Fix PoolRemoveFilesMessage#toString

There is an erroneous comma at the beginning of the file list.

Target: trunk
Require-notes: no
Require-book: no
Acked-by: Paul Millar <paul.millar@desy.de>
Patch: http://rb.dcache.org/r/6378/

modules/dcache/src/main/java/diskCacheV111/vehicles/PoolRemoveFilesMessage.java

@@ -1,5 +1,6 @@
 package diskCacheV111.vehicles;
 
+import com.google.common.base.Joiner;
 
 public class PoolRemoveFilesMessage extends PoolMessage {
     // this is sent from the LazyCleaner to the pool
@@ -9,26 +10,18 @@ public class PoolRemoveFilesMessage extends PoolMessage {
     private static final long serialVersionUID = 7090652304453652269L;
 
     public PoolRemoveFilesMessage(String poolName){
-	super(poolName);
-	setReplyRequired(true);
+        super(poolName);
+        setReplyRequired(true);
     }
 
     public void setFiles(String filesList[]) {
-    	_filesList = filesList;
+        _filesList = filesList;
     }
 
     public String[] getFiles() {
          return _filesList;
     }
     public String toString(){
-        StringBuilder sb = new StringBuilder();
-        sb.append(super.toString()).append(";RemoveFiles=");
-        if( _filesList != null ) {
-            for (String file : _filesList) {
-                sb.append(",").append(file);
-            }
-        }
-
-        return sb.toString();
+        return super.toString() + ";RemoveFiles=" + Joiner.on(",").join(_filesList);
     }
 }