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Subject: Re: Is this a correct implementation of an abstract class and implementation class
Date: Sat, 12 Aug 2017 22:00:24 -0400
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On 8/12/2017 5:20 PM, Cecil Westerhof wrote:
> I want to write a layer around JDBC. For this I have an abstract class
> SQL in which I have the following constructor and abstract methods:
>      // ################ constructors
>      public SQL (String database) throws SQLException {
>          String forName   = getForName();
>          String sqlDriver = getSQLDriver();
> 
>          try {
>              Class.forName(forName);
>          } catch (ClassNotFoundException e) {
>              throw new SQLException("Could not find the class " + forName + ".");
>          }
>          conn = DriverManager.getConnection(sqlDriver + database);
>          this.database = database;
>      }
> 
>      // ################ abstract
>      abstract String getForName();
>      abstract String getSQLDriver();
> 
> 
> I have also an implementation class SQLite3 in which I have:
>      // ################ constructors
>      public SQLite3 (String database) throws SQLException {
>          super(database);
>      }
> 
>      // ################ default
>      @Override
>      String getForName() {
>          return "org.sqlite.JDBC";
>      }
> 
>      @Override
>      String getSQLDriver() {
>          return "jdbc:sqlite:";
>      }
> 
> Is this the correct way to do this, or is there a better way?

I have done something similar many times.

I like the approach.

:-)

I assume you are aware that with newer Java versions then
Class.forName is not required.

And I would rename getSQLDriver to getURLPrefix.

Arne