Gson之实例五

前面四篇博客基本上可以满足我们处理的绝大多数需求,但有时项目中对json有特殊的格式规定.比如下面的json串解析:

[{"tableName":"students","tableData":[{"id":1,"name":"李坤","birthDay":"Jun 22, 2012 9:54:49 PM"},{"id":2,"name":"曹贵生","birthDay":"Jun 22, 2012 9:54:49 PM"},{"id":3,"name":"柳波","birthDay":"Jun 22, 2012 9:54:49 PM"}]},{"tableName":"teachers","tableData":[{"id":1,"name":"米老师","title":"教授"},{"id":2,"name":"丁老师","title":"讲师"}]}]

分析之后我们发现使用前面博客中用到的都不好处理上面的json串.请看本文是如何处理的吧:

实体类:

1import java.util.Date;
2public class Student {
3 private int id;
4 private String name;
5 private Date birthDay;
6 public int getId() {
7 return id;
8 }
9 public void setId(int id) {
10 this.id = id;
11 }
12 public String getName() {
13 return name;
14 }
15 public void setName(String name) {
16 this.name = name;
17 }
18 public Date getBirthDay() {
19 return birthDay;
20 }
21 public void setBirthDay(Date birthDay) {
22 this.birthDay = birthDay;
23 }
24 @Override
25 public String toString() {
26 return "Student [birthDay=" + birthDay + ", id=" + id + ", name="
27 + name + "]";
28 }
29}
30
31public class Teacher {
32 private int id;
33 private String name;
34 private String title;
35 public int getId() {
36 return id;
37 }
38 public void setId(int id) {
39 this.id = id;
40 }
41 public String getName() {
42 return name;
43 }
44 public void setName(String name) {
45 this.name = name;
46 }
47 public String getTitle() {
48 return title;
49 }
50 public void setTitle(String title) {
51 this.title = title;
52 }
53 @Override
54 public String toString() {
55 return "Teacher [id=" + id + ", name=" + name + ", title=" + title
56 + "]";
57 }
58}

注意这里定义了一个TableData实体类:

1import java.util.List;
2public class TableData {
3 private String tableName;
4 private List tableData;
5 public String getTableName() {
6 return tableName;
7 }
8 public void setTableName(String tableName) {
9 this.tableName = tableName;
10 }
11 public List getTableData() {
12 return tableData;
13 }
14 public void setTableData(List tableData) {
15 this.tableData = tableData;
16 }
17}
18
19import java.util.ArrayList;
20import java.util.Date;
21import java.util.List;
22import com.google.gson.Gson;
23import com.google.gson.reflect.TypeToken;
24
25public class GsonTest5 {/*** @param args*/public static void main(String[] args) {
26    // 对象转为Json-->start
27    Student student1 = new Student();
28    student1.setId(1);
29    student1.setName("李坤");
30    student1.setBirthDay(new Date());
31    
32    Student student2 = new Student();
33    student2.setId(2);
34    student2.setName("曹贵生");
35    student2.setBirthDay(new Date());
36    
37    Student student3 = new Student();
38    student3.setId(3);
39    student3.setName("柳波");
40    student3.setBirthDay(new Date());
41    
42    List<Student> stulist = new ArrayList<Student>();
43    stulist.add(student1);
44    stulist.add(student2);
45    stulist.add(student3);
46    
47    Teacher teacher1 = new Teacher();
48    teacher1.setId(1);
49    teacher1.setName("米老师");
50    teacher1.setTitle("教授");
51    
52    Teacher teacher2 = new Teacher();
53    teacher2.setId(2);
54    teacher2.setName("丁老师");
55    teacher2.setTitle("讲师");
56    
57    List<Teacher> teacherList = new ArrayList<Teacher>();
58    teacherList.add(teacher1);
59    teacherList.add(teacher2);
60    
61    TableData td1 = new TableData();
62    td1.setTableName("students");
63    td1.setTableData(stulist);
64    TableData td2 = new TableData();
65    td2.setTableName("teachers");
66    td2.setTableData(teacherList);
67    List<TableData> tdList = new ArrayList<TableData>();
68    tdList.add(td1);
69    tdList.add(td2);
70    Gson gson = new Gson();
71    String s = gson.toJson(tdList);
72    System.out.println(s);
73    // 结果:[{"tableName":"students","tableData":[{"id":1,"name":"李坤","birthDay":"Jun 22, 2012 10:44:16 AM"},{"id":2,"name":"曹贵生","birthDay":"Jun 22, 2012 10:44:16 AM"},{"id":3,"name":"柳波","birthDay":"Jun 22, 2012 10:44:16 AM"}]},{"tableName":"teachers","tableData":[{"id":1,"name":"米老师","title":"教授"},{"id":2,"name":"丁老师","title":"讲师"}]}]
74    // 对象转为Json-->end//
75 /////////////////////////////////////////////////////////////////////
76    // 将json转为数据-->start    List<TableData> tableDatas2 = gson.fromJson(s,new TypeToken<List<TableData>>() {}.getType());
77    for (int i = 0; i < tableDatas2.size(); i++) {
78        TableData entityData = tableDatas2.get(i);
79        String tableName = entityData.getTableName();
80        List tableData = entityData.getTableData();
81        String s2 = gson.toJson(tableData);
82        // System.out.println(s2);
83        // System.out.println(entityData.getData());
84        
85            if (tableName.equals("students")) {
86                System.out.println("students");
87                List<Student> retStuList = gson.fromJson(s2,new TypeToken<List<Student>>() {
88            }.getType());
89        
90             for (int j = 0; j < retStuList.size(); j++) {
91                System.out.println(retStuList.get(j));
92                }
93            }else if (tableName.equals("teachers")) {
94            System.out.println("teachers");        
95            List<Teacher> retTchrList = gson.fromJson(s2,new TypeToken<List<Teacher>>() {}.getType());
96        
97            for (int j = 0; j < retTchrList.size(); j++) {
98                System.out.println(retTchrList.get(j));
99            }    
100        }
101    }
102    // Json转为对象-->end
103    }
104}

输出结果:

[{"tableName":"students","tableData":[{"id":1,"name":"李坤","birthDay":"Jun 22, 2012 10:04:12 PM"},{"id":2,"name":"曹贵生","birthDay":"Jun 22, 2012 10:04:12 PM"},{"id":3,"name":"柳波","birthDay":"Jun 22, 2012 10:04:12 PM"}]},{"tableName":"teachers","tableData":[{"id":1,"name":"米老师","title":"教授"},{"id":2,"name":"丁老师","title":"讲师"}]}]studentsStudent [birthDay=Fri Jun 22 22:04:12 CST 2012, id=1, name=李坤]Student [birthDay=Fri Jun 22 22:04:12 CST 2012, id=2, name=曹贵生]Student [birthDay=Fri Jun 22 22:04:12 CST 2012, id=3, name=柳波]teachersTeacher [id=1, name=米老师, title=教授]Teacher [id=2, name=丁老师, title=讲师]