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1
29
30 package com.caucho.el;
31
32 import com.caucho.vfs.WriteStream;
33
34 import javax.el.ELContext;
35 import javax.el.ELException;
36 import java.io.IOException  ;
37
38
41 public class CmpExpr extends AbstractBooleanExpr {
42 private int _op;
43 private Expr _left;
44 private Expr _right;
45
46
53 private CmpExpr(int op, Expr left, Expr right)
54 {
55 _op = op;
56 _left = left;
57 _right = right;
58 }
59
60
67 static Expr create(int op, Expr left, Expr right)
68 {
69 switch (op) {
70 case LT:
71 return new LtExpr(left, right);
72 case LE:
73 return new LeExpr(left, right);
74 case GT:
75 return new GtExpr(left, right);
76 case GE:
77 return new GeExpr(left, right);
78 case EQ:
79 return new EqExpr(left, right);
80 case NE:
81 return new NeExpr(left, right);
82 }
83
84 return new CmpExpr(op, left, right);
85 }
86
87
90 @Override
91 public boolean isConstant()
92 {
93 return _left.isConstant() && _right.isConstant();
94 }
95
96
101 @Override
102 public boolean evalBoolean(ELContext env)
103 throws ELException
104 {
105 Object aObj = _left.getValue(env);
106 Object bObj = _right.getValue(env);
107
108 if (aObj == null || bObj == null) {
109 return false;
111 }
112
113 if (aObj == bObj)
114 return _op == LE || _op == GE;
115
116 if (aObj instanceof Double || aObj instanceof Float ||
117 bObj instanceof Double || bObj instanceof Float ) {
118 double a = toDouble(aObj, env);
119 double b = toDouble(bObj, env);
120
121 switch (_op) {
122 case LT: return a < b;
123 case LE: return a <= b;
124 case GT: return a > b;
125 case GE: return a >= b;
126 }
127 }
128
129 if (aObj instanceof Number || bObj instanceof Number ) {
130 double a = toDouble(aObj, env);
134 double b = toDouble(bObj, env);
135
136 switch (_op) {
137 case LT: return a < b;
138 case LE: return a <= b;
139 case GT: return a > b;
140 case GE: return a >= b;
141 }
142 }
143
144 if (aObj instanceof String || bObj instanceof String ) {
145 String a = toString(aObj, env);
146 String b = toString(bObj, env);
147
148 int cmp = a.compareTo(b);
149
150 switch (_op) {
151 case LT: return cmp < 0;
152 case LE: return cmp <= 0;
153 case GT: return cmp > 0;
154 case GE: return cmp >= 0;
155 }
156 }
157
158 if (aObj instanceof Comparable ) {
159 int cmp = ((Comparable ) aObj).compareTo(bObj);
160
161 switch (_op) {
162 case LT: return cmp < 0;
163 case LE: return cmp <= 0;
164 case GT: return cmp > 0;
165 case GE: return cmp >= 0;
166 }
167 }
168
169 if (bObj instanceof Comparable ) {
170 int cmp = ((Comparable ) bObj).compareTo(aObj);
171
172 switch (_op) {
173 case LT: return cmp > 0;
174 case LE: return cmp >= 0;
175 case GT: return cmp < 0;
176 case GE: return cmp <= 0;
177 }
178 }
179
180 ELException e = new ELException(L.l("can't compare {0} and {1}.",
181 aObj, bObj));
182
183 error(e, env);
184
185 return false;
186 }
187
188
191 @Override
192 public void printCreate(WriteStream os)
193 throws IOException
194 {
195 os.print("new com.caucho.el.CmpExpr(");
196 os.print(_op + ", ");
197 _left.printCreate(os);
198 os.print(", ");
199 _right.printCreate(os);
200 os.print(")");
201 }
202
203
206 public boolean equals(Object o)
207 {
208 if (! (o instanceof CmpExpr))
209 return false;
210
211 CmpExpr expr = (CmpExpr) o;
212
213 return (_op == expr._op &&
214 _left.equals(expr._left) &&
215 _right.equals(expr._right));
216 }
217
218
221 public String toString()
222 {
223 String op;
224
225 switch (_op) {
226 case LT:
227 op = " lt";
228 break;
229 case LE:
230 op = " le ";
231 break;
232 case GT:
233 op = " gt ";
234 break;
235 case GE:
236 op = " ge ";
237 break;
238 default:
239 op = " unknown(" + _op + ") ";
240 break;
241 }
242
243 return "(" + _left + op + _right + ")";
244 }
245 }
246 |
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