/*

  * Copyright 2008 the original author or authors.

  *

  * Licensed under the Apache License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  *

  *      http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  * See the License for the specific language governing permissions and

  * limitations under the License.

  */

 package org.mockftpserver.core.util;

 import java.util.Collection;

 import java.util.Iterator;

 /**

  * Contains static String-related utility methods.

  *

  * @author Chris Mair

  * @version $Revision: 198 $ - $Date: 2008-12-10 21:47:32 -0500 (Wed, 10 Dec 2008) $

  */

 public class StringUtil {

     /**

      * Pad the specified String with spaces to the right to the specified width. If the length

      * of string is already equal to or greater than width, then just return string.

      *

      * @param string - the String to pad

      * @param width  - the target width

      * @return a String of at least width characters, padded on the right with spaces as necessary

      */

     public static String padRight(String string, int width) {

         int numSpaces = width - string.length();

         return (numSpaces > 0) ? string + spaces(numSpaces) : string;

     }

     /**

      * Pad the specified String with spaces to the left to the specified width. If the length

      * of string is already equal to or greater than width, then just return string.

      *

      * @param string - the String to pad

      * @param width  - the target width

      * @return a String of at least width characters, padded on the left with spaces as necessary

      */

     public static String padLeft(String string, int width) {

         int numSpaces = width - string.length();

         return (numSpaces > 0) ? spaces(numSpaces) + string : string;

     }

     /**

      * Join the Strings within the parts Collection, inserting the delimiter in between elements

      *

      * @param parts     - the Collection of Strings to join

      * @param delimiter - the delimiter String to insert between the parts

      * @return the Strings within the parts collection joined together using the specified delimiter

      */

     public static String join(Collection parts, String delimiter) {

         Assert.notNull(parts, "parts");

         Assert.notNull(delimiter, "delimiter");

         StringBuffer buf = new StringBuffer();

         Iterator iter = parts.iterator();

         while (iter.hasNext()) {

             String component = (String) iter.next();

             buf.append(component);

             if (iter.hasNext()) {

                 buf.append(delimiter);

             }

         }

         return buf.toString();

     }

     //--------------------------------------------------------------------------

     // Internal Helper Methods

     //--------------------------------------------------------------------------

     private static String spaces(int numSpaces) {

         StringBuffer buf = new StringBuffer();

         for (int i = 0; i < numSpaces; i++) {

             buf.append(" ");

         }

         return buf.toString();

     }

     /**

      * Private constructor to prevent instantiation. All members are static.

      */

     private StringUtil() {

     }

 }