Reading JSON Format

Hi,

How I can use an expression to read the below in a mapper to get individual values true or false? I am using as - $DocumentId.startsWith(“EBSPERSON_”)

[

{

"Content_ID":

"EBSPERSON_547229"

}

{

"Content_ID":

"EBSPERSONAD_547229"

}

{

"Content_ID":

"EBSPHONE_547229"

}

]