|
1 package com.teamkonzept.lib.templates;
2
3 import java.io.*;
4
5 import org.apache.log4j.Category;
6 import com.teamkonzept.lib.*;
7
8 public class TKExpressionTag extends TKLabelTag
9 {
10 private static final Category CAT = Category.getInstance(TKExpressionTag.class);
11
12 public static final int TAG_TYPE = TKEvalTag.TAG_TYPE+1;
13
14 public TKExpressionTag( TKTemplateSyntax parent, String  name, boolean hasSubTags ) throws TKTemplateSyntaxException
15 {
16 super( parent, name, hasSubTags );
17 }
18
19 public static void operate ( String expression, TKVector vals, StringBuffer op ) throws TKTemplateSyntaxException
20 {
21 String opVal = op.toString();
22 int top = vals.size()-1;
23
24 if (Character.isDigit(op.charAt(0))) vals.addElement (new Integer (opVal));
25
26 else if (opVal.equals ("<")) {
27
28 if (top < 1) {
29 CAT.error ("*** TK_EXPRESSION: Zuwenig Operanden für '"+opVal+"' in '"+expression+"'");
30 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", opVal);
31 }
32
33 int val1 = ((Integer ) vals.elementAt(top-1)).intValue();
34 int val2 = ((Integer ) vals.elementAt(top)).intValue();
35 vals.setSize(top-1);
36
37 vals.addElement (new Integer (val1 < val2 ? 1 : 0));
38 }
39
40 else if (opVal.equals (">")) {
41
42 if (top < 1) {
43 CAT.error("*** TK_EXPRESSION: Zuwenig Operanden für '"+opVal+"' in '"+expression+"'");
44 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", opVal);
45 }
46
47 int val1 = ((Integer ) vals.elementAt(top-1)).intValue();
48 int val2 = ((Integer ) vals.elementAt(top)).intValue();
49 vals.setSize(top-1);
50
51 vals.addElement (new Integer (val1 > val2 ? 1 : 0));
52 }
53
54 else if (opVal.equals ("=")) {
55
56 if (top < 1) {
57 CAT.error("*** TK_EXPRESSION: Zuwenig Operanden für '"+opVal+"' in '"+expression+"'");
58 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", opVal);
59 }
60
61 int val1 = ((Integer ) vals.elementAt(top-1)).intValue();
62 int val2 = ((Integer ) vals.elementAt(top)).intValue();
63 vals.setSize(top-1);
64
65 vals.addElement (new Integer (val1 == val2 ? 1 : 0));
66 }
67
68 else if (opVal.equals ("!=")) {
69
70 if (top < 1) {
71 CAT.error("*** TK_EXPRESSION: Zuwenig Operanden für '"+opVal+"' in '"+expression+"'");
72 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", opVal);
73 }
74
75 int val1 = ((Integer ) vals.elementAt(top-1)).intValue();
76 int val2 = ((Integer ) vals.elementAt(top)).intValue();
77 vals.setSize(top-1);
78
79 vals.addElement (new Integer (val1 != val2 ? 1 : 0));
80 }
81
82 else if (opVal.equals ("<=")) {
83
84 if (top < 1) {
85 CAT.error ("*** TK_EXPRESSION: Zuwenig Operanden für '"+opVal+"' in '"+expression+"'");
86 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", opVal);
87 }
88
89 int val1 = ((Integer ) vals.elementAt(top-1)).intValue();
90 int val2 = ((Integer ) vals.elementAt(top)).intValue();
91 vals.setSize(top-1);
92
93 vals.addElement (new Integer (val1 <= val2 ? 1 : 0));
94 }
95
96 else if (opVal.equals (">=")) {
97
98 if (top < 1) {
99 CAT.error ("*** TK_EXPRESSION: Zuwenig Operanden für '"+opVal+"' in '"+expression+"'");
100 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", opVal);
101 }
102
103 int val1 = ((Integer ) vals.elementAt(top-1)).intValue();
104 int val2 = ((Integer ) vals.elementAt(top)).intValue();
105 vals.setSize(top-1);
106
107 vals.addElement (new Integer (val1 >= val2 ? 1 : 0));
108 }
109
110 else if (opVal.equals ("+")) {
111
112 if (top < 1) {
113 CAT.error("*** TK_EXPRESSION: Zuwenig Operanden für '"+opVal+"' in '"+expression+"'");
114 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", opVal);
115 }
116
117 int val1 = ((Integer ) vals.elementAt(top-1)).intValue();
