<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voidSystem.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StringString 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);