1   /**
2    * Copyright (c) 2000-2009 Liferay, Inc. All rights reserved.
3    *
4    * The contents of this file are subject to the terms of the Liferay Enterprise
5    * Subscription License ("License"). You may not use this file except in
6    * compliance with the License. You can obtain a copy of the License by
7    * contacting Liferay, Inc. See the License for the specific language governing
8    * permissions and limitations under the License, including but not limited to
9    * distribution rights of the Software.
10   *
11   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
12   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
13   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
14   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
15   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
16   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
17   * SOFTWARE.
18   */
19  
20  package com.liferay.portal.kernel.util;
21  
22  import java.io.Serializable;
23  
24  import java.util.Comparator;
25  
26  /**
27   * <a href="OrderByComparator.java.html"><b><i>View Source</i></b></a>
28   *
29   * @author Brian Wing Shun Chan
30   *
31   */
32  public abstract class OrderByComparator implements Comparator, Serializable {
33  
34      public abstract int compare(Object obj1, Object obj2);
35  
36      public String getOrderBy() {
37          return null;
38      }
39  
40      public String[] getOrderByFields() {
41          String orderBy = getOrderBy();
42  
43          if (orderBy == null) {
44              return null;
45          }
46  
47          String[] parts = StringUtil.split(orderBy);
48  
49          String[] fields = new String[parts.length];
50  
51          for (int i = 0; i < parts.length; i++) {
52              String part = parts[i];
53  
54              int x = part.indexOf(StringPool.PERIOD);
55              int y = part.indexOf(StringPool.SPACE, x);
56  
57              if (y == -1) {
58                  y = part.length();
59              }
60  
61              fields[i] = part.substring(x + 1, y);
62          }
63  
64          return fields;
65      }
66  
67      public boolean isAscending() {
68          String orderBy = getOrderBy();
69  
70          if ((orderBy == null) || orderBy.toUpperCase().endsWith(" DESC")) {
71              return false;
72          }
73          else {
74              return true;
75          }
76      }
77  
78      public String toString() {
79          return getOrderBy();
80      }
81  
82  }