POJO Creation from JSON Array (BufferReader)

I am trying to unmarshal the following JSON

[{
	"myId": "12851cb3087f51b4fb392b1fea36eef9508",
	"secondaryId": "787CFD4A-6B1D-4415-AD56-D075B535B890",
	"my_key": "keyABCD",
	"email": ""
}, {
	"myId": "12851cb3087f51b4fb392b1fea36eef9508",
	"secondaryId": "BFACD2F0-F5EF-4F05-AA6B-00E18CA907EF",
	"my_key": "keyABCD",
	"email": ""
}, {
	"myId": "12851cb3087f51b4fb392b1fea36eef9508",
	"secondaryId": "567DE8C0-B5B5-4961-B97A-A2DD374AEED1",
	"my_key": "keyABCD",
	"email": ""
}, {
	"myId": "12851cb3087f51b4fb392b1fea36eef9508",
	"secondaryId": "78a52d90-be6c-4d80-b79d-0e256028ba01",
	"my_key": "keyABCD",
	"email": "test@email.com"
}, {
	"myId": "12851cb3087f51b4fb392b1fea36eef9508",
	"secondaryId": "aeb148e7-fc88-4a71-8baa-63b6528e463e",
	"my_key": "keyABCD",
	"email": ""
}]

and already have a bufferreader (myBufferedReader) which has the above json. POJO

import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.Setter;
import lombok.ToString;

@ToString
@AllArgsConstructor
public class MyPOJO {
    @Getter @Setter private String myId;
    @Getter @Setter private String secondaryId;
    @Getter @Setter private String my_key;
    @Getter @Setter private String email;

}

On using below mapper -

ObjectMapper mapper = new ObjectMapper();
List<MyPOJO> eventList = mapper.readValue(myBufferedReader.readLine(),mapper.getTypeFactory().constructCollectionType(List.class, MyPOJO.class));

getting error. Please help. - (no Creators, like default construct, exist): cannot deserialize from Object value (no delegate- or property-based Creator)

If above is not the correct way, please suggest the best way to read from bufferreader and create list of pojo class mapped with json.

Regards,
Dan

Well, I am not a Master of all things Java JSON. I have a tool which I use whenever I need to parse JSON. Be aware that there are multiple tools for parsing JSON String's, but I am only going to post the solution for the version that I use. I, personally, do not get into Java's Component Annotations because they add such a tremendous amount of complexity, and do not add anything to value of the code. I am not here to prove my points, but I don't get into Java Beans.

There is a library called the GSON Library that (supposedly) can map JSON String's directly to Java Object's (POJO's as you called them). I am, unfortunately, unfamiliar with the GSON Tool, and it might actually be able to "automatically" build a class MyPOJO using Annotations as you have requested.

Here is my solution, which just uses the standard JSON Parsing Library which I call javax.json.* below. You would have to retrieve the JSON JAR by looking for it using a Google Search.

import java.io.*;
import javax.json.*;
public class S
{
// I am just going to create the class for parsing this
// If there is a GSON way to do this "Automatically", then you
// should not use this Answer I have written to Stack Overflow
public static class MyPOJO
{
public final String myId;
public final String secondaryId;
public final String myKey;
public final String email;
public MyPOJO(String myId, String secondaryId, String myKey, String email)
{ this.myId=myId; this.secondaryId=secondaryId; this.myKey=myKey; this.email=email; }
public String toString()
{
return
"myId:         " + myId         + '\n' +
"seoondaryId:  " + secondaryId  + '\n' +
"myKey:        " + myKey        + '\n' +
"email:        " + email        + "\n\n";
}
}
public static void main(String[] argv) throws IOException
{
// This reads the 'input.json' file into the Json parser using
// a simple java.io.FileReader
Reader r = new FileReader("input.json");
// This reads the file, and retrieves the JsonArray that you
// have provided in your original post.
JsonArray ja = Json
.createReader(r)
.readArray();
for (JsonObject jo : ja.getValuesAs(JsonObject.class))
{
String myId         = jo.getString("myId");
String secondaryId  = jo.getString("secondaryId");
String myKey        = jo.getString("my_key");
String email        = jo.getString("email");
// What *I* would do is to get rid of the Component Annotation, and simply 
// use a Constructor.  I don't strongly believe in Java's Annotation Classes,
// and I never use them.  If you can find an AUTOMATED WAY to do all of this,
// YOU SHOULD ... - if you are willing to learn it all.
// I HAVE NOT! :)
// If there is an easy way to **DIRECTLY MAP** a JSON Object to a specified
// class - and I believe that the GSON library is capable of directly mapping
// JSON Object's to GSON Java POJO's (Java Object's), but I have not used them
// before.  My own personal belief is that if it were easier, then learning the
// GSON JAR Library and Java Documentation (JavaDoc) for GSON.
// Here, though, a Constructor is what I would prefer myself.
MyPOJO mp = new MyPOJO(myId, secondaryId, myKey, email);
System.out.println(mp.toString());
}
}
}

The following is output by the above class to the Shell Terminal:

@cloudshell:~$ java S
myId:         12851cb3087f51b4fb392b1fea36eef9508
seoondaryId:  787CFD4A-6B1D-4415-AD56-D075B535B890
myKey:        keyABCD
email:        
myId:         12851cb3087f51b4fb392b1fea36eef9508
seoondaryId:  BFACD2F0-F5EF-4F05-AA6B-00E18CA907EF
myKey:        keyABCD
email:        
myId:         12851cb3087f51b4fb392b1fea36eef9508
seoondaryId:  567DE8C0-B5B5-4961-B97A-A2DD374AEED1
myKey:        keyABCD
email:        
myId:         12851cb3087f51b4fb392b1fea36eef9508
seoondaryId:  78a52d90-be6c-4d80-b79d-0e256028ba01
myKey:        keyABCD
email:        test@email.com
myId:         12851cb3087f51b4fb392b1fea36eef9508
seoondaryId:  aeb148e7-fc88-4a71-8baa-63b6528e463e
myKey:        keyABCD
email:        

Add your default constructor, empty constructor, by adding @NoArgConstructor top of your POJO class.
Then simply convert your buffer reader JSON string to a list of POJO like this:

List<MyPOJO> eventList = mapper.readValue(myBufferedReader, new TypeReference<List<MyPOJO>>(){});