org.apache.commons.codec.binary.Base64;//import org.apache.taglibs.standard.lang.jpath.adapter.Convert;/** * This is a stub class with a main method to run an iDigi web service. */public class PostTest {/** * Run the web service request */public static void main(String[] args) {try {// Create url to the iDigi server for a given web service requestURL url = new URL("http://developer.idigi.com:80/ws/sci");HttpURLConnection conn = (HttpURLConnection) url.openConnection();conn.setDoOutput(true);conn.setRequestMethod("POST"); String username = "admin";String password = "admin";byte[] token = (username + ":" + password).getBytes("utf-8");String encodedAuthorization = new String(Base64.encodeBase64(token), "utf-8");conn.setRequestProperty("Authorization", "Basic "+ encodedAuthorization); // Send data to server conn.setRequestProperty("Content-Type", "text/xml");OutputStreamWriter out = new OutputStreamWriter(conn.getOutputStream());out.write("<!-- \r\n");out.write("See http://www.digi.com/wiki/developer/index.php/Rci for\r\n");out.write("an example of a python implementation on a NDS device to\r\n");out.write("handle this SCI request\r\n");out.write("-->\r\n");out.write("<sci_request version="1.0">\r\n");out.write(" <send_message>\r\n");out.write(" <targets>\r\n");out.write(" <device id="00000000-00000000-00409DFF-FF4A4244"/>\r\n");out.write(" </targets>\r\n");out.write(" <rci_request version="1.1">\r\n");out.write(" <do_command target="idigi_dia">\r\n");out.write(" <channel_dump/>\r\n");out.write(" </do_command>\r\n");out.write(" </rci_request>\r\n");out.write(" </send_message>\r\n");out.write("</sci_request>\r\n");out.close();// Get input stream from response and convert to Stringconn.disconnect();conn.setDoInput(true);InputStream is = conn.getInputStream();Scanner isScanner = new Scanner(is);StringBuffer buf = new StringBuffer();while(isScanner.hasNextLine()) {buf.append(isScanner.nextLine() +"\n");}String responseContent = buf.toString();// Output response to standard outSystem.out.println(responseContent);} catch (IOException e) { // Print any exceptions that occure.printStackTrace();}}}