118 int val2 = ((Integer ) vals.elementAt(top)).intValue();
119 vals.setSize(top-1);
120
121 vals.addElement (new Integer (val1 + val2));
122 }
123
124 else if (opVal.equals ("-")) {
125
126 if (top < 1) {
127 CAT.error ("*** TK_EXPRESSION: Zuwenig Operanden für '"+opVal+"' in '"+expression+"'");
128 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", opVal);
129 }
130
131 int val1 = ((Integer ) vals.elementAt(top-1)).intValue();
132 int val2 = ((Integer ) vals.elementAt(top)).intValue();
133 vals.setSize(top-1);
134
135 vals.addElement (new Integer (val1 - val2));
136 }
137
138 else if (opVal.equals ("*")) {
139
140 if (top < 1) {
141 CAT.error("*** TK_EXPRESSION: Zuwenig Operanden für '"+opVal+"' in '"+expression+"'");
142 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", opVal);
143 }
144
145 int val1 = ((Integer ) vals.elementAt(top-1)).intValue();
146 int val2 = ((Integer ) vals.elementAt(top)).intValue();
147 vals.setSize(top-1);
148
149 vals.addElement (new Integer (val1 * val2));
150 }
151
152 else if (opVal.equals ("/")) {
153
154 if (top < 1) {
155 CAT.error("*** TK_EXPRESSION: Zuwenig Operanden für '"+opVal+"' in '"+expression+"'");
156 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", opVal);
157 }
158
159 float val1 = ((Integer ) vals.elementAt(top-1)).floatValue();
160 int val2 = ((Integer ) vals.elementAt(top)).intValue();
161 vals.setSize(top-1);
162
163 vals.addElement (new Float (val1 / val2));
164 }
165
166 else if (opVal.equals ("%")) {
167
168 if (top < 1) {
169 CAT.error ("*** TK_EXPRESSION: Zuwenig Operanden für '"+opVal+"' in '"+expression+"'");
170 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", opVal);
171 }
172
173 int val1 = ((Integer ) vals.elementAt(top-1)).intValue();
174 int val2 = ((Integer ) vals.elementAt(top)).intValue();
175 vals.setSize(top-1);
176
177 vals.addElement (new Integer (val1 % val2));
178 }
179
180 else {
181 CAT.error ("*** TK_EXPRESSION: Unbekannter Operator '"+opVal+"' in '"+expression+"'");
182 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", opVal);
183 }
184
185 op.setLength(0);
186 }
187
188 public static String eval ( String expression ) throws TKTemplateSyntaxException
189 {
190 TKVector vals = new TKVector();
191 StringBuffer op = new StringBuffer ();
192 boolean isInt = false;
193
194 int i = 0;
195 while (i < expression.length()) {
196
198 char chr = expression.charAt(i);
199 if (chr == '\\')
200 {
201 if (++i >= expression.length())
202 {
203 break;
204 }
205 else
206 {
207 chr = expression.charAt(i);
208 }
209 }
210
211 if (Character.isWhitespace(chr)) {
212
213 if (op.length() != 0)
214 operate (expression,vals,op);
215 isInt = false;
216
217 } else if (Character.isDigit(chr)) {
218
219 if (op.length() != 0 && !isInt)
220 operate (expression,vals,op);
221 op.append (chr);
222 isInt = true;
223
224 } else {
225
226 if (op.length() != 0 && isInt)
227 operate (expression,vals,op);
228 op.append (chr);
229 isInt = false;
230 }
231
232 i++;
233 }
234
235 if (op.length() != 0) operate (expression,vals,op);
236
237 if (vals.size() > 1) {
238 CAT.error("*** TK_EXPRESSION: Zuviele Operanden für '"+expression+"'");
239 throw new TKTemplateSyntaxException("","WRONGEND","EXPRESSION", expression);
240 }
241
242 return vals.size() == 0 ? "" : vals.lastElement().toString();
243 }
244
245 public String apply( TKTemplateData td ) throws TKTemplateSyntaxException
246 {
247 return eval (getLabel( td ));
248 }
249
250 public void apply(TKTemplateData td, Writer writer)
251 throws TKTemplateSyntaxException, IOException
252 {
253 writer.write(eval (getLabel( td )));
254 }
255
256 }
257 |
Popular Tags |
Java API By Example, From Geeks To Geeks.