Jacksonでjsonファイルを読み込んでみた

javaでjsonファイルを読み込むためにJacksonを使ってみました。
jsonの形式自体あまり理解できていませんが、配列を使う2つのケースを読み込みを試しました。
形式に関しては、ここに色々なパターンが書いてあり、参考にしています。
http://adobe.github.io/Spry/samples/data_region/JSONDataSetSample.html
POJOを使う読み込み方はいろいろなサイトを参照。

パターン1

・sample1.json

{
    "users": 
    [
        {
            "name": "taro",
            "country": "japan",
            "age": 12
        }, 
        {
            "name": "jack",
            "country": "us",
            "age": 20
        }
    ]
}

・JsonTest1.java

import java.io.File;
import java.io.IOException;
import java.util.List;

import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

public class JsonTest1 {

    public static void main(String args[]) throws JsonParseException,
            JsonMappingException, IOException {

        JsonTest1 converter = new JsonTest1();
        converter.parse("sample1.json");
    }

    public void parse(String fname) throws JsonParseException,
            JsonMappingException, IOException {
        UserList users = new ObjectMapper().readValue(new File(fname),
                UserList.class);
        for (User user : users.getUsers()) {
            System.out.println(user.getName());
            System.out.println(user.getCountry());
            System.out.println(user.getAge());
        }
    }

    public static class UserList {
        private List<User> users;

        public UserList() {
        }

        public List<User> getUsers() {
            return users;
        }

        public void setUsers(List<User> users) {
            this.users = users;
        }
    }

    public static class User {
        private String name;
        private String country;
        private int age;

        public User() {
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public String getCountry() {
            return country;
        }

        public void setCountry(String country) {
            this.country = country;
        }

        public int getAge() {
            return age;
        }

        public void setAge(int age) {
            this.age = age;
        }
    }
}

パターン2

・sample2.json

[
    {
        "pair": "USDEUR",
        "price": 1.3588,
        "change": -0.0088
    },
    {
        "pair": "USDJPY",
        "price": 102.4250,
        "change": 0.0049
    }
]

・JsonTest1.java

import java.io.File;
import java.io.IOException;
import java.util.List;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;
public class JsonTest2 {
    public static void main(String args[]) throws JsonParseException,
            JsonMappingException, IOException {
        JsonTest2 converter = new JsonTest2();
        converter.parse("sample2.json");
    }
    public void parse(String fname) throws JsonParseException,
            JsonMappingException, IOException {
        List<Currency> pairs = new ObjectMapper().readValue(new File(fname),
                new TypeReference<List<Currency>>() {
                });
        for (Currency c : pairs) {
            System.out.println(c.toString());
        }
    }
    public static class Currency {
        private String pair;
        private double price;
        private double change;
        public Currency() {
        }
        public String getPair() {
            return pair;
        }
        public void setParr(String parr) {
            this.pair = parr;
        }
        public double getPrice() {
            return price;
        }
        public void setPrice(double price) {
            this.price = price;
        }
        public double getChange() {
            return change;
        }
        public void setChange(double change) {
            this.change = change;
        }
        @Override
        public String toString() {
            return pair+":"+price+"("+change+"%)";
        }
    }
}