Jackson：高性能的JSON处理，处理json速度快。 Jackson可以轻松的将Java对象转换成json字符串和xml文档，同样也可以将json字符串、xml转换成Java对象。
代码如下:
package com.example.administrator.jsckson.ui; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.v7.app.AppCompatActivity; import android.util.Log; import com.example.administrator.jsckson.R; import com.example.administrator.jsckson.entity.Name; import com.example.administrator.jsckson.entity.Student; import com.fasterxml.jackson.annotation.JsonInclude; import com.fasterxml.jackson.core.JsonGenerator; import com.fasterxml.jackson.core.JsonParser; import com.fasterxml.jackson.core.type.TypeReference; import com.fasterxml.jackson.databind.DeserializationFeature; import com.fasterxml.jackson.databind.ObjectMapper; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.Date; import java.util.HashMap; import java.util.List; import java.util.Map; /** * Created on 2017/5/4. * Author:crs * Description:测试jackson */ public class TestJacksonActivity extends AppCompatActivity { private static final String TAG ="TestJacksonActivity" ; private Student student1; private ArrayList<Student> list; private HashMap<String, Student> map; @Override protected void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_test_jackson); /** * 1)JSON属于序列化与反序列化的内容 * 2)数据传输速度，数据解析速度 * 3)常用的json解析框架，以及一些配置 */ initData(); ObjectMapper mapper=getDefaultObjectMapper(); try { //1)序列化对象 Object---->String String s = mapper.writeValueAsString(student1); Log.i(TAG,s); //2)序列化集合 list---->String String s1 = mapper.writeValueAsString(list); Log.i(TAG,s1); //3)序列化集合 map---->String String s2 = mapper.writeValueAsString(map); Log.i(TAG,s2); //4)反序列化 json---->Object(这个应该是最常用的) Student jsonToObject = mapper.readValue(s, Student.class); Log.i(TAG,jsonToObject.toString()); //5)反序列化 json---->List List<Student> jsonToList = mapper.readValue(s1, new TypeReference<List<Student>>() {}); Log.i(TAG,jsonToList.toString()); //6)反序列化 json---->map Map<String,Student> jsonToMap = mapper.readValue(s2, new TypeReference<Map<String,Student>>() {}); Log.i(TAG,jsonToMap.toString()); } catch (Exception e) { e.printStackTrace(); } } private static ObjectMapper getDefaultObjectMapper() { /** * ObjectMapper是JSON操作的核心类，Jackson的所有JSON操作都是在ObjectMapper中实现。 * ObjectMapper有多个JSON序列化的方法，可以把JSON字符串保存File、OutputStream等不同的介质中。 * writeValueAsString(Object arg0)把arg0转成json序列，并把结果输出成字符串。 * JSON注解 Jackson提供了一系列注解，方便对JSON序列化和反序列化进行控制. */ ObjectMapper mapper = new ObjectMapper(); //1)设置将对象转换成JSON字符串时候(序列化时)；序列化与反序列化。//如果对象的属性为null或者“”，此属性不在进行序列化 mapper.setSerializationInclusion(JsonInclude.Include.NON_EMPTY); //JsonInclude.Include.NON_NULL;属性为NULL 不序列化 //JsonInclude.Include.ALWAYS ;默认 //2)设置有属性不能映射时不报错 mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false); mapper.configure(DeserializationFeature.ACCEPT_EMPTY_STRING_AS_NULL_OBJECT, true); mapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_CONTROL_CHARS, true); //3)不能包含ASCII码 mapper.configure(JsonGenerator.Feature.ESCAPE_NON_ASCII, true); //4)设置转换时的时间格式 mapper.setDateFormat(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")); return mapper; } private void initData() { //准备数据，创建对象 Name name1 = new Name("陈诗音", "音"); Name name2 = new Name("陈诗乐", "乐"); Name name3 = new Name("陈随心", "心"); student1 = new Student(1,name1,"语文",new Date()); Student student2 = new Student(2,name2,"数学",new Date()); Student student3 = new Student(3,name3,"英语",new Date()); list = new ArrayList<>(); list.add(student1); list.add(student2); list.add(student3); map = new HashMap<>(); map.put("1", student1); map.put("2",student2); map.put("3",student3); } } 实体模型: package com.example.administrator.jsckson.entity; import com.fasterxml.jackson.annotation.JsonFormat; import com.fasterxml.jackson.annotation.JsonIgnore; import com.fasterxml.jackson.annotation.JsonProperty; import java.util.Date; /** * Created on 2017/5/4. * Author:crs * Description:模型类student */ public class Student { @JsonIgnore //此注解用于属性上，作用是进行JSON操作时忽略该属性。 private int id; @JsonProperty("firstName")//此注解用于属性上，作用是把该属性的名称序列化为另外一个名称，如把Name属性序列化为firstName private Name name;//没有使用内部类 private String className; @JsonFormat(pattern = "yyyy年MM月dd日") //格式化日期属性 private Date birthDay; public Student(int id, Name name, String className, Date birthDay) { this.id = id; this.name = name; this.className = className; this.birthDay = birthDay; } public int getId() { return id; } public void setId(int id) { this.id = id; } public Name getName() { return name; } public void setName(Name name) { this.name = name; } public String getClassName() { return className; } public void setClassName(String className) { this.className = className; } public Date getBirthDay() { return birthDay; } public void setBirthDay(Date birthDay) { this.birthDay = birthDay; } @Override public String toString() { return "Student{" + "id=" + id + ", name=" + name + ", className='" + className + '\'' + ", birthDay=" + birthDay + '}'; } }