1.  Json字符串转换为java对象

Json2Bean.java

package jackson;

import java.io.IOException;

import org.codehaus.jackson.map.ObjectMapper;

public class Json2Bean {

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

      String jsonStr = "{\"name\":\"Morris\",\"age\":\"22\",\"sex\":\"男\"}";

      ObjectMapper mapper = new ObjectMapper();

      Person person = mapper.readValue(jsonStr, Person.class);

      System.out.println(person);

   }

}

Json2List.java

package jackson;

import java.io.IOException;

import java.util.LinkedHashMap;

import java.util.List;

import org.codehaus.jackson.map.ObjectMapper;

public class Json2List {

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

      String jsonStr = "[{\"name\":\"Bob\",\"age\":\"33\",\"sex\":\"女\"},"

           + "{\"name\":\"Morris\",\"age\":\"22\",\"sex\":\"男\"}]";

      ObjectMapper mapper = new ObjectMapper();

      List<LinkedHashMap<String, String>> list = mapper.readValue(jsonStr, List.class);

      for (LinkedHashMap<String, String> linkedHashMap : list) {

        for (String key:linkedHashMap.keySet()) {

           System.out.println(key+":"+linkedHashMap.get(key));

        }

      }

   }

}

Json2Map.java

package jackson;

import java.io.IOException;

import java.util.Map;

import java.util.Set;

import org.codehaus.jackson.map.ObjectMapper;

public class Json2Map {

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

      String jsonStr = "{\"success\":true,\"A\":{\"address\": \"address2\",\"name\":\"haha2\",\"id\":2,\"email\":\"email2\"},"+

                "\"B\":{\"address\":\"address\",\"name\":\"haha\",\"id\":1,\"email\":\"email\"}}";

      ObjectMapper mapper = new ObjectMapper();

      Map map = mapper.readValue(jsonStr, Map.class);

      Set keySet = map.keySet();

      for (Object key : keySet) {

        System.out.println(key+":"+map.get(key));

      }

   }

}

Json2Array.java

package jackson;

import java.io.IOException;

import org.codehaus.jackson.map.ObjectMapper;

public class Json2Array {

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

      String jsonStr = "[{\"name\":\"Bob\",\"age\":\"33\",\"sex\":\"女\"},"

           + "{\"name\":\"Morris\",\"age\":\"22\",\"sex\":\"男\"}]";

      ObjectMapper mapper = new ObjectMapper();

      Person[] persons = mapper.readValue(jsonStr, Person[].class);

      for (Person person : persons) {

        System.out.println(person);

      }

   }

}