使用Jackson的ObjectMapper对象的readValue和writeValueAsString方法可以进行转换。
对于简单基本类型或String类型的对象，使用上述方法可以满足。
但是如果要转换复杂类型Collection如 List<YourBean>，那么就需要先反序列化复杂类型为泛型的Collection Type。
如果是ArrayList<YourBean>那么使用ObjectMapper 的getTypeFactory().constructParametricType(collectionClass, elementClasses);
如果是HashMap<String,YourBean>那么 ObjectMapper 的getTypeFactory().constructParametricType(HashMap.class,String.class, YourBean.class);
例子如下，定义两个模型
package com.khlin.com.khlin.jackson.json.test;
import java.util.List;
public class Student {
private String familyname;
private String lastname;
private int age;
private String[] familyMembers;
private Place hometown;
public Place getHometown() {
return hometown;
}
public void setHometown(Place hometown) {
this.hometown = hometown;
}
public List<Place> getFavoritePlaces() {
return favoritePlaces;
}
public void setFavoritePlaces(List<Place> favoritePlaces) {
this.favoritePlaces = favoritePlaces;
}
private List<Place> favoritePlaces;
public String getFamilyname() {
return familyname;
}
public void setFamilyname(String familyname) {
this.familyname = familyname;
}
public String getLastname() {
return lastname;
}
public void setLastname(String lastname) {
this.lastname = lastname;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String[] getFamilyMembers() {
return familyMembers;
}
public void setFamilyMembers(String[] familyMembers) {
this.familyMembers = familyMembers;
}
}
package com.khlin.com.khlin.jackson.json.test;
public class Place {
private String province;
private String city;
public String getProvince() {
return province;
}
public void setProvince(String province) {
this.province = province;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
}
转换代码：
ObjectMapper objectMapper = new ObjectMapper();
Place hometown = new Place();
hometown.setProvince("guangdong");
hometown.setCity("jieyang");
Place place1 = new Place();
place1.setProvince("fujian");
place1.setCity("amoy");
Place place2 = new Place();
place2.setProvince("zhejiang");
place2.setCity("hangzhou");
List<Place> places = new ArrayList<Place>();
places.add(place1);
places.add(place2);
Student student = generateStudent("dacui", "lin", hometown, places);
Student student2 = generateStudent("ku", "lee", hometown, places);
List<Student> students = new ArrayList<Student>();
students.add(student);
students.add(student2);
String result = objectMapper.writeValueAsString(students);
System.out.println(result);
JavaType javaType = objectMapper.getTypeFactory()
.constructParametricType(ArrayList.class, Student.class);
List<Student> mapperStudents = objectMapper.readValue(result,
javaType);
Student mapperStudent1 = mapperStudents.get(0);
Student mapperStudent2 = mapperStudents.get(1);
System.out.println("success");