How to handle static json payload external file

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it will convert json into string

package LibaryAPI;

import static io.restassured.RestAssured.given;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;

import org.testng.annotations.Test;

import InputFiles.LibaryMethods;
import InputFiles.ResuableMethods;
import io.restassured.RestAssured;
import io.restassured.path.json.JsonPath;

public class StaticJson {
@Test
public void addBook() throws IOException {

RestAssured.baseURI="http://216.10.245.166";
// Add the book to the Libary- POST
//Given input data
String res= given().headers("Content-Type","application/json").body(GenerateStringFroResource("C:\\Users\\abc\\Desktop\\API\\addBook.json"))
//submit- WHEN

.when().post("Library/Addbook.php")
//Response- THEN
.then().assertThat().statusCode(200).extract().response().asString();

JsonPath js1= ResuableMethods.rattoJson(res);
String responseMessage= js1.get("ID");
System.out.println(responseMessage);
}
public static String GenerateStringFroResource (String path) throws IOException
{
return new String (Files.readAllBytes(Paths.get(path)));


}
}

save below in notepad and pass the path =-static

C:\\Users\\abc\\Desktop\\API\\addBook.json

{

"name":"Learn Appium Automation with RPA",

"isbn":"BookNo",

"aisle":"007788",

"author":"Sudheer chittireddy"

}