Need java script in renaming multiple illustrator file names

This should work, its not super refined, but it will do what you need.

1. run the file from illustrator (or indesign)
2. select a folder containing the files you want to rename
3. select a file containing the data of old name and new name. data must be saved as a tabbed text file with column 1 being old name and column 2 being new name
4. assumes all of the files will be .eps

I would suggest copying your files somewhere as a backup before making changes to them. 

couple of things you will need to open the file and change.

var TopFolder = Folder("PATH TO FOLDER OF FILES")
var DataFile = File("PATH TO TABBED TEXT FILE")

/* alternatively, you can use a selection each time you run, just comment the lines above out and uncomment the ones below */
//var TopFolder = Folder.selectDialog("Pick the Folder containing the Files you want to rename")
//var DataFile = File.selectDialog("Pick the File containing the Data for renaming")

if(TopFolder!=undefined && DataFile!=undefined){
    /*we open the data file and get the contents*/
    DataFile.open('r');
    DataFileContents = DataFile.read().split("\n"); /*split data on line returns*/
    DataFile.close();
    for(var a=0;a<DataFileContents.length;a++){
        DataFileContents[a] = DataFileContents[a].split("\t") /*split rows on tabs*/
    }
var allFiles = scanSubFolders(TopFolder); /*get all of the files in the TopFolder*/
var afL = allFiles.length;
for (var i=0;i<afL;i++){
    var ThisFile = allFiles[i]
    var ThisFileName = ThisFile.name.toString().substring(0,ThisFile.name.toString().lastIndexOf(".")) /*pull only the filename back and cut off the end*/
    var NewName = FindDataInArray(ThisFileName,DataFileContents)+".eps" /*get the new name and add .eps to it*/
    if(NewName!=false){
        ThisFile.rename(NewName);
    }
}
}
/*this is not the best function, but it works
this function assumes the data is set up so the old file name is array 0 and new name is array 1
*/

function FindDataInArray(DataToFind,ArrayToTest){
    for(var a=0;a<ArrayToTest.length;a++){
        if(ArrayToTest[a][0]==DataToFind) return ArrayToTest[a][1]
    }
    return false
}

function scanSubFolders(tFolder) { // folder object
    var sFolders = new Array();
    var allFiles = new Array();
    sFolders.push(tFolder);
    for (var j = 0; j < sFolders.length; j++) { // loop through folders            
        var procFiles = sFolders[j].getFiles();
        for (var i = 0; i < procFiles.length; i++) { // loop through this folder contents
            if (procFiles[i] instanceof File) {
                    allFiles.push(procFiles[i]);// if no search mask collect all files
            } else if (procFiles[i] instanceof Folder) {
                sFolders.push(procFiles[i]);// store the subfolder
                scanSubFolders(procFiles[i]);// search the subfolder
            }
        }
    }
    return allFiles;
};