How to implement a SQL like 'LIKE' operator in java?

Question

I need a comparator in java which has the same semantics as the sql \'like\' operator. For example:

myComparator.like(\"digital\",\"%ital%\");
myComparator.l         


        

Answer 1

i dont know exactly about the greedy issue, but try this if it works for you:

public boolean like(final String str, String expr)
  {
    final String[] parts = expr.split("%");
    final boolean traillingOp = expr.endsWith("%");
    expr = "";
    for (int i = 0, l = parts.length; i < l; ++i)
    {
      final String[] p = parts[i].split("\\\\\\?");
      if (p.length > 1)
      {
        for (int y = 0, l2 = p.length; y < l2; ++y)
        {
          expr += p[y];
          if (i + 1 < l2) expr += ".";
        }
      }
      else
      {
        expr += parts[i];
      }
      if (i + 1 < l) expr += "%";
    }
    if (traillingOp) expr += "%";
    expr = expr.replace("?", ".");
    expr = expr.replace("%", ".*");
    return str.matches(expr);
}