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34 package smallsql.database;
35
36
37
40 final class ExpressionFunctionCase extends Expression {
41
42
45 ExpressionFunctionCase() {
46 super(FUNCTION);
47 }
48
49
50 private final Expressions cases = new Expressions();
51 private final Expressions results = new Expressions();
52 private Expression elseResult = Expression.NULL;
53 private int dataType = -1;
54
55
56 final void addCase(Expression condition, Expression result){
57 cases.add(condition);
58 results.add(result);
59 }
60
61
62 final void setElseResult(Expression expr){
63 elseResult = expr;
64 }
65
66
67
70 final void setEnd(){
71 Expression[] params = new Expression[cases.size()*2 + (elseResult!=null ? 1 : 0)];
72 int i=0;
73 for(int p=0; p<cases.size(); p++){
74 params[i++] = cases .get( p );
75 params[i++] = results.get( p );
76 }
77 if(i<params.length)
78 params[i] = elseResult;
79 super.setParams(params);
80 }
81
82 final void setParams( Expression[] params ){
83 super.setParams(params);
84 int i = 0;
85 for(int p=0; p<cases.size(); p++){
86 cases .set( p, params[i++]);
87 results.set( p, params[i++]);
88 }
89 if(i<params.length)
90 elseResult = params[i];
91 }
92
93
94 void setParamAt( Expression param, int idx){
95 super.setParamAt( param, idx );
96 int p = idx / 2;
97 if(p>=cases.size()){
98 elseResult = param;
99 return;
100 }
101 if(idx % 2 > 0){
102 results.set( p, param );
103 }else{
104 cases.set( p, param );
105 }
106 }
107
108
109
113
114 final int getFunction() {
115 return SQLTokenizer.CASE;
116 }
117
118
119 final boolean isNull() throws Exception  {
120 return getResult().isNull();
121 }
122
123
124 final boolean getBoolean() throws Exception {
125 return getResult().getBoolean();
126 }
127
128
129 final int getInt() throws Exception {
130 return getResult().getInt();
131 }
132
133
134 final long getLong() throws Exception {
135 return getResult().getLong();
136 }
137
138
139 final float getFloat() throws Exception {
140 return getResult().getFloat();
141 }
142
143
144 final double getDouble() throws Exception {
145 return getResult().getDouble();
146 }
147
148
149 final long getMoney() throws Exception {
150 return getResult().getMoney();
151 }
152
153
154 final MutableNumeric getNumeric() throws Exception {
155 return getResult().getNumeric();
156 }
157
158
159 final Object getObject() throws Exception {
160 return getResult().getObject();
161 }
162
163
164 final String getString() throws Exception {
165 return getResult().getString();
166 }
167
168
169 final byte[] getBytes() throws Exception {
170 return getResult().getBytes();
171 }
172
173
174 final int getDataType() {
175 if(dataType < 0){
176 dataType = elseResult.getDataType();
177 for(int i=0; i<results.size(); i++){
178 dataType = ExpressionArithmetic.getDataType(dataType, results.get(i).getDataType());
179 }
180 }
181 return dataType;
182 }
183
184
185 final int getPrecision(){
186 int precision = 0;
187 for(int i=results.size()-1; i>=0; i--){
188 precision = Math.max(precision, results.get(i).getPrecision());
189 }
190 return precision;
191 }
192
193
194 final int getScale(){
195 int precision = 0;
196 for(int i=results.size()-1; i>=0; i--){
197 precision = Math.max(precision, results.get(i).getScale());
198 }
199 return precision;
200 }
201
202
203
207
208 final private Expression getResult() throws Exception {
209 for(int i=0; i<cases.size(); i++){
210 if(cases.get(i).getBoolean()) return results.get(i);
211 }
212 return elseResult;
213 }
214
215 }
216 |
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