Question

您好我从服务器动态获取access_token值以获取servlet请求：现在我想将access_taken值重新检入我的servlet程序。

{
    "access_token":"AQWP_EVkqdc7E0wD09J6msmjnUlvilhP304gUIDzl6KKgNxwnHyz_W9nOxS0IroDJwEfVr3n3O-IC9YKc3bjyuwYRm6qbKRiP3A2AzuDjo8ohZERZFRCMyfjjqqDjNJ5J5ReCQDhkFJam51eiqsOeXDg4U_c9XJzc1dUx7Qxck0p9RNE0",
    "expires_in": 5183999
}

我的代码如下：

public class Demo extends HttpServlet {
private static final long serialVersionUID = 1L;
private static final String PROTECTED_RESOURCE_URL = "http://api.linkedin.com/v1/people/~:(first-name,last-name,email-address)";

/**
 * @see HttpServlet#HttpServlet()
 */
public Demo() {
    super();
    // TODO Auto-generated constructor stub
}

/**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
 */
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException 
{
    PrintWriter out=response.getWriter();
    String authCode = request.getParameter("code");
    request.setAttribute("authCode",authCode);
    out.println(authCode);
    doPost(request,response);
}

/**
 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
 */
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException 
{
    PrintWriter out=response.getWriter();
    Object url=request.getAttribute("authCode");
    response.sendRedirect("https://www.linkedin.com/uas/oauth2/accessToken?grant_type=authorization_code&code="+url+"&redirect_uri=http://localhost:8080/LinkedinMails/dem&client_id=xxxxxxxxxxxxx&client_secret=xxxxxxxxxxxxxxx");

}

}

谢谢。

Answer 1

    public String doGet(String url) throws Exception {


    URL urlObj = new URL(url);
    HttpURLConnection conn = (HttpURLConnection) urlObj.openConnection();
    conn.setDoOutput(true);

    String line;
    StringBuffer buffer = new StringBuffer();
    BufferedReader reader = new BufferedReader(new InputStreamReader(
            conn.getInputStream()));

    while ((line = reader.readLine()) != null) {
        buffer.append(line);
    }

    reader.close();
    conn.disconnect();

    return buffer.toString();
}

现在，您可以从servlet调用此方法以在servlet中获取服务器响应。希望它对你有用。

Answer 2

您可以使用Gson或Jackson库来传达您的JSON响应。 使用杰克逊：

new ObjectMapper().readValue(result, LinkedIn.class);

其中，结果是您的JSON包含access_Token和expires _ in

LinkedIn.java

@JsonIgnoreProperties(ignoreUnknown=true)
public class LinkedIn
{
@JsonProperty("access_token")
private String accessToken;
@JsonProperty("expires_in")
private long expiresIn;

// Getters and setters for expiresOn and accessToken

}

在Servlet / Controller中

LinkedIn l= new ObjectMapper().readValue(result, LinkedIn.class); // Result is your JSON response which has access token and expires from LinkedIn
l.getAccessToken() ; // Returns you access token
l.getExpiresIn() // Returns you the expires time frame

}

使用JSONObject

 String s="{\n" +
                "    \"access_token\":\"AQWP_EVkqdc7E0wD09J6msmjnUlvilhP304gUIDzl6KKgNxwnHyz_W9nOxS0IroDJwEfVr3n3O-IC9YKc3bjyuwYRm6qbKRiP3A2AzuDjo8ohZERZFRCMyfjjqqDjNJ5J5ReCQDhkFJam51eiqsOeXDg4U_c9XJzc1dUx7Qxck0p9RNE0\",\n" +
                "    \"expires_in\": 5183999\n" +
                "}";  // This contains  your access token JSON

    JSONParser parser = new JSONParser();
    JSONObject o = (JSONObject) parser.parse(s);
    System.out.println("Access Token:   "+o.get("access_token")); //returns your access token
    System.out.println("Expires: "+o.get("expires_in"));

获取访问令牌JSON：

在你的Demo Servlet中，doPost方法代替sendRedirect做一个 http Post（使用Apache Http Client或java.net）调用url。完成HTTP Post后，您将获得一个Http响应，该响应将是application / json内容。所以得到这个String内容（包含application / json）。此字符串内容是LinkedIn发送给您的access_token。收到回复后，请执行以下操作：

JSONParser parser = new JSONParser(); JSONObject o = (JSONObject) parser.parse(responseString); // responseString is the JSON that you got from LinkedIn. System.out.println("Access Token: "+o.get("access_token")); //returns your access token System.out.println("Expires: "+o.get("expires_in"));

从servlet中的服务器响应中检索动态JSONObject值

2 个答案: