stringreplace.java

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/*
* StringReplace.java
*
*/

package library;

/**
*
* Performs string replacement.  The
* methods contained in this class
* must be left non-static to allow
* for usage from a JSP, even though
* it makes more sense to be static.
*
* @author dms
* @version 1.0
*
*/
public class StringReplace {
  /**
  * A generic, variable length,
  * String replacement function.
  * Primarily a helper function
  * for the escape/unescape duo,
  * this was left public since
  * it may be of some use on its own.
  * @param s 	String to perform replacement on
  * @param seq   String sequence to look for
  * @param rep   String to replace with
  * @return String with replacements
  */
  public static String replace(String s, String seq, String rep) {
    int index = 0;
    StringBuffer sb = new StringBuffer();

    if (s.length() >= seq.length()) {
      do {
        int next = s.indexOf(seq, index);

        if (next == -1) {
          sb.append(s.substring(index));
          break;
        } else if (next == index) {
          sb.append(rep);
          index += seq.length();
        } else {
          sb.append(s.substring(index, next));
          sb.append(rep);
          index = next + seq.length();
        }
      } while (index != -1);
    } else {
      sb.append(s);
    }

    return sb.toString();
  }
}