JDBC Example

jdbc-sample.java

package com.smc.jdbc;

import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.SQLException;
import java.sql.Statement;

public class JDBCStatementCreateExample {

	private static final String DB_DRIVER = "oracle.jdbc.driver.OracleDriver";
	private static final String DB_CONNECTION = "jdbc:oracle:thin:@localhost:1521:BEN";
	private static final String DB_USER = "user";
	private static final String DB_PASSWORD = "password";

	public static void main(String[] argv) {

		try {

			createDbUserTable();
			selectRecordsFromDbUserTable();
			insertRecordIntoDbUserTable();

		} catch (SQLException e) {

			System.out.println(e.getMessage());

		}

	}

	private static void createDbUserTable() throws SQLException {

		Connection dbConnection = null;
		Statement statement = null;

		String createTableSQL = "CREATE TABLE DBUSER("
				+ "USER_ID NUMBER(5) NOT NULL, "
				+ "USERNAME VARCHAR(20) NOT NULL, "
				+ "CREATED_BY VARCHAR(20) NOT NULL, "
				+ "CREATED_DATE DATE NOT NULL, " + "PRIMARY KEY (USER_ID) "
				+ ")";

		try {
			dbConnection = getDBConnection();
			statement = dbConnection.createStatement();

			System.out.println(createTableSQL);
                        // execute the SQL stetement
			statement.execute(createTableSQL);

			System.out.println("Table \"dbuser\" is created!");

		} catch (SQLException e) {

			System.out.println(e.getMessage());

		} finally {

			if (statement != null) {
				statement.close();
			}

			if (dbConnection != null) {
				dbConnection.close();
			}

		}

	}

	private static void selectRecordsFromDbUserTable() throws SQLException {

		Connection dbConnection = null;
		Statement statement = null;

		String selectTableSQL = "SELECT USER_ID, USERNAME from DBUSER";

		try {
			dbConnection = getDBConnection();
			statement = dbConnection.createStatement();

			System.out.println(selectTableSQL);

			// execute select SQL stetement
			ResultSet rs = statement.executeQuery(selectTableSQL);

			while (rs.next()) {

				String userid = rs.getString("USER_ID");
				String username = rs.getString("USERNAME");

				System.out.println("userid : " + userid);
				System.out.println("username : " + username);

			}

		} catch (SQLException e) {

			System.out.println(e.getMessage());

		} finally {

			if (statement != null) {
				statement.close();
			}

			if (dbConnection != null) {
				dbConnection.close();
			}

		}

	}

	private static void insertRecordIntoDbUserTable() throws SQLException {

		Connection dbConnection = null;
		Statement statement = null;

		String insertTableSQL = "INSERT INTO DBUSER"
				+ "(USER_ID, USERNAME, CREATED_BY, CREATED_DATE) " + "VALUES"
				+ "(1,'mkyong','system', " + "to_date('"
				+ getCurrentTimeStamp() + "', 'yyyy/mm/dd hh24:mi:ss'))";

		try {
			dbConnection = getDBConnection();
			statement = dbConnection.createStatement();

			System.out.println(insertTableSQL);

			// execute insert SQL stetement
			statement.executeUpdate(insertTableSQL);

			System.out.println("Record is inserted into DBUSER table!");

		} catch (SQLException e) {

			System.out.println(e.getMessage());

		} finally {

			if (statement != null) {
				statement.close();
			}

			if (dbConnection != null) {
				dbConnection.close();
			}

		}

	}
	
	private static Connection getDBConnection() {

		Connection dbConnection = null;

		try {

			Class.forName(DB_DRIVER);

		} catch (ClassNotFoundException e) {

			System.out.println(e.getMessage());

		}

		try {

			dbConnection = DriverManager.getConnection(
					DB_CONNECTION, DB_USER,DB_PASSWORD);
			return dbConnection;

		} catch (SQLException e) {

			System.out.println(e.getMessage());

		}

		return dbConnection;

	}

}