Main.java Source code

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Here is the source code for Main.java

Source

import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class Main {
    public static void main(String[] args) throws Exception {
        Connection conn = getMySqlConnection();
        System.out.println("Got Connection.");
        Statement st = conn.createStatement();
        st.executeUpdate("drop table survey;");
        st.executeUpdate("create table survey (id int,name varchar(30));");
        st.executeUpdate("insert into survey (id,name ) values (1,'nameValue')");

        ResultSet rsColumns = null;
        DatabaseMetaData meta = conn.getMetaData();
        rsColumns = meta.getColumns(null, null, "survey", null);
        while (rsColumns.next()) {
            String columnName = rsColumns.getString("COLUMN_NAME");
            System.out.println("column name=" + columnName);
            String columnType = rsColumns.getString("TYPE_NAME");
            System.out.println("type:" + columnType);
            int size = rsColumns.getInt("COLUMN_SIZE");
            System.out.println("size:" + size);
            int nullable = rsColumns.getInt("NULLABLE");
            if (nullable == DatabaseMetaData.columnNullable) {
                System.out.println("nullable true");
            } else {
                System.out.println("nullable false");
            }
            int position = rsColumns.getInt("ORDINAL_POSITION");
            System.out.println("position:" + position);

        }

        st.close();
        conn.close();
    }

    private static Connection getHSQLConnection() throws Exception {
        Class.forName("org.hsqldb.jdbcDriver");
        System.out.println("Driver Loaded.");
        String url = "jdbc:hsqldb:data/tutorial";
        return DriverManager.getConnection(url, "sa", "");
    }

    public static Connection getMySqlConnection() throws Exception {
        String driver = "org.gjt.mm.mysql.Driver";
        String url = "jdbc:mysql://localhost/demo2s";
        String username = "oost";
        String password = "oost";

        Class.forName(driver);
        Connection conn = DriverManager.getConnection(url, username, password);
        return conn;
    }

    public static Connection getOracleConnection() throws Exception {
        String driver = "oracle.jdbc.driver.OracleDriver";
        String url = "jdbc:oracle:thin:@localhost:1521:caspian";
        String username = "mp";
        String password = "mp2";

        Class.forName(driver); // load Oracle driver
        Connection conn = DriverManager.getConnection(url, username, password);
        return conn;
    }
}