Main.java Source code

Java tutorial

Introduction

Here is the source code for Main.java

Source

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLWarning;
import java.sql.Statement;

public class Main {
    public static void main(String[] args) throws Exception {

        Connection conn = getHSQLConnection();

        conn.setAutoCommit(false);
        Statement st = conn.createStatement();
        st.executeUpdate("create table survey (id int,name varchar(30));");
        st.executeUpdate("insert into survey (id,name ) values (1,'nameValue')");
        st = conn.createStatement();
        ResultSet rs = st.executeQuery("SELECT * FROM survey");

        outputResultSet(rs);

        checkForWarning(rs.getWarnings());

        rs.close();
        st.close();
        conn.close();

    }

    static boolean checkForWarning(SQLWarning w) {
        if (w == null) {
            return false;
        }
        do {
            System.err.println("Warning:\nMessage: " + w.getMessage());
            System.err.println("SQL state: " + w.getSQLState());
            System.err.println("Vendor code: " + w.getErrorCode() + "\n----------------");
        } while ((w = w.getNextWarning()) != null);
        return true;
    }

    private static void outputResultSet(ResultSet rs) throws Exception {
        ResultSetMetaData rsMetaData = rs.getMetaData();
        int numberOfColumns = rsMetaData.getColumnCount();
        for (int i = 1; i < numberOfColumns + 1; i++) {
            String columnName = rsMetaData.getColumnName(i);
            System.out.print(columnName + "   ");

        }
        System.out.println();
        System.out.println("----------------------");

        while (rs.next()) {
            for (int i = 1; i < numberOfColumns + 1; i++) {
                System.out.print(rs.getString(i) + "   ");
            }
            System.out.println();
        }

    }

    private static Connection getHSQLConnection() throws Exception {
        Class.forName("org.hsqldb.jdbcDriver");
        String url = "jdbc:hsqldb:mem:data/tutorial";

        return DriverManager.getConnection(url, "sa", "");
    }
}