Created attachment 36889 [details]
Data for investigation

A thread is continuously occupied by POI and no response is returned when the Excel SUBSTITUTE function is called.
It occurs when the second argument is blank(empty character).

However, it doesn't occur when using the same function on Microsoft Excel.(only occurs when calling from POI)

I called POI, which reads an Excel file with SUBSTITUTE function in some CELLs, from a web application deployed on GlassFish.
According to the thread dump, it seems that the thread has stopped at the line marked with "*" on the following code.

-------------------------------------------------------------
org.apache.poi.ss.formula.functions.Substitute


	private static String replaceAllOccurrences(String oldStr, String searchStr, String newStr) {
		StringBuffer sb = new StringBuffer();
		int startIndex = 0;
		int nextMatch = -1;
		while (true) {
			nextMatch = oldStr.indexOf(searchStr, startIndex);
			if (nextMatch < 0) {
				// store everything from end of last match to end of string
				sb.append(oldStr.substring(startIndex));
				return sb.toString();
			}
			// store everything from end of last match to start of this match
			sb.append(oldStr.substring(startIndex, nextMatch));
			sb.append(newStr);
*			startIndex = nextMatch + searchStr.length();
		}
	}
-------------------------------------------------------------


It occurs when using version 4.1.1, too.
If the allocated Java heap memory is small, java.lang.OutOfMemoryError is thrown instead.


I've attached the following materials that are necessary for the survey.

1. SUBSTITUTE.xls：Excel file which the problem occurs.
2. OutOfMemory.txt：Stack trace when java.lang.OutOfMemoryError was thrown.
3. ThreadDump.txt：Excerpt of the thread dump obtained when no response occurred.