+
+class BackupFilenameParts
+{
+ File file;
+
+ String base;
+
+ String templateStart;
+
+ int num;
+
+ int digits;
+
+ String templateEnd;
+
+ String extension;
+
+ boolean isBackupFile;
+
+ public BackupFilenameParts(File file, String base, String template, int digits,
+ String extension)
+ {
+ this(file.getName(), base, template, digits, extension);
+ }
+
+ public BackupFilenameParts(String filename, String base, String template,
+ int digits, String extension)
+ {
+ this.isBackupFile = false;
+
+ if (!(filename.startsWith(base) && filename.endsWith(extension)))
+ {
+ return;
+ }
+
+ int numcharstart = template.indexOf(BackupFiles.NUM_PLACEHOLDER);
+ String templateStart = template;
+ String templateEnd = "";
+ if (numcharstart > -1)
+ {
+ templateStart = template.substring(0, numcharstart);
+ templateEnd = template.substring(numcharstart + BackupFiles.NUM_PLACEHOLDER.length());
+ }
+ int startLength = base.length() + templateStart.length();
+ int endLength = templateEnd.length() + extension.length();
+ String numString = filename.substring(startLength, filename.length() - endLength + 1);
+
+ if (filename.length() >= startLength + digits + endLength
+ && filename.startsWith(base + templateStart)
+ && filename.endsWith(templateEnd + extension)
+ && numString.matches("[0-9]+"))
+ {
+ this.file = file;
+ this.base = base;
+ this.templateStart = templateStart;
+ this.num = Integer.parseInt(numString);
+ this.digits = digits;
+ this.templateStart = templateStart;
+ this.templateEnd = templateEnd;
+ this.isBackupFile = true;
+ }
+
+ }
+
+ public static String getBackupFilename(int index, String base,
+ String template,
+ int digits, String extension)
+ {
+ String numString = String.format("%0" + digits + "d", index);
+ String backupSuffix = template.replaceAll(BackupFiles.NUM_PLACEHOLDER,
+ numString);
+ String backupfilename = base + backupSuffix + extension;
+ return backupfilename;
+ }
+
+ public boolean isBackupFile()
+ {
+ return this.isBackupFile;
+ }
+
+ public int indexNum()
+ {
+ return this.num;
+ }
+}
\ No newline at end of file