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1 package com.quadcap.app.dbimage;
2
3
40
41 import java.io.ByteArrayOutputStream  ;
42 import java.io.IOException ;
43 import java.io.InputStream ;
44 import java.io.OutputStream ;
45
46 import java.util.Enumeration ;
47 import java.util.Properties ;
48
49 import java.sql.Connection ;
50 import java.sql.DatabaseMetaData ;
51 import java.sql.DriverManager ;
52 import java.sql.PreparedStatement ;
53 import java.sql.ResultSet ;
54 import java.sql.Statement ;
55 import java.sql.SQLException ;
56
57 import javax.servlet.ServletConfig ;
58 import javax.servlet.ServletException ;
59
60 import javax.servlet.http.HttpServlet ;
61 import javax.servlet.http.HttpServletRequest ;
62 import javax.servlet.http.HttpServletResponse ;
63
64 import java.awt.Image ;
66 import java.awt.Graphics2D ;
67 import java.awt.geom.AffineTransform ;
68 import java.awt.image.BufferedImage ;
69 import java.io.IOException ;
70 import java.io.OutputStream ;
71 import java.io.FileOutputStream ;
72 import javax.swing.ImageIcon ;
73 import com.sun.image.codec.jpeg.JPEGCodec;
74 import com.sun.image.codec.jpeg.JPEGImageEncoder;
75
76
81 public class DbImageServlet extends HttpServlet {
82 String url = null;
83
84 public void init(ServletConfig config) throws ServletException {
85 super.init(config);
86 try {
87 url = config.getInitParameter("jdbc.url");
88 if (url == null) {
89 throw new ServletException ("No jdbc.url property");
90 } else {
91 String driver = "com.quadcap.jdbc.JdbcDriver";
92 String d = config.getInitParameter("jdbc.driver");
93 if (d != null) driver = d;
94 Class.forName(driver);
95 }
96 config.getServletContext().setAttribute("servlet", this);
97
98 Connection conn = getConnection();
99 Statement stmt = conn.createStatement();
100 try {
101 DatabaseMetaData dbmeta = conn.getMetaData();
102 ResultSet rs = dbmeta.getTables(null, null, "images", null);
103 if (!rs.next()) {
104 stmt.execute(
105 "create table images(" +
106 " name varchar(99999), " +
107 " maxDim int, " +
108 " data blob," +
109 " size int)");
110 stmt.execute(
111 "create unique index images1 on images(name, maxDim)");
112 }
113 rs.close();
114 } finally {
115 stmt.close();
116 conn.close();
117 }
118
119 } catch (Exception e) {
120 e.printStackTrace(System.err);
121 throw new ServletException (e);
122 }
123 }
124
125 public Connection getConnection() throws SQLException {
126 Properties p = new Properties ();
127 p.put("create", "true");
128 return DriverManager.getConnection(url, p);
129 }
130
131 byte[] resizeImage(byte[] imageBytes, int maxDim) throws IOException {
132 ImageIcon inImage = new ImageIcon (imageBytes);
133
134 double scale = (double)maxDim/(double)inImage.getIconHeight();
136
137 if (inImage.getIconWidth() > inImage.getIconHeight()) {
138 scale = (double)maxDim/(double)inImage.getIconWidth();
139 }
140
141 int scaledW = (int)(scale*inImage.getIconWidth());
144 int scaledH = (int)(scale*inImage.getIconHeight());
145
146 BufferedImage outImage = new BufferedImage (scaledW, scaledH,
148 BufferedImage.TYPE_INT_RGB);
149
150 AffineTransform tx = new AffineTransform ();
152
153 if (scale < 1.0d) {
156 tx.scale(scale, scale);
157 }
158
159 Graphics2D g2d = outImage.createGraphics();
161 g2d.drawImage(inImage.getImage(), tx, null);
162 g2d.dispose();
163
164 ByteArrayOutputStream os = new ByteArrayOutputStream ();
166 JPEGImageEncoder encoder =
167 JPEGCodec.createJPEGEncoder(os);
168 encoder.encode(outImage);
169
170 return os.toByteArray();
171 }
172
173 void sendImage(byte[] image, HttpServletResponse response)
174 throws ServletException , IOException
175 {
176 OutputStream os = response.getOutputStream();
177 response.setContentLength(image.length);
178 os.write(image);
179 }
180
181 void storeImage(Connection conn, byte[] image, String name, int dim)
182 throws SQLException
183 {
184 PreparedStatement p = conn.prepareStatement(
185 "insert into images(?,?,?,?)");
186 p.clearParameters();
187 p.setString(1, name);
188 p.setInt(2, image.length);
189 p.setBytes(3, image);
190 p.setInt(4, dim);
191 p.executeUpdate();
192 p.close();
193 }
194
195 public void doGet(HttpServletRequest request,
196 HttpServletResponse response)
197 throws ServletException
198 {
199 String s = request.getServletPath();
200 response.setContentType(getServletContext().getMimeType(s));
201 Connection conn;
202 try {
203 conn = getConnection();
204 } catch (SQLException ex) {
205 throw new ServletException (ex);
206 }
207 int dim = -1;
208 String mdim = request.getParameter("maxDim");
209 if (mdim != null) {
210 dim = Integer.parseInt(mdim);
211 }
212 try {
213 Statement stmt = conn.createStatement();
214 if (dim <= 0) {
215 ResultSet rs = stmt.executeQuery(
216 "select data from images where name = '" + s +
217 "' and maxDim <= 0");
218 if (rs.next()) {
219 byte[] image = rs.getBytes(1);
220 rs.close();
221 sendImage(image, response);
222 } else {
223 rs.close();
224 }
226 } else {
227 ResultSet rs = stmt.executeQuery(
228 "select data from images where name ='" + s +
229 "' and maxDim = " + dim);
230 if (rs.next()) {
231 byte[] image = rs.getBytes(1);
232 rs.close();
233 sendImage(image, response);
234 } else {
235 rs.close();
236 rs = stmt.executeQuery(
237 "select data, size from images where name = '" + s +
238 "' and maxDim <= 0");
239 if (rs.next()) {
240 byte[] image = rs.getBytes(1);
241 rs.close();
242 byte[] resized = resizeImage(image, dim);
243 storeImage(conn, resized, s, dim);
244 sendImage(resized, response);
245 } else {
246 rs.close();
248 }
249 }
250 }
251 } catch (Throwable t) {
252 throw new ServletException (t);
253 } finally {
254 try {
255 conn.close();
256 } catch (Throwable t) {
257 throw new ServletException (t);
258 }
259 }
260 }
261
262 }
263 |
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