- 技术人生
- 反射妙用：超强通用年月日树 （轉）
在实际项目中，大家都要都有很多需要通过日期进行管理的数据，比如单据，考勤，日志等等。。。 这些数据对象都有一个共同的特点就是有一个字段是日期型。 于是我就利用JAVA的反射机制，写了一个通用年月日树。是用在RCP插件项目中的。稍加改造也能用到WEB项目中，核心算法不变。
1 import
java.lang.reflect.Field; 2 import
java.util.Calendar; 3 import
java.util.Date; 4 import
java.util.List; 5 import
org.eclipse.swt.SWT; 6 import
org.eclipse.swt.graphics.Image; 7 import
org.eclipse.swt.widgets.Tree; 8 import
org.eclipse.swt.widgets.TreeItem; 9
10 public class
GetYMDTree { 11
12 private static Image nodeImg = Activator.getImageDescriptor("icons/node.png"
).createImage(); 13
14 private static Image yearImg = Activator.getImageDescriptor("icons/year.png"
).createImage(); 15
16 private static Image monthImg = Activator.getImageDescriptor("icons/month.png"
).createImage(); 17
18 private static Image dayImg = Activator.getImageDescriptor("icons/day.png"
).createImage(); 19
20
21
22 public static void
buildTree(List list, TreeItem tree, String dateField, String nameField) { 23
tree.removeAll(); 24 if (list != null && list.size() > 0
) { 25 String year = ""
; 26 String month = ""
; 27 String day = ""
; 28 Object objt = list.get(0
); 29 Field dateF = null
; 30 Field nameF = null
; 31 try
{ 32 dateF =
objt.getClass().getDeclaredField(dateField); 33 dateF.setAccessible(true
); 34 nameF =
objt.getClass().getDeclaredField(nameField); 35 nameF.setAccessible(true
); 36 } catch
(SecurityException e) { 37
e.printStackTrace(); 38
tree.removeAll(); 39 return
; 40 } catch
(NoSuchFieldException e) { 41
e.printStackTrace(); 42
tree.removeAll(); 43 return
; 44
} 45 for
(Object obj : list) { 46 Calendar calendar =
Calendar.getInstance(); 47 String name = null
; 48 try
{ 49
calendar.setTime((Date) dateF.get(obj)); 50 name =
(String) nameF.get(obj); 51 } catch
(IllegalArgumentException e) { 52
e.printStackTrace(); 53
tree.removeAll(); 54 return
; 55 } catch
(IllegalAccessException e) { 56
e.printStackTrace(); 57
tree.removeAll(); 58 return
; 59
} 60 if
(year.equals(Integer.toString(calendar.get(Calendar.YEAR)))) { 61 if (month.equals(Integer.toString(calendar.get(Calendar.MONTH) + 1
))) { 62 if
(day.equals(Integer.toString(calendar.get(Calendar.DATE)))) { 63 TreeItem et = new TreeItem(tree.getItem(tree.getItemCount() - 1
).getItem( 64 tree.getItem(tree.getItemCount() - 1).getItemCount() - 1
) 65
.getItem( 66 tree.getItem(tree.getItemCount() - 1
).getItem( 67 tree.getItem(tree.getItemCount() - 1).getItemCount() - 1
) 68 .getItemCount() - 1
), SWT.NONE); 69
et.setText(name); 70
et.setData(obj); 71
et.setImage(nodeImg); 72 } else
{ 73 day =
Integer.toString(calendar.get(Calendar.DATE)); 74 TreeItem dt = new TreeItem(tree.getItem(tree.getItemCount() - 1
).getItem( 75 tree.getItem(tree.getItemCount() - 1).getItemCount() - 1
), SWT.NONE); 76
dt.setText(day); 77
dt.setImage(dayImg); 78
dt.setData(day); 79 TreeItem et = new
TreeItem(dt, SWT.NONE); 80
et.setText(name); 81
et.setData(obj); 82
et.setImage(nodeImg); 83
} 84 } else
{ 85 month = Integer.toString(calendar.get(Calendar.MONTH) + 1
); 86 day =
Integer.toString(calendar.get(Calendar.DATE)); 87 TreeItem mt = new TreeItem(tree.getItem(tree.getItemCount() - 1
), SWT.NONE); 88
mt.setText(month); 89
mt.setImage(monthImg); 90
mt.setData(month); 91 mt.setExpanded(true
); 92 TreeItem dt = new
TreeItem(mt, SWT.NONE); 93
dt.setText(day); 94
dt.setImage(dayImg); 95
dt.setData(day); 96 TreeItem et = new
TreeItem(dt, SWT.NONE); 97
et.setText(name); 98
et.setData(obj); 99
et.setImage(nodeImg);100
}101 } else
{102 year =
Integer.toString(calendar.get(Calendar.YEAR));103 month = Integer.toString(calendar.get(Calendar.MONTH) + 1
);104 day =
Integer.toString(calendar.get(Calendar.DATE));105 TreeItem yt = new
TreeItem(tree, SWT.NONE);106
yt.setText(year);107
yt.setImage(yearImg);108
yt.setData(year);109 TreeItem mt = new
TreeItem(yt, SWT.NONE);110
mt.setText(month);111
mt.setImage(monthImg);112
mt.setData(month);113 mt.setExpanded(true
);114 TreeItem dt = new
TreeItem(mt, SWT.NONE);115
dt.setText(day);116
dt.setImage(dayImg);117
dt.setData(day);118 TreeItem et = new
TreeItem(dt, SWT.NONE);119
et.setText(name);120
et.setData(obj);121
et.setImage(nodeImg);122 yt.setExpanded(true
);123
}124
}125
}126
}127
128
129
130 public static
Image getDayImg() {131 return
dayImg;132
}133
134
135
136 public static void
setDayImg(Image dayImg) {137 GetYMDTree.dayImg =
dayImg;138
}139
140
141
142 public static
Image getMonthImg() {143 return
monthImg;144
}145
146
147
148 public static void
setMonthImg(Image monthImg) {149 GetYMDTree.monthImg =
monthImg;150
}151
152
153
154 public static
Image getNodeImg() {155 return
nodeImg;156
}157
158
159
160 public static void
setNodeImg(Image nodeImg) {161 GetYMDTree.nodeImg =
nodeImg;162
}163
164
165
166 public static
Image getYearImg() {167 return
yearImg;168
}169
170
171
172 public static void
setYearImg(Image yearImg) {173 GetYMDTree.yearImg =
yearImg;174
}175
}176
