Cleanup: Remove dead code from JndiSqlMap

An earlier version of the `JndiSqlMap` managed the JDBC connection on
object level instead of method level. When this behaviour was changed,
some old unused variables and methods remained in the file. These are
removed with this commit.

Author: cboehme

src/main/java/org/culturegraph/mf/morph/maps/JndiSqlMap.java

@@ -21,7 +21,7 @@
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
-import java.sql.Statement;
+
 import javax.naming.InitialContext;
 import javax.naming.NamingException;
 import javax.sql.DataSource;
@@ -33,26 +33,13 @@
 
 /**
  * @author Daniel
- * 
+ *
  */
 public final class JndiSqlMap extends AbstractReadOnlyMap<String, String> implements Closeable {
 
 	private static final Logger LOG = LoggerFactory.getLogger(JndiSqlMap.class);
 	private DataSource datasource;
 	private String query;
-	private Connection connection;
-	
-
-	@Override
-	public void close() throws IOException {
-		try {
-			if (connection != null) {
-				connection.close();
-			}
-		} catch (SQLException e) {
-			throw new MorphException(e);
-		}
-	}
 
 	protected DataSource getDatasource() {
 		return datasource;
@@ -61,7 +48,7 @@ protected DataSource getDatasource() {
 	public void setDatasource(final String name) {
 		try {
 			this.datasource = (DataSource) new InitialContext().lookup(name);
-		} catch (NamingException e) {
+		} catch (final NamingException e) {
 			throw new MorphException(e);
 		}
 	}
@@ -85,25 +72,30 @@ public String get(final Object key) {
 				resultString = resultSet.getString(1);
 			}
 			resultSet.close();
-		} catch (SQLException e) {
+		} catch (final SQLException e) {
 			throw new MorphException(e);
 		} finally {
 			if(stmt != null){
 				try {
 					stmt.close();
-				} catch (SQLException e) {
+				} catch (final SQLException e) {
 					LOG.error("Can't close SQL-Statement.", e);
 				}
 			}
 			if(con != null){
 				try {
 					con.close();
-				} catch (SQLException e) {
+				} catch (final SQLException e) {
 					LOG.error("Can't close Connection.", e);
 				}
 			}
 		}
 		return resultString;
 	}
 
+	@Override
+	public void close() throws IOException {
+		// Nothing to do
+	}
+
 }