多字段 java对象排序

最新推荐文章于 2024-03-12 07:59:58 发布

转载最新推荐文章于 2024-03-12 07:59:58 发布 · 117 阅读

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原文链接：http://www.cnblogs.com/ctaixw/p/5268780.html

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#java

public class ReflexUtil {
 static Logger logger = LoggerFactory.getLogger(ReflexUtil.class);

 //getMethod
 static public Object invokeMethod(String propertiesName, Object object) {
 try {
 if(object==null) return null;
 if (!propertiesName.contains(".")) {
 String methodName = "get"+getMethodName(propertiesName);
 Method method = object.getClass().getMethod(methodName);
 return method.invoke(object);
 }
 String methodName = "get"+getMethodName(propertiesName.substring(0,propertiesName.indexOf(".")));
 Method method = object.getClass().getMethod(methodName);
 return invokeMethod(propertiesName.substring(propertiesName.indexOf(".")+1), method.invoke(object));

 } catch (Exception e) {
 logger.error(e.toString(), e);
 return null;
 }
 }

 private static String getMethodName(String fildeName) {
 byte[] items = fildeName.getBytes();
 items[0] = (byte) ((char) items[0] - 'a' + 'A');
 return new String(items);
 }

 public static void main(String args[]) {
 Video video = new Video();
 Album album = new Album();
 album.setAlbumId(346l);
 video.setAlbum(album);
 video.setVideoId(126l);
 System.out.println(ReflexUtil.invokeMethod("album.albumId", video));
 }
}
 
  public 
  class 
  CompareUtil {
 
  //sort 1正序 -1 倒序  filed 多字段排序
 
  public 
  static 
  <t> Comparator createComparator(
  int 
  sort, String... filed) {
 
  return 
  new 
  ImComparator(sort, filed);
 
  }
 
  public 
  static 
  class 
  ImComparator 
  implements 
  Comparator {
 
  int 
  sort = 
  1
  ;
 
  String[] filed;
 
  public 
  ImComparator(
  int 
  sort, String... filed) {
 
  this
  .sort = sort == -
  1 
  ? -
  1 
  : 
  1
  ;
 
  this
  .filed = filed;
 
  }
 
  @Override
 
  public 
  int 
  compare(Object o1, Object o2) {
 
  int 
  result = 
  0
  ;
 
  for 
  (String file : filed) {
 
  Object value1 = ReflexUtil.invokeMethod(file, o1);
 
  Object value2 = ReflexUtil.invokeMethod(file, o2);
 
  if 
  (value1 == 
  null 
  || value2 == 
  null
  ) {
 
  continue
  ;
 
  }
 
  if 
  (!(value1 
  instanceof 
  Integer) || !(value1 
  instanceof 
  Integer)) {
 
  continue
  ;
 
  }
 
  int 
  v1 = Integer.valueOf(value1.toString());
 
  int 
  v2 = Integer.valueOf(value2.toString());
 
  if 
  (v1 == v2) 
  continue
  ;
 
  if 
  (sort == 
  1
  ) {
 
  return 
  v1 - v2;
 
  } 
  else 
  if 
  (sort == -
  1
  ) {
 
  return 
  v2 - v1;
 
  } 
  else 
  {
 
  continue
  ;
 
  }
 
  }
 
  return 
  result;
 
  }
 
  }
 
  public 
  static 
  void 
  main(String args[]) {
 
  LabelAlbum label1 = 
  new 
  LabelAlbum();
 
  label1.setLabelId(
  1
  ); label1.setSequnces(
  1
  );
 
  LabelAlbum label2 = 
  new 
  LabelAlbum();
 
  label2.setLabelId(
  1
  );label2.setSequnces(
  2
  );
 
  LabelAlbum label3 = 
  new 
  LabelAlbum();
 
  label3.setLabelId(
  3
  ); label3.setSequnces(
  4
  );
 
  LabelAlbum label4 = 
  new 
  LabelAlbum();
 
  label4.setLabelId(
  3
  );label4.setSequnces(
  3
  );
 
  LabelAlbum label5 = 
  new 
  LabelAlbum();
 
  label5.setLabelId(
  4
  );label5.setSequnces(
  2
  );
 
  List<labelalbum> list = 
  new 
  ArrayList<labelalbum>();
 
  list.add(label1);
 
  list.add(label2);
 
  list.add(label3);
 
  list.add(label4);
 
  list.add(label5);
 
  Collections.sort(list, CompareUtil.createComparator(
  1
  , 
  "labelId"
  ,
  "sequnces"
  ));
 
  for 
  (
  int 
  i = 
  0
  ; i < list.size(); i++) {
 
  LabelAlbum labelAlbum=list.get(i);
 
  System.out.println(
  "labelId:"
  +labelAlbum.getLabelId()+
  "  sequence："
  +labelAlbum.getSequnces());
 
  }
 
  }
 
  }</labelalbum></labelalbum></t>