quick and filthy

fileIn = new FileInputStream("data/config.csv")
fileOut = new PrintStream("output/seb.csv")

lst = []
while(true) {
    buf = fileIn.read()
    if(buf == -1) {
        break
    } else {
        lst.add((char)buf)
    }
}

strBuf = ""
lst.each { strBuf += it }
lines = strBuf.split("\n")
lst = []
lst.add(["","CA913426        ","20111207.2","REALKREDIT DANMARK A/S 7% OBL. 1996/2029-10-01 SER.23", "DDK0009258022","VPDKDKKK","VPD","BANKRUPTCY","\"NOTIFICATION, COMP\"","NEWM","VOLU","2012-01-20","2012-01-20","2012-01-20","2012-01-20","2012-01-20","2012-01-20 12:00:00","2012-01-20","12:30","2012-01-20","2012-01-20 - 2012-01-21","2012-01-20 - 2012-01-21","2012-01-20 - 2012-01-21","1000","100","500","250","10.45","1000","2.45","EUR","IE1234567891","Inter Sec","New Sec","IE1234567892","CA000012","CASH"])

lines.each { lst.add(it.split(",")) }

for(i in 1..lst.size()-1) {
    strBuf = ""
    for(j in 1..lst[i].size()-1) {
        if(lst[i][j] == "x") {
            lst[i][j] = lst[0][j]
        }
        strBuf += lst[i][j] + ","

    }
    fileOut.write(strBuf[0..-2] + "\n")
}