basic-lib/src/main/java/com/streamsets/pipeline/stage/processor/fieldrenamer/FieldRenamerProcessor.java
private static String escapeQuotedSubstring(String input) {
    String[] parts = input.split("'");
    StringBuilder output = new StringBuilder(input.length() * 2);
    for (int i = 0; i < parts.length; i++) {
      if ((i % 2) == 1) {
        output.append("'").append(parts[i].replace("|", "\\|")).append("'");
      } else {
        output.append(parts[i]);
      }
    }
    return output.toString();
  }
private static String escapeQuotedSubstring(String input) {
    String[] parts = input.split("'");
    StringBuilder output = new StringBuilder(input.length() * 2);
    for (int i = 0; i < parts.length; i++) {
      if ((i % 2) == 1) {
        output.append("'").append(parts[i].replace("|", "\\|")).append("'");
      } else {
        output.append(parts[i]);
      }
    }
    return output.toString();
  }
Add backslash to escape the | character within quoted sections of the
input string.  This prevents the | from being processed as part of a regex.
@param input Contains the field name to process.
@return New string