Java String remove white spaces

//package com.demo2s;

public class Main {
  public static void main(String[] argv) throws Exception {
    String str = "       de         mo2s .c o m";
    System.out.println(deleteWhitespace(str));
  }/*from w  ww. j  av a 2  s. com*/

  /**
   * <p>
   * Deletes all whitespaces from a String as defined by
   * {@link Character#isWhitespace(char)}.
   * </p>
   *
   * <pre>
   * deleteWhitespace(null)         = null
   * deleteWhitespace("")           = ""
   * deleteWhitespace("abc")        = "abc"
   * deleteWhitespace("   ab  c  ") = "abc"
   * </pre>
   *
   * @param str
   *          the String to delete whitespace from, may be null
   * @return the String without whitespaces, <code>null</code> if null String
   *         input
   */
  public static String deleteWhitespace(String str) {
    if (isEmpty(str)) {
      return str;
    }
    int sz = str.length();
    char[] chs = new char[sz];
    int count = 0;
    for (int i = 0; i < sz; i++) {
      if (!Character.isWhitespace(str.charAt(i))) {
        chs[count++] = str.charAt(i);
      }
    }
    if (count == sz) {
      return str;
    }
    return new String(chs, 0, count);
  }

  /**
   * <p>
   * Checks if a String is empty ("") or null.
   * </p>
   *
   * <pre>
   * isEmpty(null)      = true
   * isEmpty("")        = true
   * isEmpty(" ")       = false
   * isEmpty("bob")     = false
   * isEmpty("  bob  ") = false
   * </pre>
   *
   * <p>
   * NOTE: This method changed in Lang version 2.0. It no longer trims the String.
   * That functionality is available in isBlank().
   * </p>
   *
   * @param str
   *          the String to check, may be null
   * @return <code>true</code> if the String is empty or null
   */
  public static boolean isEmpty(String str) {
    return str == null || str.length() == 0;
  }

}

/*
 * 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.
 */