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