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/* * JBoss, Home of Professional Open Source * Copyright 2012, Red Hat Middleware LLC, and individual contributors * by the @authors tag. See the copyright.txt in the distribution for a * full listing of individual contributors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * http://www.apache.org/licenses/LICENSE-2.0 * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.acme.spring.jdbc.repository.impl; import com.acme.spring.jdbc.domain.Stock; import com.acme.spring.jdbc.repository.StockRepository; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.jdbc.core.JdbcTemplate; import org.springframework.jdbc.core.PreparedStatementCreator; import org.springframework.jdbc.core.RowMapper; import org.springframework.jdbc.support.GeneratedKeyHolder; import org.springframework.jdbc.support.KeyHolder; import org.springframework.stereotype.Repository; import javax.sql.DataSource; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.text.MessageFormat; import java.util.List; /** * <p>A default implementation of {@link com.acme.spring.jdbc.repository.StockRepository} that uses JDBC for persistence * operations.</p> * * @author <a href="mailto:jmnarloch@gmail.com">Jakub Narloch</a> */ @Repository public class JdbcStockRepository implements StockRepository { /** * <p>Represents the instance of {@link JdbcTemplate} used for persistence operation.</p> */ private JdbcTemplate jdbcTemplate; /** * <p>Sets the data source.</p> * * @param dataSource the data source */ @Autowired public void setDataSource(DataSource dataSource) { jdbcTemplate = new JdbcTemplate(dataSource); } /** * <p>Creates new instance of {@link JdbcStockRepository}</p> */ public JdbcStockRepository() { // empty constructor } /** * {@inheritDoc} */ @Override public long save(final Stock stock) { // validates the input validateNoNull(stock, "stock"); validateNotEmpty(stock.getSymbol(), "symbol"); KeyHolder keyHolder = new GeneratedKeyHolder(); // performs the insert in the database jdbcTemplate.update(new PreparedStatementCreator() { public PreparedStatement createPreparedStatement(Connection connection) throws SQLException { PreparedStatement ps = connection.prepareStatement( "insert into Stock(name, symbol, value, date) values (?, ?, ?, ?)", new String[] { "id" }); int index = 1; ps.setString(index++, stock.getName()); ps.setString(index++, stock.getSymbol()); ps.setBigDecimal(index++, stock.getValue()); ps.setDate(index++, new java.sql.Date(stock.getDate().getTime())); return ps; } }, keyHolder); // retrieves the value primary key for the inserted key stock.setId((Long) keyHolder.getKey()); return stock.getId(); } /** * {@inheritDoc} */ @Override public void update(Stock stock) { // validates the input validateNoNull(stock, "stock"); validateNotEmpty(stock.getSymbol(), "symbol"); // performs the update in database jdbcTemplate.update("update Stock set name = ?, symbol = ?, value = ?, date = ? where id = ?", stock.getName(), stock.getSymbol(), stock.getValue(), stock.getDate(), stock.getId()); } /** * {@inheritDoc} */ @Override public Stock get(long id) { // retrieves the entity by it's id return jdbcTemplate.queryForObject("select id, name, symbol, value, date from Stock where id = ?", new Object[] { id }, new StockMapper()); } /** * {@inheritDoc} */ @Override public Stock getBySymbol(String symbol) { validateNotEmpty(symbol, "symbol"); // retrieves the entity by it's symbol return jdbcTemplate.queryForObject("select id, name, symbol, value, date from Stock where symbol = ?", new Object[] { symbol }, new StockMapper()); } /** * {@inheritDoc} */ @Override public List<Stock> getAll() { return jdbcTemplate.query("select id, name, symbol, value, date from Stock", new StockMapper()); } /** * <p>Validates that the passed parameter is not null or empty string, in case it isn't than {@link * IllegalArgumentException} is being thrown.</p> * * @param param the parameter to validate * @param parameterName the parameter name */ private void validateNotEmpty(String param, String parameterName) { validateNoNull(param, parameterName); if (param.trim().length() == 0) { throw new IllegalArgumentException( MessageFormat.format("The {0} can not be null or empty string.", parameterName)); } } /** * <p>Validates that the passed parameter is not null, in case it's null than the {@link IllegalArgumentException} * is being thrown.</p> * * @param param the parameter to validate * @param parameterName the parameter name */ private void validateNoNull(Object param, String parameterName) { if (param == null) { throw new IllegalArgumentException(MessageFormat.format("The '{0}' can not be null.", parameterName)); } } /** * <p>Stock mapper, used for mapping the rows returned from result set into {@link Stock} objects.</p> * * @author <a href="mailto:jmnarloch@gmail.com">Jakub Narloch</a> */ private static class StockMapper implements RowMapper<Stock> { /** * {@inheritDoc} */ public Stock mapRow(ResultSet rs, int rowNum) throws SQLException { int index = 1; Stock result = new Stock(); result.setId(rs.getLong(index++)); result.setName(rs.getString(index++)); result.setSymbol(rs.getString(index++)); result.setValue(rs.getBigDecimal(index++)); result.setDate(rs.getDate(index++)); return result; } } }