--- /dev/null
+/*
+ * Copyright (c) 2003-2005 The BISON Project
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+package peersim.util;
+
+import java.io.*;
+
+
+/**
+* Generates a series of filenames for classes that have to save e.g.
+* snapshots regularly.
+*/
+public class FileNameGenerator {
+
+
+/**
+* The number of filenames already returned.
+*/
+private long counter = 0;
+
+/** The prefix of the filename */
+public final String prefix;
+
+/** The extension of the filename */
+public final String ext;
+
+
+// ==================== initialization ==============================
+// ==================================================================
+
+
+/**
+* @param prefix all returned names will be prefixed by this
+* @param ext will be appended to all returned names
+*/
+public FileNameGenerator(String prefix, String ext) {
+
+ this.prefix=prefix;
+ this.ext=ext;
+}
+
+
+// ===================== methods ====================================
+// ==================================================================
+
+
+/**
+* Generates a name based on a counter.
+* The format of the name returned is {@link #prefix} followed by
+* an 8 digit zero padded number, followed by {@link #ext}.
+* The first number used is zero.
+* @return the next filename after increasing the counter
+*/
+public String nextCounterName() {
+
+ ByteArrayOutputStream baos = new ByteArrayOutputStream();
+ (new PrintStream(baos)).printf("%08d",counter);
+ counter++;
+ return prefix+baos.toString()+ext;
+}
+
+// ------------------------------------------------------------------
+
+/*
+public static void main(String args[]) {
+
+ FileNameGenerator fng = new FileNameGenerator(args[0],args[1]);
+ for(int i=0; i<100; ++i) System.err.println(fng.nextCounterName());
+}
+*/
+}
+
