JSON: json is a java script object notation which used as a open standard format to transmit or communicate between server and client or web application. More Info
Jackson API: It is an open source streaming API to convert java collection into the json format and back forth.
Get JacksonAPI from : http://wiki.fasterxml.com/JacksonDownload
Example to convert hashmap into json:
import com.fasterxml.jackson.databind.ObjectMapper;
import java.util.HashMap;
import java.util.Map;
public class ConvertToJson {
public static void main(String[] args) {
try {
ObjectMapper mapper = new ObjectMapper();
String json = "";
Map<String, HashMap> map = new HashMap<String, HashMap>();
HashMap<String,String> hm = new HashMap<String,String>();
hm.put("fname", "Anshul");
hm.put("lname", "Mittal");
map.put("map", hm);
//convert map to JSON string
json = mapper.writeValueAsString(map);
System.out.println(json);
} catch (Exception e) {
e.printStackTrace();
}
}
}
Example to convert json into HashMap:
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.util.HashMap;
import java.util.Map;
public class ConvertToHashMap {
public static void main(String[] args) {
String j = "{\"map\":{\"lname\":\"Mittal\",\"fname\":\"Anshul\"}}";
JsonParser jp;
JavaType jt;
HashMap<String,String> map = new HashMap<String,String>();
ObjectMapper mapper = new ObjectMapper();
try {
//convert JSON string to Map
map = mapper.readValue(j,HashMap.class);
System.out.println(map);
} catch (Exception e) {
e.printStackTrace();
}
}
}
Note : Similarly do for other collections.
Jackson API: It is an open source streaming API to convert java collection into the json format and back forth.
Get JacksonAPI from : http://wiki.fasterxml.com/JacksonDownload
Example to convert hashmap into json:
import com.fasterxml.jackson.databind.ObjectMapper;
import java.util.HashMap;
import java.util.Map;
public class ConvertToJson {
public static void main(String[] args) {
try {
ObjectMapper mapper = new ObjectMapper();
String json = "";
Map<String, HashMap> map = new HashMap<String, HashMap>();
HashMap<String,String> hm = new HashMap<String,String>();
hm.put("fname", "Anshul");
hm.put("lname", "Mittal");
map.put("map", hm);
//convert map to JSON string
json = mapper.writeValueAsString(map);
System.out.println(json);
} catch (Exception e) {
e.printStackTrace();
}
}
}
Example to convert json into HashMap:
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.util.HashMap;
import java.util.Map;
public class ConvertToHashMap {
public static void main(String[] args) {
String j = "{\"map\":{\"lname\":\"Mittal\",\"fname\":\"Anshul\"}}";
JsonParser jp;
JavaType jt;
HashMap<String,String> map = new HashMap<String,String>();
ObjectMapper mapper = new ObjectMapper();
try {
//convert JSON string to Map
map = mapper.readValue(j,HashMap.class);
System.out.println(map);
} catch (Exception e) {
e.printStackTrace();
}
}
}
Note : Similarly do for other collections.
No comments:
Post a Comment