Android 中Jackson的简单使用

第一步：下载Jackson的jar包http://pan.baidu.com/s/1qXHwtQ0

第二步：在gradle中导入jar包

第三步：创建ObjectMapper对象的单例

JacksonMapper.java

public class JacksonMapper {
    private static final ObjectMapper mapper = new ObjectMapper();

    private JacksonMapper() {
    }

    public static ObjectMapper getInstance() {
        return mapper;
    }
}

第四步：创建工具类JSONUtil.java

public class JSONUtil {

    public static String getJsonString(Object object) throws Exception {
        return JacksonMapper.getInstance().writeValueAsString(object);
    }

    public static Object toObject(String jsonString, Class cls) throws Exception {
        ObjectMapper objectMapper = new ObjectMapper();
        return objectMapper.readValue(jsonString, cls);
    }
}
第五步：使用

Birthday birthday = new Birthday(2000, 4, 28);
Person person = new Person("zhang san", 29, birthday);
try {
    Log.d(TAG, "onCreate: " + JSONUtil.getJsonString(person));
} catch (Exception e) {
    Log.e(TAG, "onCreate: " + e.toString());
    e.printStackTrace();
}

String jsonStr = "{\"name\":\"zhang san\",\"birthday\":{\"day\":28,\"month\":4,\"year\":2000},\"age\":29}";
try {
    Log.d(TAG, "onCreate: " + JSONUtil.toObject(jsonStr, Person.class));
} catch (Exception e) {
    e.printStackTrace();
}

第六步：Birthday.java

public class Birthday {
    private int year;
    private int month;
    private int day;

    public int getYear() {
        return year;
    }

    public void setYear(int year) {
        this.year = year;
    }

    public int getMonth() {
        return month;
    }

    public void setMonth(int month) {
        this.month = month;
    }

    public int getDay() {
        return day;
    }

    public void setDay(int day) {
        this.day = day;
    }

    public Birthday() {
        super();
    }

    public Birthday(int year, int month, int day) {
        super();
        this.year = year;
        this.month = month;
        this.day = day;
    }

    @Override
    public String toString() {
        return "Birthday [year=" + year + ", month=" + month + ", day=" + day
                + "]";
    }
}

Person.java

public class Person {
    private String name;
    private int age;
    private String number;
    private Birthday birthday;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public Birthday getBirthday() {
        return birthday;
    }

    public void setBirthday(Birthday birthday) {
        this.birthday = birthday;
    }

    public Person() {
        super();
    }

    public void setNumber(String number) {
        this.number = number;
    }

    public String getNumber() {
        return number;
    }

    public Person(String name, int age, Birthday birthday) {
        super();
        this.name = name;
        this.age = age;
        this.birthday = birthday;
    }

    @Override
    public String toString() {
        return "Person [name=" + name + ", age=" + age + ", birthday="
                + birthday + "]";
    }

结果如下：