<dependency>
  <groupId>com.google.code.gson</groupId>
  <artifactId>gson</artifactId>
  <version>2.2.4</version>
</dependency>

public class Person {

  private String name;
  private int age;

  /**
   * @return the name
   */
  public String getName() {
    return name;
  }

  /**
   * @param name the name to set
   */
  public void setName(String name) {
    this.name = name;
  }

  /**
   * @return the age
   */
  public int getAge() {
    return age;
  }

  /**
   * @param age the age to set
   */
  public void setAge(int age) {
    this.age = age;
  }
  
  @Override
  public String toString()
  {
    return name + ":" +age;
  }
}

Gson gson = new Gson();
List<Person> persons = new ArrayList<Person>();
for (int i = 0; i < 10; i++) {
   Person p = new Person();
   p.setName("name" + i);
   p.setAge(i * 5);
   persons.add(p);
}
String str = gson.toJson(persons);

[{"name":"name0","age":0}]

Person person = gson.fromJson(str, Person.class);

List<Person> ps = gson.fromJson(str, new TypeToken<List<Person>>(){}.getType());
for(int i = 0; i < ps.size() ; i++)
{
   Person p = ps.get(i);
   System.out.println(p.toString());
}