October 27, 2011, 17:32
In order to release your app in the Android market place you need to digitally sign it. The instructions are here. But in short I will show you what you need from the command line, you won’t have to read all the instructions. First off make your app .apk name something different then what your going to use in the end. As the process requires the input and output to have different file names.
Lets take a look, this example is from DOS command line
Create the signature key
C:\Temp> keytool -genkey -v -keystore c:\temp\release-key.keystore -alias MyAlias -keyalg RSA -keysize 2048 -validity 10000
Sign using the key
C:\Temp> jarsigner -verbose -keystore release-key.keystore release.MyApp.apk MyAlias
Verify that it took
C:\Temp> jarsigner -verify -verbose release.MyApp.apk
Run the align tool as recommended
C:\Temp> zipalign -v 4 release.MyApp.apk MyApp.apk
And your all done, now publish it and start watching the downloads.
October 6, 2011, 15:12
I had to setup Postgres on my linux box, configure and make sure it was working. Since that was the case I started the install, then wrote a very simple Java program to connect and retrieve some data from one of the database tables. The install is simple and pretty easy to google. Once your Postrgres database is up and running you should be able to connect to it. You will need a java Postgres database driver, the one I downloaded was the postgresql-9.1-901.jdbc4.jar then add the jar to your project. And finally to make sure your database is accessible from a program you can use the sample below.
//
import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;
// Simple test class to prove connection to Postgres database
public class Main
{
public Main()
{ super(); }
public static void main(String[] args)
{
System.out.println(” Postgres Test”);
Connection myConn = null;
try
{
// The driver
Class.forName(“org.postgresql.Driver”);
System.out.println(“PostgreSQL JDBC Driver Registered!”);
myConn = DriverManager.getConnection( “jdbc:postgresql://127.0.0.1:5432/testDb”,
“testUser”, “myPassword” );
// Connected ?
if (myConn != null)
System.out.println(“Successfully connected to Postgres Database”);
// Get data from the database
Statement stGetCount = myConn.createStatement();
ResultSet rs = stGetCount.executeQuery(“SELECT * from cars”);
while( rs.next() )
{
System.out.println(“result=” + rs.getString(1) + “,” + rs.getString(2) + “,” + rs.getString(3) );
}
}
catch( Exception ex )
{
ex.printStackTrace();
}
finally
{
try{myConn.close();}catch(Exception IDontCare ){}
}
}
} // EOC