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1
18 package org.apache.activemq.filter;
19
20 import java.math.BigDecimal  ;
21
22 import javax.jms.JMSException ;
23
24
29 public class ConstantExpression implements Expression {
30
31 static class BooleanConstantExpression extends ConstantExpression implements BooleanExpression {
32 public BooleanConstantExpression(Object value) {
33 super(value);
34 }
35 public boolean matches(MessageEvaluationContext message) throws JMSException {
36 Object object = evaluate(message);
37 return object!=null && object==Boolean.TRUE;
38 }
39 }
40
41 public static final BooleanConstantExpression NULL = new BooleanConstantExpression(null);
42 public static final BooleanConstantExpression TRUE = new BooleanConstantExpression(Boolean.TRUE);
43 public static final BooleanConstantExpression FALSE = new BooleanConstantExpression(Boolean.FALSE);
44
45 private Object value;
46
47 public static ConstantExpression createFromDecimal(String text) {
48
49 if( text.endsWith("l") || text.endsWith("L") )
51 text = text.substring(0, text.length()-1);
52
53 Number value;
54 try {
55 value = new Long (text);
56 } catch ( NumberFormatException e) {
57 value = new BigDecimal (text);
59 }
60
61 long l = value.longValue();
62 if (Integer.MIN_VALUE <= l && l <= Integer.MAX_VALUE) {
63 value = new Integer (value.intValue());
64 }
65 return new ConstantExpression(value);
66 }
67
68 public static ConstantExpression createFromHex(String text) {
69 Number value = new Long (Long.parseLong(text.substring(2), 16));
70 long l = value.longValue();
71 if (Integer.MIN_VALUE <= l && l <= Integer.MAX_VALUE) {
72 value = new Integer (value.intValue());
73 }
74 return new ConstantExpression(value);
75 }
76
77 public static ConstantExpression createFromOctal(String text) {
78 Number value = new Long (Long.parseLong(text, 8));
79 long l = value.longValue();
80 if (Integer.MIN_VALUE <= l && l <= Integer.MAX_VALUE) {
81 value = new Integer (value.intValue());
82 }
83 return new ConstantExpression(value);
84 }
85
86 public static ConstantExpression createFloat(String text) {
87 Number value = new Double (text);
88 return new ConstantExpression(value);
89 }
90
91 public ConstantExpression(Object value) {
92 this.value = value;
93 }
94
95 public Object evaluate(MessageEvaluationContext message) throws JMSException {
96 return value;
97 }
98
99 public Object getValue() {
100 return value;
101 }
102
103
106 public String toString() {
107 if (value == null) {
108 return "NULL";
109 }
110 if (value instanceof Boolean ) {
111 return ((Boolean ) value).booleanValue() ? "TRUE" : "FALSE";
112 }
113 if (value instanceof String ) {
114 return encodeString((String ) value);
115 }
116 return value.toString();
117 }
118
119
124 public int hashCode() {
125 return toString().hashCode();
126 }
127
128
133 public boolean equals(Object o) {
134
135 if (o == null || !this.getClass().equals(o.getClass())) {
136 return false;
137 }
138 return toString().equals(o.toString());
139
140 }
141
142
143
150 public static String encodeString(String s) {
151 StringBuffer b = new StringBuffer ();
152 b.append('\'');
153 for (int i = 0; i < s.length(); i++) {
154 char c = s.charAt(i);
155 if (c == '\'') {
156 b.append(c);
157 }
158 b.append(c);
159 }
160 b.append('\'');
161 return b.toString();
162 }
163
164 }
165 |
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