如何解析一个复杂的JSON字符串从Web服务响应中获取与Java中的GSON？

Question

大家好，

 I am new to Json/Gson. I have already looked all around the internet for help, but I  have seen nothing so similar to what I need to parse. So I am posting here, any help will be appreciated. 

我收到了来自我打电话这个JSON字符串的Web服务的响应：

 Json String = {"courses":[{"links":   [{"href":"https://xp.student.com/courses/6364145","rel":"self","title":"course"}]},   {"links": [{"href":"https://xp.student.com/courses/6364143","rel":"self","title":"course"}]}, 
     {"links": [{"href":"https://xp.student.com/courses/6364144","rel":"self","title":"course"}]}]} 

我已经做了代码最多的地步，我得到的“类JSON字符串“：

InputStreamReader reader = new InputStreamReader(httpConn.getInputStream()); 
     in = new BufferedReader(reader); 
    Gson gson = new Gson(); 
    Course courses = new Gson().fromJson(in,Course.class); 

我也创建了以下类：

 import ccSample.Type.Course.Link; 

     public class Course { 

     public Link links[]; 

     } 

     public class Link{ 
     public String href; 
     public String rel; 
     public String title; 
     public String getHref() { 
     return href; 
     } 
     public void setHref(String href) { 
     this.href = href; 
     } 
     public String getRel() { 
     return rel; 
     } 
     public void setRel(String rel) { 
     this.rel = rel; 
     } 
     public String getTitle() { 
     return title; 
     } 
     public void setTitle(String title) { 
     this.title = title; 
     } 

     } 





     but I am just getting a null courses object and do not know what I am missing,  any suggestions corrections are welcome! 

    Thank you very much :) 

Answer 1

它是一层洋葱。一次剥一个。您可以使用instanceof运算符和/或getClass().getName()方法调用来确定每个步骤中的含义，然后仔细检查它是否符合预期。

Answer 2

啊，疑难杂症..

您需要另一个包装的课程，因为在答复其包含在另一个JSON对象

public class Reply { 
    private Course[] courses; 

    public void setCourses(Course[] courses) { 
     this.courses = courses; 
    } 

    public Course[] getCourses() { 
     return courses; 
    } 
} 

然后

Reply reply = new Gson().fromJson(in,Reply.class);

应该做的它:)