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Convert List of user-defined datatype to String and back into List Java

There are times when it is necessary to convert a list of user-defined objects to string and later on retrieve it as a list in its original form. Example: like storing it into a Redis cache.
How do we do that? 
ObjectMapper

Steps:

1. ObjectMapper objectMapper = new ObjectMapper();
First, initialize ObjectMapper.

2. List<YourClass> listObj ;
Create and initialize your list of user-defined object.
where, YourClass is a class having multiple variables.
Example -
class YourClass{
String abc;
String xyz;
}

3. String convertedStr = objectMapper.writeValueAsString(listObj);
This is the string conversion of the list.

4. listObj = objectMapper.readValue(convertedStr, new TypeReference<List<YourClass>>();
And we are back with your list object.

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