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34 package smallsql.database;
35
36 import java.util.Arrays  ;
37
38
39
42 public class ExpressionFunctionConvert extends ExpressionFunction {
43
44 final private Column datatype;
45
46 public ExpressionFunctionConvert(Column datatype, Expression value, Expression style) {
47 super();
48 this.datatype = datatype;
49 Expression[] params = (style == null) ? new Expression[]{value} : new Expression[]{value, style};
50 setParams( params );
51 }
52
53
54 int getFunction() {
55 return SQLTokenizer.CONVERT;
56 }
57
58
59 boolean isNull() throws Exception {
60 return param1.isNull();
61 }
62
63
64 boolean getBoolean() throws Exception {
65 return ExpressionValue.getBoolean( getObject(), getDataType() );
66 }
67
68
69 int getInt() throws Exception {
70 return ExpressionValue.getInt( getObject(), getDataType() );
71 }
72
73
74 long getLong() throws Exception {
75 return ExpressionValue.getLong( getObject(), getDataType() );
76 }
77
78
79 float getFloat() throws Exception {
80 return ExpressionValue.getFloat( getObject(), getDataType() );
81 }
82
83
84 double getDouble() throws Exception {
85 return ExpressionValue.getDouble( getObject(), getDataType() );
86 }
87
88
89 long getMoney() throws Exception {
90 return ExpressionValue.getMoney(getObject(), getDataType());
91 }
92
93
94 MutableNumeric getNumeric() throws Exception {
95 return ExpressionValue.getNumeric(getObject(), getDataType());
96 }
97
98
99 String getString() throws Exception {
100 Object obj = getObject();
101 if(obj == null) return null;
102 switch(datatype.getDataType()){
103 case SQLTokenizer.BIT:
104 return ((Boolean )obj).booleanValue() ? "1" : "0";
105 }
106 return obj.toString();
107 }
108
109
110 Object getObject() throws Exception {
111 if(param1.isNull()) return null;
112 final int dataType = getDataType();
113 switch(dataType){
114 case SQLTokenizer.LONGVARCHAR:
115 return convertToString();
116 case SQLTokenizer.VARCHAR:{
117 String str = convertToString();
118 int length = datatype.getDisplaySize();
119 if(length > str.length())
120 return str;
121 return str.substring(0,length);
122 }
123 case SQLTokenizer.CHAR:{
124 String str = convertToString();
125 int length = datatype.getDisplaySize();
126 if(length > str.length()){
127 char[] buffer = new char[length-str.length()];
128 Arrays.fill(buffer, ' ');
129 return str + new String (buffer);
130 }
131 return str.substring(0,length);
132 }
133 case SQLTokenizer.LONGVARBINARY:
134 return param1.getBytes();
135 case SQLTokenizer.VARBINARY:{
136 byte[] bytes = param1.getBytes();
137 int length = datatype.getPrecision();
138 if(length < bytes.length){
139 byte[] buffer = new byte[length];
140 System.arraycopy(bytes, 0, buffer, 0, Math.min(bytes.length,length) );
141 return buffer;
142 }
143 return bytes;
144
145 }
146 case SQLTokenizer.BINARY:{
147 byte[] bytes = param1.getBytes();
148 int length = datatype.getPrecision();
149 if(length != bytes.length){
150 byte[] buffer = new byte[length];
151 System.arraycopy(bytes, 0, buffer, 0, Math.min(bytes.length,length) );
152 return buffer;
153 }
154 return bytes;
155
156 }
157 case SQLTokenizer.BOOLEAN:
158 case SQLTokenizer.BIT:
159 return param1.getBoolean() ? Boolean.TRUE : Boolean.FALSE;
160 case SQLTokenizer.TINYINT:
161 return Utils.getInteger(param1.getInt() & 0xFF);
162 case SQLTokenizer.SMALLINT:
163 return Utils.getInteger((short)param1.getInt());
164 case SQLTokenizer.INT:
165 return Utils.getInteger(param1.getInt());
166 case SQLTokenizer.BIGINT:
167 return new Long (param1.getLong());
168 case SQLTokenizer.REAL:
169 return new Float (param1.getFloat());
170 case SQLTokenizer.FLOAT:
171 case SQLTokenizer.DOUBLE:
172 return new Double (param1.getDouble());
173 case SQLTokenizer.DATE:
174 case SQLTokenizer.TIME:
175 case SQLTokenizer.TIMESTAMP:
176 case SQLTokenizer.SMALLDATETIME:
177 return new DateTime( getDateTimeLong(), dataType );
178 case SQLTokenizer.NUMERIC:
179 case SQLTokenizer.DECIMAL:
180 MutableNumeric num = param1.getNumeric();
181 if(num != null && (dataType == SQLTokenizer.NUMERIC || dataType == SQLTokenizer.DECIMAL))
182 num.setScale(getScale());
183 return num;
184 case SQLTokenizer.MONEY:
185 case SQLTokenizer.SMALLMONEY:
186 return Money.createFromUnscaledValue(param1.getMoney());
187 case SQLTokenizer.UNIQUEIDENTIFIER:
188 switch(param1.getDataType()){
189 case SQLTokenizer.VARCHAR:
190 case SQLTokenizer.CHAR:
191 case SQLTokenizer.LONGVARCHAR:
192 case SQLTokenizer.CLOB:
193 return Utils.bytes2unique( Utils.unique2bytes(param1.getString()), 0);
194 }
195 return Utils.bytes2unique(param1.getBytes(), 0);
196 }
197 throw Utils.createSQLException("Unsupported type for CONVERT function:"+SQLTokenizer.getKeyWord(dataType));
198 }
199
200
201 final private String convertToString() throws Exception {
202 if(param2 != null){
203 int type = param1.getDataType();
204 switch(type){
205 case SQLTokenizer.SMALLDATETIME:
206 type = SQLTokenizer.TIMESTAMP;
207 case SQLTokenizer.TIMESTAMP:
208 case SQLTokenizer.DATE:
209 case SQLTokenizer.TIME:
210 return new DateTime( param1.getLong(), type ).toString(param2.getInt());
211 default:
212 return param1.getString();
213 }
214 }else
216 return param1.getString();
217 }
218
219
220 final private long getDateTimeLong() throws Exception {
221 switch(param1.getDataType()){
223 case SQLTokenizer.LONGVARCHAR:
224 case SQLTokenizer.VARCHAR:
225 case SQLTokenizer.CHAR:
226 return DateTime.parse( param1.getString() );
227 }
228 return param1.getLong();
230 }
231
232
233 final int getDataType() {
234 return datatype.getDataType();
235 }
236
237
238 final int getPrecision(){
239 final int dataType = getDataType();
240 switch(dataType){
241 case SQLTokenizer.VARCHAR:
242 case SQLTokenizer.VARBINARY:
243 case SQLTokenizer.BINARY:
244 case SQLTokenizer.CHAR:
245 case SQLTokenizer.NUMERIC:
246 case SQLTokenizer.DECIMAL:
247 return datatype.getPrecision();
248 default:
249 return super.getPrecision();
250 }
251 }
252
253
254 final int getScale() {
255 return datatype.getScale();
256 }
257
258
259 }
260 |
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