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1
21
22 package nu.xom.samples;
23
24 import nu.xom.*;
25 import java.sql.*;
26 import java.io.*;
27
28
29
37 public class DatabaseBuilder {
38
39 private Connection connection;
40
41
42 public DatabaseBuilder(String  jdbcURL) throws SQLException {
50 connection = DriverManager.getConnection(jdbcURL);
51 }
52
53
54 public Document build(String selectQuery)
55 throws SQLException, ParsingException {
56
57 Statement statement = connection.createStatement();
58 ResultSet data = statement.executeQuery(selectQuery);
59 ResultSetMetaData metadata = data.getMetaData();
60 int numFields = metadata.getColumnCount();
61
62 Element table = new Element("table");
63
64 while (data.next()) {
65 Element record = new Element("record");
66 for (int field = 1; field <= numFields; field++) {
67 Element fieldElement = new Element("field");
68 int type = metadata.getColumnType(field);
69 String typeName = getSchemaType(type);
70 Attribute typeAtt = new Attribute("xsi:type",
71 "http://www.w3.org/2001/XMLSchema-instance", typeName);
72 fieldElement.addAttribute(typeAtt);
73 String name = metadata.getColumnName(field);
74 Attribute nameAtt = new Attribute("name", name);
75 fieldElement.addAttribute(nameAtt);
76 Object value = data.getObject(field);
78 if (value == null) { Attribute nilAtt = new Attribute("xsi:nil",
80 "http://www.w3.org/2001/XMLSchema-instance", "true");
81 fieldElement.addAttribute(nilAtt);
82 }
83 else { fieldElement.appendChild(convertToXML(data, field, type));
85 }
86 record.appendChild(fieldElement);
87 }
88 table.appendChild(record);
89 }
90 statement.close();
91
92 table.addNamespaceDeclaration("xsi",
93 "http://www.w3.org/2001/XMLSchema-instance");
94 table.addNamespaceDeclaration("xsd", "http://www.w3.org/2001/XMLSchema");
95 return new Document(table);
96
97 }
98
99
100 private Node convertToXML(ResultSet data, int field, int type)
104 throws SQLException, ParsingException {
105
106 switch (type) {
107 case Types.BINARY:
108 case Types.VARBINARY:
109 case Types.LONGVARBINARY:
110 return hexEncode(data.getBinaryStream(field));
111 case Types.BLOB:
112 Blob blob = data.getBlob(field);
113 return hexEncode(blob.getBinaryStream());
114 case Types.CLOB:
115 Clob clob = data.getClob(field);
116 Reader r = clob.getCharacterStream();
117 char[] text = new char[1024];
118 int numRead;
119 try {
120 StringBuffer result = new StringBuffer ();
121 while ((numRead = r.read(text, 0, 1024)) != -1) {
122 result.append(escapeText(text, 0, numRead));
123 }
124 return new Text(result.toString());
125 }
126 catch (IOException ex) {
127 throw new ParsingException("Read from CLOB failed", ex);
128 }
129 case Types.ARRAY:
130 Array array = data.getArray(field);
131 return writeArray(array);
132 default: Object o = data.getObject(field);
134 if (o == null) return new Text("");
135 String s = o.toString();
136 char[] value = s.toCharArray();
137 return escapeText(value, 0, value.length);
138 }
139
140 }
141
142
143 private Text hexEncode(InputStream in) {
144
145 StringBuffer result = new StringBuffer ();
146 try {
147 int octet;
148 while ((octet = in.read()) != -1) {
149 StringWriter out = new StringWriter(2);
150 if (octet < 16) out.write('0');
151 out.write(Integer.toHexString(octet));
152 result.append(out.toString());
153 }
154 return new Text(result.toString());
155 }
156 catch (IOException ex) {
157 throw new XMLException("Error while hex-encoding", ex);
158 }
159
160 }
161
162
163 private Text escapeText(char[] text, int start, int length) {
167 StringBuffer result = new StringBuffer (length);
168 for (int i = start; i < length; i++) {
169 result.append(escapeChar(text[i]));
170 }
171 return new Text(result.toString());
172 }
173
174 private char escapeChar(char c) {
175 if (c >= 0x20) return c;
176 else if (c == '\n') return c;
177 else if (c == '\r') return c;
178 else if (c == '\t') return c;
179 return '\uFFFD';
180 }
181
182 private Node writeArray(Array array)
183 throws SQLException, ParsingException {
184
185 ResultSet data = array.getResultSet();
186 int type = array.getBaseType();
187 String typeName = getSchemaType(type);
188
189 Element arrayElement = new Element("array");
190 while (data.next()) {
191 Element component = new Element("component");
192 component.addAttribute(new Attribute("xsi:type",
193 "http://www.w3.org/2001/XMLSchema-instance",
194 typeName));
195 component.appendChild(convertToXML(data, 2, type));
196 arrayElement.appendChild(component);
197 }
198 return arrayElement;
199 }
200
201
202 public static String getSchemaType(int type) {
203
204 switch (type) {
205 case Types.ARRAY: return "array";
206 case Types.BIGINT: return "xsd:long";
207 case Types.BINARY: return "xsd:hexBinary";
208 case Types.BIT: return "xsd:boolean";
209 case Types.BLOB: return "xsd:hexBinary";
210 case Types.CHAR: return "xsd:string";
211 case Types.CLOB: return "xsd:string";
212 case Types.DATE: return "xsd:date";
213 case Types.DECIMAL: return "xsd:decimal";
214 case Types.DOUBLE: return "xsd:double";
215 case Types.FLOAT: return "xsd:decimal";
216 case Types.INTEGER: return "xsd:int";
217 case Types.JAVA_OBJECT: return "xsd:string";
218 case Types.LONGVARBINARY: return "xsd:hexBinary";
219 case Types.LONGVARCHAR: return "xsd:string";
220 case Types.NUMERIC: return "xsd:decimal";
221 case Types.REAL: return "xsd:float";
222 case Types.REF: return "xsd:IDREF";
223 case Types.SMALLINT: return "xsd:short";
224 case Types.STRUCT: return "struct";
225 case Types.TIME: return "xsd:time";
226 case Types.TIMESTAMP: return "xsd:dateTime";
227 case Types.TINYINT: return "xsd:byte";
228 case Types.VARBINARY: return "xsd:hexBinary";
229 default: return "xsd:string";
231 }
232
233 }
234
235
236 public static void main(String [] args) {
237
238 if (args.length < 2) {
239 System.out.println(
240 "Usage: java DatabaseBuilder URL query driverClass");
241 return;
242 }
243 String url = args[0];
244 String query = args[1];
245 String driverClass = "org.gjt.mm.mysql.Driver"; if (args.length >= 3) driverClass = args[2];
247
248 try {
249 Class.forName(driverClass).newInstance();
251
255 DatabaseBuilder builder = new DatabaseBuilder(url);
256 Serializer out = new Serializer(System.out);
257
258 out.setIndent(2);
259 Document doc = builder.build(query);
260 out.write(doc);
261 out.flush();
262 }
263 catch (InstantiationException ex) {
264 System.out.println(driverClass + " could not be instantiated");
265 }
266 catch (ClassNotFoundException ex) {
267 System.out.println(driverClass + " could not be found");
268 }
269 catch (Exception ex) { ex.printStackTrace();
271 }
272
273 }
274
275 }
276 |
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