Spring JDBC

Spring Jdbc Abstraction Layer. The Spring-JDBC component is a part of the Spring framework and is an abstraction on top of the standard Java JDBC API. It takes care of all the low-level API-calls and

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<source lang="java"> //lets imagine a case with an object named "Candy" public class CandyDataService{

private static final String INSERT_QUERY = "INSERT INTO CANDY(param1,param2) VALUES(?,?)"; private static final String DELETE_QUERY = "DELETE FROM CANDY WHERE ID=?"; private static final String SELECT_ALL_QUERY = "SELECT * FROM CANDY";

//Local database declarated, just for this examble HsqlDatabase db = new HsqlDatabase();

//Database connection JdbcTemplate jdbcTemplate = new JdbcTemplate( new SingleConnectionDataSource(db.conn, false));

//Insert private void insertCandy(Candy candy) { jdbcTemplate.update(INSERT_QUERY, param1, param2, param...); }

//Multi-Inserts public void insertCandies(List<Candy> candies) { for (Candy candy : candies) { insertCandy(candy); } }

//Delete Method public void deleteCandy(int id) { jdbcTemplate.update(DELETE_QUERY, id); }

//Get all candies with Auto-Mapping public List<Candy> retrieveAllCandies() throws SQLException{ jdbcTemplate.query(SELECT_ALL_QUERY, new BeanPropertyRowMapper<Candy>(Candy.class)); }

//Get all candies with Custom-Mapping public List<Candy> retrieveAllCandies() throws SQLException{ jdbcTemplate.query(SELECT_ALL_QUERY, new RowMapper<Candy>(){ public Candy mapRow(ResultSet rs, int rowNum) throws SQLException{ //OR: Solution 1 //Take the results set and set into the Candy object return new Candy(rs.getInt(1), rs.getString(2), rs.getBoolean(3),...);

//OR: Solution 2 //Using encapsulation Candy candy = new Candy(); candy.setParam1(rs.getInt(1)); candy.setParam1(rs.getString(2)); candy.setParam3(rs.getBoolean(3)); return candy; } } //OR: Solution 3 new CandyMapper()); } }

/** * Create a Mapper to help organizing the code in Custom-Mapping method * So it becomes reusable * Can also be declared as "Public class" and move it to a different Package */ class CandyMapper implements RowMapper<Candy>{ public Candy mapRow(ResultSet rs, int rowNum) throws SQLException{

Candy candy = new Candy(); candy.setParam1(rs.getInt(1)); candy.setParam1(rs.getString(2)); candy.setParam3(rs.getBoolean(3)); return candy; } } </source>