<dependency>

            <groupId>com.fasterxml.jackson.core</groupId>

            <artifactId>jackson-databind</artifactId>

            <version>2.4.1</version>

        </dependency>

        <dependency>

            <groupId>org.codehaus.jackson</groupId>

            <artifactId>jackson-jaxrs</artifactId>

            <version>1.9.11</version>

        </dependency>

import java.io.IOException;

import com.fasterxml.jackson.core.JsonEncoding;

import com.fasterxml.jackson.core.JsonGenerator;

import com.fasterxml.jackson.databind.ObjectMapper;

public class TestJackSon {

    // 声明两个转换器

    private ObjectMapper objectMapper = null; // 一般使用ObjectMapper就已足够

    private JsonGenerator jsonGenerator = null; // 需要关闭

    /**

     * Java对象转换成JSON_1（objectMapper）

     */

    public void test1() {

        // 实例化转换器

        objectMapper = new ObjectMapper();

        // 测试

        try {

            User user = new User("ZhangSan", 25, "abc@163.com");

            // 直接输出转化结果到服务台，返回void

            System.out.println("直接输出到服务台：");

            objectMapper.writeValue(System.out, user); // user可替换为List,Map等等其他类型,都可正常输出

        } catch (Exception e) {

            e.printStackTrace();

        }

    }

    /**

     * Java对象转换成JSON_2（objectMapper）

     */

    public void test2() {

        // 实例化转换器

        objectMapper = new ObjectMapper();

        // 测试

        try {

            User user = new User("ZhangSan", 25, "abc@163.com");

            // 返回String

            String json = objectMapper.writeValueAsString(user); // user可替换为List,Map等等其他类型,都可正常输出

            System.out.println("返回String：");

            System.out.println(json);

        } catch (Exception e) {

            e.printStackTrace();

        }

    }

    /**

     * Json转Java对象（objectMapper）

     */

    public void test3() {

        // 实例化转换器

        objectMapper = new ObjectMapper();

        // 测试

        try {

            String json = "{\"name\":\"ZhangSan\",\"age\":25,\"emailAddress\":\"abc@163.com\"}";

            User user = objectMapper.readValue(json, User.class);

            System.out.println(user.getName() + " | " + user.getAge() + " | " + user.getEmailAddress());

        } catch (Exception e) {

            e.printStackTrace();

        }

    }

    /**

     * jsonGenerator的简单使用

     */

    public void test4() {

        // 实例化转换器

        objectMapper = new ObjectMapper();

        try {

            jsonGenerator = objectMapper.getJsonFactory().createJsonGenerator(System.out, JsonEncoding.UTF8);

            User user = new User("ZhangSan", 25, "abc@163.com");

            // 测试

            System.out.println("jsonGenerator:");

            jsonGenerator.writeObject(user); //直接输出到控制台

            // jsonGenerator需要关闭

            if (jsonGenerator != null) {

                jsonGenerator.flush();

            }

            if (!jsonGenerator.isClosed()) {

                jsonGenerator.close();

            }

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

    /**

     * 测试main

     */

    public static void main(String[] args) {

        TestJackSon test = new TestJackSon();

        test.test4();

    }

}

class User {

    public String name;

    public int age;

    public String emailAddress;

    /**

     * 构造函数

     */

    public User(String name, int age, String emailAddress) {

        super();

        this.name = name;

        this.age = age;

        this.emailAddress = emailAddress;

    }

    // getters/setters(略)

}

objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
XXX xxx = objectMapper.readValue(jsonResult, XXX.class);