Here is a quick code snippet:
public static void main (String[] args)
{
/* Sample Space */
String[] strArr = new String[] {
"February_Report_files\\customerst.rptdesign",
"February_Report_files\\Top10Percent.rptdesign",
"February_Report_files\\TopNPercent.rptdesign",
"March_Report_files\\by_sup_ML.rptdesign",
"March_Report_files\\chart__cwong.rptdesign",
"March_Report_files\\HTML5 Chart.rptdesign",
};
/* Sort Sample Space */
Arrays.sort(strArr);
/* Initialize Result ArrayList */
List<String> resultList = new ArrayList<>();
/* Initialize */
String[] strInit = strArr[0].split("\\\\");
String prefix = strInit[0];
StringBuilder result = new StringBuilder(strInit[1]);
for(int i = 1; i < strArr.length; i++) {
/* Split Using Backslash */
String[] strSplit = strArr[i].split("\\\\");
if(strSplit[0].equals(prefix)) {
/* Append */
result.append("," + strSplit[1]);
} else {
/* Add Result To List */
resultList.add(result.toString());
/* Reset Prefix, Result Strings */
prefix = strSplit[0];
result = new StringBuilder(strSplit[1]);
}
}
/* Add Last Entry To List */
resultList.add(result.toString());
/* Print The Results */
for(int i = 0; i < resultList.size(); i++) {
System.out.println(resultList.get(i));
}
}
Output of this program:
customerst.rptdesign,Top10Percent.rptdesign,TopNPercent.rptdesign
by_sup_ML.rptdesign,chart__cwong.rptdesign,HTML5 Chart.rptdesign