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    <blockquote> <p>a) What type of field should I put in the database? (e.g VARCHAR)</p> </blockquote> <p>An image is binary data. Just use a binary field. In PostgreSQL it's <a href="http://www.postgresql.org/docs/8.4/static/datatype-binary.html" rel="nofollow noreferrer"><code>bytea</code></a>.</p> <blockquote> <p>b) What type of object should I use for storing and manipulating the image (at an object layer)? (e.g java.awt.Image)</p> </blockquote> <p>Use an <a href="http://docs.oracle.com/javase/6/docs/api/java/io/InputStream.html" rel="nofollow noreferrer"><code>InputStream</code></a> or <code>byte[]</code> to store it. The Java 2D API has classes/methods which can take/return either of those types.</p> <blockquote> <p>c) How do I create an object of the type selected (answer of question b) from the data obtained from the database?</p> </blockquote> <p>Use <a href="http://docs.oracle.com/javase/6/docs/api/java/sql/ResultSet.html#getBinaryStream%28java.lang.String%29" rel="nofollow noreferrer"><code>ResultSet#getBinaryStream()</code></a> to get an <code>InputStream</code> of it or <a href="http://docs.oracle.com/javase/6/docs/api/java/sql/ResultSet.html#getBytes%28java.lang.String%29" rel="nofollow noreferrer"><code>ResultSet#getBytes()</code></a> to get a <code>byte[]</code> of it.</p> <blockquote> <p>d) How do I save an object of the type selected (answer of question b) to the database?</p> </blockquote> <p>Use <a href="http://docs.oracle.com/javase/6/docs/api/java/sql/PreparedStatement.html#setBinaryStream%28int,%20java.io.InputStream%29" rel="nofollow noreferrer"><code>PreparedStatement#setBinaryStream()</code></a> or <a href="http://docs.oracle.com/javase/6/docs/api/java/sql/PreparedStatement.html#setBytes%28int,%20byte[]%29" rel="nofollow noreferrer"><code>PreparedStatement#setBytes()</code></a>. Note: if you're new to JDBC/<code>PreparedStatement</code> as well, then I recommend you to get yourself through the <a href="http://docs.oracle.com/javase/tutorial/jdbc/basics/index.html" rel="nofollow noreferrer">Sun basic JDBC tutorial</a>.</p> <blockquote> <p>e) How do I draw the image on a web page?</p> </blockquote> <p>Use a HTML <code>&lt;img&gt;</code> element whose <code>src</code> points to an URL matching the <code>url-pattern</code> of a <code>Servlet</code>. You can pass the image identifier as request parameter or pathinfo. Inside the <code>Servlet</code> you just write the obtained <code>InputStream</code> to the <code>OutputStream</code> of the response the usual Java IO way. You can find a code example in <a href="https://stackoverflow.com/questions/2340406/retrieve-multiple-images-from-mysql/2341322#2341322">this answer</a> I posted some time ago.</p> <hr> <p>That said, storing <em>only</em> raw images in a database is generally not a good idea. You should preferably also store some metadata along it, such as the <a href="http://www.iana.org/assignments/media-types" rel="nofollow noreferrer">content type</a> (e.g. <code>image/jpeg</code>, <code>image/gif</code>, etc) which you after all need in the response header so that the browser knows what to do with it.</p>
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    1. POHow to save, retrieve and draw an image in webapplication using Java and PostgreSQL?
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    1. COBrilliant answer. Very thorough
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    2. COWell Explained... Thanks
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