java - POJOs to byte array vs POJOs to json -

i'm newbie @ java. i'm confusing serialization , deserialization. so, i'm confusing 1 should use.
i'm looking round , found boon, jackson, gson (i'm using gson, of article using jackson , boon) json serialization. , serialize object byte array or binary object.
just, 1 faster , 1 should chose?
i'm make simple application, saving current state, document , other thing.

thanks in advance :)

serialize data means convert them sequence of bytes.

this sequence can interpreted sequence of readable chars happens in json, xml, yaml , on.

the same sequence can sequence of binary data not human readable.

there pro , cons each serialization approach.

pro of human readable:

• many existing libraries serialize deserialize data
• the data can debugged
• many existing libraries , apis use solution

cons:

• many bytes needed
• serialization , deserialization process can difficult , time machine consuming

pro , cons of binary data:

pro:

• faster serialization deserialization process
• less data transfer on network

cons:

• difficult read data passed on network
• not 1 representation of same data (bigendian or not example)