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POJDBC - Retrieve entire data as a List
 

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    <p>I'm trying to build a class that retrieves each row from a MySQL table and store it to a List but my code doesn't compile and throws me an error </p> <blockquote> <p>Error: Main method not found in class MySQLAccountsDatabankReader, please define the main method as: public static void main(String[] args)</p> </blockquote> <pre><code> import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.ArrayList; import java.util.List; import java.util.logging.Level; import java.util.logging.Logger; public class MySQLAccountsDatabankReader { private static List&lt;String[]&gt; accounts; public MySQLAccountsDatabankReader(String[] args) { Connection con = null; Statement st = null; ResultSet rs = null; String url = "jdbc:mysql://localhost:3306/test"; String user = "root"; String password = "mysql"; try { con = DriverManager.getConnection(url, user, password); st = con.createStatement(); rs = st.executeQuery("SELECT * FROM test.accounts;"); if (rs.next()) { ArrayList&lt;String[]&gt; accounts = new ArrayList&lt;String[]&gt;(); rs = st.executeQuery("SELECT * FROM test.accounts;"); int columnCount = rs.getMetaData().getColumnCount(); while (rs.next()) { String[] row = new String[columnCount]; for (int i = 0; i &lt; columnCount; i++) { row[i] = rs.getString(i + 1); } accounts.add(row); } } } catch (SQLException ex) { Logger lgr = Logger.getLogger(MySQLAccountsDatabankReader.class .getName()); lgr.log(Level.SEVERE, ex.getMessage(), ex); } finally { try { if (rs != null) { rs.close(); } if (st != null) { st.close(); } if (con != null) { con.close(); } } catch (SQLException ex) { Logger lgr = Logger.getLogger(MySQLAccountsDatabankReader.class .getName()); lgr.log(Level.WARNING, ex.getMessage(), ex); } } return accounts; } } </code></pre> <p>Revision 0.2 - I've got the following compilation error - Exception in thread "main" java.lang.Error: Unresolved compilation problems: accounts cannot be resolved accounts cannot be resolved to a variable</p> <pre><code>import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.ArrayList; import java.util.List; import java.util.logging.Level; import java.util.logging.Logger; public class MySQLAccountsDatabankReader { public static void main(String[] args) { MySQLAccountsDatabankReader reader = new MySQLAccountsDatabankReader(); List&lt;String[]&gt; accounts = reader.getAccounts(); } public List&lt;String[]&gt; getAccounts() { Connection con = null; Statement st = null; ResultSet rs = null; String url = "jdbc:mysql://localhost:3306/test"; String user = "root"; String password = "mysql"; try { con = DriverManager.getConnection(url, user, password); st = con.createStatement(); rs = st.executeQuery("SELECT * FROM test.accounts;"); if (rs.next()) { rs = st.executeQuery("SELECT * FROM test.accounts;"); int columnCount = rs.getMetaData().getColumnCount(); while (rs.next()) { String[] row = new String[columnCount]; for (int i = 0; i &lt; columnCount; i++) { row[i] = rs.getString(i + 1); } accounts.add(row); } return accounts; } } catch (SQLException ex) { Logger lgr = Logger.getLogger(MySQLAccountsDatabankReader.class .getName()); lgr.log(Level.SEVERE, ex.getMessage(), ex); } finally { try { if (rs != null) { rs.close(); } if (st != null) { st.close(); } if (con != null) { con.close(); } } catch (SQLException ex) { Logger lgr = Logger.getLogger(MySQLAccountsDatabankReader.class .getName()); lgr.log(Level.WARNING, ex.getMessage(), ex); } } } } </code></pre>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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