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1
18 package org.apache.activemq.filter;
19
20 import java.math.BigDecimal  ;
21 import java.util.Collection ;
22 import java.util.HashSet ;
23 import java.util.Iterator ;
24 import java.util.List ;
25
26 import javax.jms.JMSException ;
27
28
33 public abstract class UnaryExpression implements Expression {
34
35 private static final BigDecimal BD_LONG_MIN_VALUE = BigDecimal.valueOf(Long.MIN_VALUE);
36 protected Expression right;
37
38 public static Expression createNegate(Expression left) {
39 return new UnaryExpression(left) {
40 public Object evaluate(MessageEvaluationContext message) throws JMSException {
41 Object rvalue = right.evaluate(message);
42 if (rvalue == null) {
43 return null;
44 }
45 if (rvalue instanceof Number ) {
46 return negate((Number ) rvalue);
47 }
48 return null;
49 }
50
51 public String getExpressionSymbol() {
52 return "-";
53 }
54 };
55 }
56
57 public static BooleanExpression createInExpression(PropertyExpression right, List elements, final boolean not) {
58
59 Collection t;
61 if( elements.size()==0 )
62 t=null;
63 else if( elements.size() < 5 )
64 t = elements;
65 else {
66 t = new HashSet (elements);
67 }
68 final Collection inList = t;
69
70 return new BooleanUnaryExpression(right) {
71 public Object evaluate(MessageEvaluationContext message) throws JMSException {
72
73 Object rvalue = right.evaluate(message);
74 if (rvalue == null) {
75 return null;
76 }
77 if( rvalue.getClass()!=String .class )
78 return null;
79
80 if( (inList!=null && inList.contains(rvalue)) ^ not ) {
81 return Boolean.TRUE;
82 } else {
83 return Boolean.FALSE;
84 }
85
86 }
87
88 public String toString() {
89 StringBuffer answer = new StringBuffer ();
90 answer.append(right);
91 answer.append(" ");
92 answer.append(getExpressionSymbol());
93 answer.append(" ( ");
94
95 int count=0;
96 for (Iterator i = inList.iterator(); i.hasNext();) {
97 Object o = (Object ) i.next();
98 if( count!=0 ) {
99 answer.append(", ");
100 }
101 answer.append(o);
102 count++;
103 }
104
105 answer.append(" )");
106 return answer.toString();
107 }
108
109 public String getExpressionSymbol() {
110 if( not )
111 return "NOT IN";
112 else
113 return "IN";
114 }
115 };
116 }
117
118 abstract static class BooleanUnaryExpression extends UnaryExpression implements BooleanExpression {
119 public BooleanUnaryExpression(Expression left) {
120 super(left);
121 }
122
123 public boolean matches(MessageEvaluationContext message) throws JMSException {
124 Object object = evaluate(message);
125 return object!=null && object==Boolean.TRUE;
126 }
127 };
128
129
130 public static BooleanExpression createNOT(BooleanExpression left) {
131 return new BooleanUnaryExpression(left) {
132 public Object evaluate(MessageEvaluationContext message) throws JMSException {
133 Boolean lvalue = (Boolean ) right.evaluate(message);
134 if (lvalue == null) {
135 return null;
136 }
137 return lvalue.booleanValue() ? Boolean.FALSE : Boolean.TRUE;
138 }
139
140 public String getExpressionSymbol() {
141 return "NOT";
142 }
143 };
144 }
145
146 public static BooleanExpression createXPath(final String xpath) {
147 return new XPathExpression(xpath);
148 }
149
150 public static BooleanExpression createXQuery(final String xpath) {
151 return new XQueryExpression(xpath);
152 }
153
154 public static BooleanExpression createBooleanCast(Expression left) {
155 return new BooleanUnaryExpression(left) {
156 public Object evaluate(MessageEvaluationContext message) throws JMSException {
157 Object rvalue = right.evaluate(message);
158 if (rvalue == null)
159 return null;
160 if (!rvalue.getClass().equals(Boolean .class))
161 return Boolean.FALSE;
162 return ((Boolean )rvalue).booleanValue() ? Boolean.TRUE : Boolean.FALSE;
163 }
164
165 public String toString() {
166 return right.toString();
167 }
168
169 public String getExpressionSymbol() {
170 return "";
171 }
172 };
173 }
174
175 private static Number negate(Number left) {
176 Class clazz = left.getClass();
177 if (clazz == Integer .class) {
178 return new Integer (-left.intValue());
179 }
180 else if (clazz == Long .class) {
181 return new Long (-left.longValue());
182 }
183 else if (clazz == Float .class) {
184 return new Float (-left.floatValue());
185 }
186 else if (clazz == Double .class) {
187 return new Double (-left.doubleValue());
188 }
189 else if (clazz == BigDecimal .class) {
190 BigDecimal bd = (BigDecimal )left;
195 bd = bd.negate();
196
197 if( BD_LONG_MIN_VALUE.compareTo(bd)==0 ) {
198 return new Long (Long.MIN_VALUE);
199 }
200 return bd;
201 }
202 else {
203 throw new RuntimeException ("Don't know how to negate: "+left);
204 }
205 }
206
207 public UnaryExpression(Expression left) {
208 this.right = left;
209 }
210
211 public Expression getRight() {
212 return right;
213 }
214
215 public void setRight(Expression expression) {
216 right = expression;
217 }
218
219
222 public String toString() {
223 return "(" + getExpressionSymbol() + " " + right.toString() + ")";
224 }
225
226
231 public int hashCode() {
232 return toString().hashCode();
233 }
234
235
240 public boolean equals(Object o) {
241
242 if (o == null || !this.getClass().equals(o.getClass())) {
243 return false;
244 }
245 return toString().equals(o.toString());
246
247 }
248
249
255 abstract public String getExpressionSymbol();
256
257 }
258 |
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