Write in Java please!$7\mathrm{.}48$ Suppose a data file contains lines that consist of either a single inte$-$

ger, or the name of a file that contains more lines. Note that a data file

may reference several other files and the referenced files may them$-$

selves contain some additional file names, and so forth. Write a

method that reads a specified file and returns the sum of all the inte$-$

gers in the file and any files that are referenced. You may assume that

no file is referenced more than once.

For $7\mathrm{.}48$ the program should read the initial file name from the user. Attached is a sample data set for $7\mathrm{.}48$ If the initial file was

Test$1.$txt

then the call sequence is