public void

public class ContentDao {

	private DataSource dataSource;

	public ContentDao() {
		try {
			Context context = new InitialContext();
			dataSource = (DataSource)context.lookup("java:comp/env/jdbc/Oracle11g");
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	public ArrayList<ContentDto> list() {
		ArrayList<ContentDto> ContentDtos = new ArrayList<ContentDto>();
		
		Connection conn = null;
		PreparedStatement pstmt = null;
		ResultSet rs = null;
		try {
			conn = dataSource.getConnection();
			String query = "SELECT * FROM TEST_BOARD";
			pstmt = conn.prepareStatement(query);
			rs = pstmt.executeQuery();
			while (rs.next()) {
				// ...
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			try {
				if (rs != null) rs.close();
				if (pstmt != null) pstmt.close();
				if (conn != null) conn.close();
			} catch (Exception e2) {
				e2.printStackTrace();
			}
		}
		return ContentDtos;
	}	
}

위와 같이 찾을 수 없다는 오류가 나오면 JSTL을 다운로드하여 설치하면 된다.

다운로드 : https://tomcat.apache.org/taglibs.html

C:\Java\jre1.8.0_162\lib\ext 등과 같은 외부 라이브러리 폴더에 넣어주면 된다.

Connection connection;
Statement statement;
ResultSet resultSet;

String driver = "oracle.jdbc.driver.OracleDriver";
String url = "jdbc:oracle:thin:@localhost:1521:xe";
String uid = "publicvoid";
String upw = "privatevoid";
String query = "select * from void_members";

try {
	Class.forName(driver);
	connection = DriverManager.getConnection(url, uid, upw);
	statement = connection.createStatement();
	resultSet = statement.executeQuery(query);
	
	while (resultSet.next()) {
		String id = resultSet.getString("user_id");
		String pw = resultSet.getString("user_pw");
		String name = resultSet.getString("user_name");
		String mobile = resultSet.getString("user_mobile");
		out.println("아이디 : " + id + " / 패스워드 : " + pw + " / 이름 : " + name + " / 휴대전화 : " + mobile);
	}
} catch (Exception exception) {
	exception.printStackTrace();
} finally {
	try {
		if (resultSet != null) resultSet.close();
		if (statement != null) statement.close();
		if (connection != null) connection.close();
	} catch (Exception exception2) {
		exception2.printStackTrace();
	}
}