code: public  <T> T eval(ELVars vars, String el, Class<T> returnType) throws ELEvalException {
      Utils.checkNotNull(vars, "vars");
      Utils.checkNotNull(el, "expression");
      Utils.checkNotNull(returnType, "returnType");
      VARIABLES_IN_SCOPE_TL.set(vars);
      try {
        return evaluate(vars, el, returnType);
      } finally {
        VARIABLES_IN_SCOPE_TL.set(null);
      }
    }
docs: Evaluates an EL.
  
  @param vars the variables to be available for the evaluation.
  @param el the EL string to evaluate.
  @param returnType the class the EL evaluates to.
  @return the evaluated EL as an instance of the specified return type.
  @throws ELEvalException if the EL could not be evaluated.