現在主流上都用php寫微信公眾號后台，其實作為后端語言之一的java也可以實現。
這篇文章將對驗證服務器地址這一步做出實現。
參考資料：1.慕課網-《初識java微信公眾號開發》，2.微信公眾號開發者文檔http://mp.weixin.qq.com/wiki/8/f9a0b8382e0b77d87b3bcc1ce6fbc104.html
如圖，開發者在點擊提交后，微信服務器向公眾號后台服務器發送了四個參數，咱們把這四個參數封裝成一個類，就叫Signature吧
代碼都是myeclipse自動生成的（導包代碼已省略，由於視圖關系丟失了縮進）
public class Signature {
private String signature;
private String timestamp;
private String nonce;
private String echostr;
public Signature() {
super();
// TODO Auto-generated constructor stub
}
public Signature(String signature, String timestamp, String nonce,
String echostr) {
super();
this.signature = signature;
this.timestamp = timestamp;
this.nonce = nonce;
this.echostr = echostr;
}
public String getSignature() {
return signature;
}
public void setSignature(String signature) {
this.signature = signature;
}
public String getTimestamp() {
return timestamp;
}
public void setTimestamp(String timestamp) {
this.timestamp = timestamp;
}
public String getNonce() {
return nonce;
}
public void setNonce(String nonce) {
this.nonce = nonce;
}
public String getEchostr() {
return echostr;
}
public void setEchostr(String echostr) {
this.echostr = echostr;
}
@Override
public String toString() {
return "Signature [signature=" + signature + ", timestamp=" + timestamp
+ ", nonce=" + nonce + ", echostr=" + echostr + "]";
}
}
之后編寫servlet,對四個參數進行接收，new 一個Signarure對象，
public class WeixinServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
Signature sg = new Signature(req.getParameter("signature"),req.getParameter("timestamp"),
req.getParameter("nonce"),req.getParameter("echostr"));
PrintWriter out = resp.getWriter();
if(CheckUtil.checkSignature(sg)){
out.print(sg.getEchostr());
}
}
}
新建CheckUtil類實現校驗邏輯
public class CheckUtil {
private static final String token = "userwang";
public static boolean checkSignature(Signature sg){
String[] arr = new String[]{token,sg.getTimestamp(),sg.getNonce()};
//排序
Arrays.sort(arr);
//生成字符串
StringBuffer content = new StringBuffer();
for(int i=0;i<arr.length;i++){
content.append(arr[i]);
}
//sha1加密
String temp = getSha1(content.toString());
//比較
return temp.equals(sg.getSignature());
}
//加密算法
public static String getSha1(String str){
if(str == null || str.length()==0){
return null;
}
char hexDigits[] = {'0','1','2','3','4','5','6','7','8','9',
'a','b','c','d','e','f'};
try{
MessageDigest mdTemp = MessageDigest.getInstance("SHA1");
mdTemp.update(str.getBytes("UTF-8"));
byte[] md = mdTemp.digest();
int j = md.length;
char buf[] = new char[j*2];
int k = 0;
for(int i = 0;i<j;i++){
byte byte0 = md[i];
buf[k++] = hexDigits[byte0 >>> 4 & 0xf];
buf[k++] = hexDigits[byte0 & 0xf];
}
return new String(buf);
}catch(Exception e){
return null;
}
}
}
在web.xml中完成對servlet的配置之后，這一步基本就完成啦。
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www.ngrok.cc