package com.wrox.tourism.db;import com.wrox.tourism.entity.UserRole;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;public class UserRoleDAO {  private Connection con;  public UserRoleDAO(Connection con) {    this.con = con;  }  public void create(UserRole userRole) throws CreateException {    PreparedStatement ps = null;    String sql = "INSERT INTO user_role VALUES (?,?)";    try {      if (con.isClosed()) {        throw new IllegalStateException("error.unexpected");      }      ps = con.prepareStatement(sql);      ps.setString(1,userRole.getUserId());      ps.setString(2,userRole.getRoleName());      if (ps.executeUpdate() != 1) {        throw new CreateException("error.create.userRole");      }    } catch (SQLException e) {      try {        findByPrimaryKey(          userRole.getUserId(),            userRole.getRoleName());      } catch (FinderException fe) {        fe.printStackTrace();        throw new RuntimeException("error.unexpected");      }      throw new DuplicateKeyException(        "error.duplicate.userRole");    } finally {      try {        if (ps != null)          ps.close();      } catch (SQLException e) {        e.printStackTrace();        throw new RuntimeException("error.unexpected");      }    }  }  public void remove(String userId,String roleName) {    PreparedStatement ps = null;    String sql = "DELETE FROM user_role " +        "WHERE user_id = ? AND role_name = ?";    try {      if (con.isClosed()) {        throw new IllegalStateException("error.unexpected");      }      ps = con.prepareStatement(sql);      ps.setString(1,userId);      ps.setString(2,roleName);      if (ps.executeUpdate() < 1) {        throw new NoSuchEntityException(          "error.removed.userRole");      }    } catch (SQLException e) {      e.printStackTrace();      throw new RuntimeException("error.unexpected");    } finally {      try {        if (ps != null)          ps.close();      } catch (SQLException e) {        e.printStackTrace();        throw new RuntimeException("error.unexpected");      }    }  }  public UserRole findByPrimaryKey(String userId,String roleName)    throws FinderException {    PreparedStatement ps = null;    ResultSet rs = null;    UserRole userRole = null;    String sql = "SELECT * from user_role " +        "WHERE user_id = ? AND role_name = ?";    try {      if (con.isClosed()) {        throw new IllegalStateException("error.unexpected");      }      ps = con.prepareStatement(sql);      ps.setString(1,userId);      ps.setString(2,roleName);      rs = ps.executeQuery();      if (rs.next()) {        userRole = new UserRole();        userRole.setUserId(rs.getString(1));        userRole.setRoleName(rs.getString(2));        return userRole;      } else {        throw new ObjectNotFoundException(          "error.removed.userRole");      }    } catch (SQLException e) {      e.printStackTrace();      throw new RuntimeException("error.unexpected");    } finally {      try {        if (ps != null)          ps.close();        if (rs != null)          rs.close();      } catch (SQLException e) {        e.printStackTrace();        throw new RuntimeException("error.unexpected");      }    }  }}