Android Gson解析

JSON转对象关键语法：gson.fromJson对象转JSON关键语法：gson.toJson================================================================================================================1、第一种，比如json字符串为：[{"name":"name0","age":0}]代码:Person person = gson.fromJson(str, Person.class);================================================================================================================2、第二种，转换成列表类型：[{"name":"name0","age":0},{"name":"name1","age":5}]代码:List<Person> ps = gson.fromJson(str, new TypeToken<List<Person>>(){}.getType());for(int i = 0; i < ps.size() ; i++){     Person p = ps.get(i);     System.out.println(p.toString());}可以看到上面的代码使用了TypeToken，它是gson提供的数据类型转换器，可以支持各种数据集合类型转换。================================================================================================================Convert numbers array into JSON string.(number数组转json字符串)int[] numbers = {1, 1, 2, 3, 5, 8, 13};Gson gson = new Gson();String numbersJson = gson.toJson(numbers);System.out.println("numbersJson = " + numbersJson);================================================================================================================Convert strings array into JSON string(string数组转json字符串)String[] days = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};String daysJson = gson.toJson(days);System.out.println("daysJson = " + daysJson);================================================================================================================Convert from JSON string to a primitive array of int.(从JSON字符串转换为原始数组int。)int[] fibonacci = gson.fromJson(numbersJson, int[].class);for (int i = 0; i < fibonacci.length; i++) {    System.out.print(fibonacci[i] + " ");}System.out.println("");================================================================================================================Convert from JSON string to a string array.(从JSON字符串转换为一个字符串数组。)String[] weekDays = gson.fromJson(daysJson, String[].class);for (int i = 0; i < weekDays.length; i++) {    System.out.print(weekDays[i] + " ");}System.out.println("");================================================================================================================Converting multidimensional array into JSON(多维数组转换成JSON)int[][] data = {{1, 2, 3}, {3, 4, 5}, {4, 5, 6}};String json = gson.toJson(data);System.out.println("Data = " + json);//// Convert JSON string into multidimensional array of int.//int[][] dataMap = gson.fromJson(json, int[][].class);for (int i = 0; i < data.length; i++) {    for (int j = 0; j < data[i].length; j++) {        System.out.print(data[i][j] + " ");    }    System.out.println("");}================================================================================================================Converts a collection of string object into JSON string.(转换成JSON字符串集的字符串对象。)List<String> names = new ArrayList<String>();names.add("Alice");names.add("Bob");names.add("Carol");names.add("Mallory");Gson gson = new Gson();String jsonNames = gson.toJson(names);System.out.println("jsonNames = " + jsonNames);================================================================================================================Converts a collection Student object into JSON string(将收集的学生对象转换成JSON字符串)Student a = new Student("Alice", "Apple St", new Date(2000, 10, 1));Student b = new Student("Bob", "Banana St", null);Student c = new Student("Carol", "Grape St", new Date(2000, 5, 21));Student d = new Student("Mallory", "Mango St", null);List<Student> students = new ArrayList<Student>();students.add(a);students.add(b);students.add(c);students.add(d);Gson gson = new Gson();String jsonStudents = gson.toJson(students);System.out.println("jsonStudents = " + jsonStudents);================================================================================================================Converts JSON string into a collection of Student object.(将JSON字符串为一个Student对象。)Type type = new TypeToken<List<Student>>(){}.getType();List<Student> studentList = gson.fromJson(jsonStudents, type);for (Student student : studentList) {    System.out.println("student.getName() = " + student.getName());}================================================================================================================json 串转化成 Java对象。()String json = "{\"name\":\"Duke\",\"address\":\"Menlo Park\",\"dateOfBirth\":\"Feb 1, 2000 12:00:00 AM\"}";Gson gson = new Gson();Student student = gson.fromJson(json, Student.class);System.out.println("student.getName()        = " + student.getName());System.out.println("student.getAddress()     = " + student.getAddress());System.out.println("student.getDateOfBirth() = " + student.getDateOfBirth());================================================================================================================Gson处理一个对象的某一字段。()Calendar dob = Calendar.getInstance();dob.set(1980, 10, 11);People people = new People("John", "350 Banana St.", dob.getTime());people.setSecret("This is a secret!");Gson gson = new Gson();String json = gson.toJson(people);System.out.println("json = " + json);输出结果：json = {"name":"John","address":"350 Banana St.","dateOfBirth":"Nov 11, 1980 8:47:04 AM"}实体类public class People {    private String name;    private String address;    private Date dateOfBirth;    private Integer age;    private transient String secret;    public People(String name, String address, Date dateOfBirth) {        this.name = name;        this.address = address;        this.dateOfBirth = dateOfBirth;    }    public String getSecret() {        return secret;    }    public void setSecret(String secret) {        this.secret = secret;    }}