Customize nested labels to implement if else

Three tag classes: poweriftag is external and used to judge. powernotag is else when poweryestag indicates if (true).]

 

 

Poweriftag. Java

1. Package AA;
2. Import java. Io. ioexception;
4. Import javax. servlet. jsp. jspexception;
5. Import javax. servlet. jsp. jsptagexception;
6. Import javax. servlet. jsp. jspwriter;
7. Import javax. servlet. jsp. tagext. tagsupport;
9. Public class poweriftag extends tagsupport {
10. Private string list;
11. Private string name;
12. Private Boolean is;
14. Public Boolean ISIS (){
15. Return is;
16. }
18. Public void setis (Boolean is ){
19. This. Is = is;
20. }
22. Public String getlist (){
23. Return list;
24. }
26. Public void setlist (string list ){
27. This. List = List;
28. }
30. Public String getname (){
31. Return name;
32. }
34. Public void setname (string name ){
35. This. Name = Name;
36. }
38. Public int dostarttag () throws jspexception {
39. If (name! = NULL &&! Name. Equals ("") & list! = NULL &&! List. Equals (""))
40. {
41. // The following key code can be changed as needed.
42. Object o = This. pagecontext. getsession (). getattribute (name );
43. If (O instanceof string)
44. {
45. String astr [] = List. Split (",");
46. String ostr = (string) O;
47. For (INT I = 0; I <astr. length; I ++)
48. {
49. If (! Astr [I]. Equals ("") & ostr. indexof (astr [I])>-1)
50. {
51. This. Is = true;
52. Break;
53. }
54. }
55. }
56. } Else
57. {
58. This. Is = false;
59. }
60. Return this. eval_page;
61. }
62. }

 

Poweryestag. Java

80. Package AA;
82. Import java. Io. ioexception;
84. Import javax. servlet. jsp. jspexception;
85. Import javax. servlet. jsp. jsptagexception;
86. Import javax. servlet. jsp. jspwriter;
87. Import javax. servlet. jsp. tagext. Tag;
88. Import javax. servlet. jsp. tagext. tagsupport;
90. Public class poweryestag extends tagsupport {
92. Public int dostarttag () throws jspexception {
93. Tag T = findancestorwithclass (this, poweriftag. Class );
94. If (T! = NULL)
95. {
96. Poweriftag parent = (poweriftag) T;
97. If (parent. ISIS ())
98. {
99. Return eval_page;
100. }
101. }
102. Return skip_body;
103. }
104. }

Powernotag. Java

106. Package AA;
108. Import java. Io. ioexception;
110. Import javax. servlet. jsp. jspexception;
111. Import javax. servlet. jsp. jsptagexception;
112. Import javax. servlet. jsp. jspwriter;
113. Import javax. servlet. jsp. tagext. Tag;
114. Import javax. servlet. jsp. tagext. tagsupport;
116. Public class powernotag extends tagsupport {
118. Public int dostarttag () throws jspexception {
119. Tag T = findancestorwithclass (this, poweriftag. Class );
120. If (T! = NULL)
121. {
122. Poweriftag parent = (poweriftag) T;
123. If (! Parent. ISIS ())
124. {
125. Return eval_page;
126. }
127. }
128. Return skip_body;
129. }
130. }

Powerif. TLD

1. <? XML version = "1.0" encoding = "UTF-8"?>
2. <Taglib>
3. <Tlib-version> 1.0 </tlib-version>
4. <JSP-version> 1.2 </JSP-version>
6. <Tag>
7. <Name> PIF </Name>
8. <Tag-class> AA. poweriftag </Tag-class>
9. <Attribute>
10. <Name> List </Name>
11. <Required> true </required>
12. <Rtexprvalue> true </rtexprvalue>
13. </Attribute>
14. <Attribute>
15. <Name> name </Name>
16. <Required> true </required>
17. <Rtexprvalue> true </rtexprvalue>
18. </Attribute>
19. </Tag>
20. <Tag>
21. <Name> pyes </Name>
22. <Tag-class> AA. poweryestag </Tag-class>
23. </Tag>
24. <Tag>
25. <Name> PNO </Name>
26. <Tag-class> AA. powernotag </Tag-class>
27. </Tag>
28. </Taglib>

Example:

<TD>
<Powerif: PIF name = "functstr" list = "01010102">
<Powerif: pyes>
<A href = "/company. Do? Method = preupdate & companycode =$ {company. companycode} "onclick =" alink (this); ">$ {company. companycode} </a>
</Powerif: pyes>
<Powerif: PNO>
$ {Company. companycode}
</Powerif: PNO>
</Powerif: PIF>
</TD>

 

Why do you need to customize tags? Some labels written by others may not be suitable for your own needs. As I wrote about permission judgment, pay attention to flexibility when using tags.

You can modify the Business Code in the poweriftag according to your needs. Now I am judging the permissions. You can also change the permissions according to your project requirements.