provide a java console app example

git-svn-id: http://svn.osgeo.org/postgis/trunk@8590 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/doc/using_raster_dataman.xml b/doc/using_raster_dataman.xml
index 6c65f3bc1d2b56812d9e008c769a55aaa6135b5f..d02e1790947c20bf78b341e7062ccccb98d1759b 100644 (file)
--- a/doc/using_raster_dataman.xml
+++ b/doc/using_raster_dataman.xml
@@ -608,6 +608,91 @@ public class TestRaster : IHttpHandler
         }
                return result;
        }
+}]]></programlisting>
+               </sect2>
+               <sect2 id="RT_Java_Console_App">
+                       <title>Java console app that outputs raster query as PNG file</title>
+                       <para>In this section, we'll demonstrate how to use PostgreSQL JDBC driver and the <xref linkend="RT_ST_AsGDALRaster" /> family of functions to
+                               output band 1,2,3 of a raster to a file.</para>
+                               
+                       <para>The sample query demonstrates how to combine a whole bunch of raster functions together to grab all tiles that intersect
+                               a particular wgs 84 bounding box and then unions with <xref linkend="RT_ST_Union" /> the intersecting tiles together returning all bands, transforms to user specified projection using <xref linkend="RT_ST_Transform" />,
+                               and then outputs the results as a png using <xref linkend="RT_ST_AsPNG" />.</para>
+                               <para>This is same example as <xref linkend="RT_PHP_Output" /> except implemented in C#.</para>
+                               <para>You would call the below using <programlisting>java -jar SaveQueryImage.jar "2249"</programlisting> to get the raster image in Massachusetts state plane feet in a file in the same folder.  The file will be called <varname>test.png</varname></para>
+                               <para>You can compile the following code using a command something like:
+<programlisting>set env CLASSPATH .:..\postgresql-9.0-801.jdbc4.jar
+javac SaveQueryImage.java
+jar cfm SaveQueryImage.jar Manifest.txt *.class</programlisting>
+                               <programlisting> -- Manifest.txt --
+<![CDATA[Class-Path: postgresql-9.0-801.jdbc4.jar
+Main-Class: SaveQueryImage]]></programlisting>
+                       <programlisting>// Code for SaveQueryImage.java
+<![CDATA[import java.sql.Connection;
+import java.sql.SQLException;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.io.*;
+
+public class SaveQueryImage {
+  public static void main(String[] argv) {
+      System.out.println("Checking if Driver is registered with DriverManager.");
+      
+      try {
+        //java.sql.DriverManager.registerDriver (new org.postgresql.Driver());
+        Class.forName("org.postgresql.Driver");
+      } 
+      catch (ClassNotFoundException cnfe) {
+        System.out.println("Couldn't find the driver!");
+        cnfe.printStackTrace();
+        System.exit(1);
+      }
+      
+      Connection conn = null;
+         int srid = 26986;
+      
+      try {
+        conn = DriverManager.getConnection("jdbc:postgresql://localhost:5432/mydb","myuser", "mypwd");
+        conn.setAutoCommit(false);
+
+        PreparedStatement sGetImg = conn.prepareStatement("SELECT ST_AsPNG( " +
+                       " ST_Transform( " + 
+                          "  ST_AddBand(ST_Union(rast,1), ARRAY[ST_Union(rast,2),ST_Union(rast,3)]) " +
+                       "       ,?) ) As new_rast " +
+                       " FROM aerials.boston " +  
+                       " WHERE " + 
+                       " ST_Intersects(rast, ST_Transform(ST_MakeEnvelope(-71.1217, 42.227, -71.1210, 42.218,4326),26986) );");
+               if (argv.length > 0) {
+                       srid = Integer.parseInt(argv[0]);
+               }
+        sGetImg.setInt(1, srid);
+        
+        ResultSet rs = sGetImg.executeQuery();
+               
+               FileOutputStream fout;
+               try
+               {
+                       rs.next();
+                       fout = new FileOutputStream(new File("test.png") );
+                       fout.write(rs.getBytes(1));
+                       fout.close();
+               }
+               catch(Exception e)
+               {
+                       System.out.println("Can't create file");
+                       e.printStackTrace();
+               }
+               
+        rs.close();
+               sGetImg.close();
+        conn.close();
+      } 
+      catch (SQLException se) {
+        System.out.println("Couldn't connect: print out a stack trace and exit.");
+        se.printStackTrace();
+        System.exit(1);
+      }   
+  }
 }]]></programlisting>
                </sect2>
    </sect1>