Java tutorial
/* Copyright 2013-2015 www.snakerflow.com. * * 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 org.snaker.engine.access.jdbc; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.SQLException; import java.util.Collections; import java.util.List; import java.util.Map; import javax.sql.DataSource; import org.apache.commons.dbutils.QueryRunner; import org.apache.commons.dbutils.handlers.ScalarHandler; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.snaker.engine.SnakerException; import org.snaker.engine.access.AbstractDBAccess; import org.snaker.engine.DBAccess; import org.snaker.engine.entity.Process; import org.snaker.engine.helper.ClassHelper; /** * JDBC?? * cglib+ThreadLocale * @see org.snaker.engine.access.transaction.DataSourceTransactionInterceptor * @author yuqs * @since 1.0 */ public class JdbcAccess extends AbstractDBAccess implements DBAccess { private static final Logger log = LoggerFactory.getLogger(JdbcAccess.class); /** * dbutilsQueryRunner */ private QueryRunner runner = new QueryRunner(true); /** * jdbc?? */ protected DataSource dataSource; /** * setter * @param dataSource */ public void setDataSource(DataSource dataSource) { this.dataSource = dataSource; } public void initialize(Object accessObject) { if (accessObject == null) return; if (accessObject instanceof DataSource) { this.dataSource = (DataSource) accessObject; } } /** * ? * @return * @throws java.sql.SQLException */ protected Connection getConnection() throws SQLException { return JdbcHelper.getConnection(dataSource); } /** * JDBC?BLOB */ public void saveProcess(Process process) { super.saveProcess(process); if (process.getBytes() != null) { Connection conn = null; PreparedStatement pstmt = null; try { conn = getConnection(); pstmt = conn.prepareStatement(PROCESS_UPDATE_BLOB); pstmt.setBytes(1, process.getBytes()); pstmt.setString(2, process.getId()); pstmt.execute(); } catch (Exception e) { throw new SnakerException(e.getMessage(), e.getCause()); } finally { try { JdbcHelper.close(pstmt); } catch (SQLException e) { throw new SnakerException(e.getMessage(), e.getCause()); } } } } /** * JDBC?BLOB */ public void updateProcess(Process process) { super.updateProcess(process); if (process.getBytes() != null) { Connection conn = null; PreparedStatement pstmt = null; try { conn = getConnection(); pstmt = conn.prepareStatement(PROCESS_UPDATE_BLOB); pstmt.setBytes(1, process.getBytes()); pstmt.setString(2, process.getId()); pstmt.execute(); } catch (Exception e) { throw new SnakerException(e.getMessage(), e.getCause()); } finally { try { JdbcHelper.close(pstmt); } catch (SQLException e) { throw new SnakerException(e.getMessage(), e.getCause()); } } } } /** * * @param column ? * @param sql sql? * @param params ? * @return */ public Object query(int column, String sql, Object... params) { Object result; try { if (log.isDebugEnabled()) { log.debug("??=\n" + sql); } result = runner.query(getConnection(), sql, new ScalarHandler(column), params); } catch (SQLException e) { log.error(e.getMessage(), e); throw new RuntimeException(e.getMessage(), e); } return result; } public Integer getLatestProcessVersion(String name) { String where = " where name = ?"; Object result = query(1, QUERY_VERSION + where, name); return new Long(ClassHelper.castLong(result)).intValue(); } public boolean isORM() { return false; } public void saveOrUpdate(Map<String, Object> map) { String sql = (String) map.get(KEY_SQL); Object[] args = (Object[]) map.get(KEY_ARGS); try { if (log.isDebugEnabled()) { log.debug("?(??)=\n" + sql); } runner.update(getConnection(), sql, args); } catch (SQLException e) { log.error(e.getMessage(), e); throw new RuntimeException(e.getMessage(), e); } } public <T> T queryObject(Class<T> clazz, String sql, Object... args) { List<T> result = null; try { if (log.isDebugEnabled()) { log.debug("??=\n" + sql); } result = runner.query(getConnection(), sql, new BeanPropertyHandler<T>(clazz), args); return JdbcHelper.requiredSingleResult(result); } catch (SQLException e) { log.error(e.getMessage(), e); throw new SnakerException(e.getMessage(), e.getCause()); } } public <T> List<T> queryList(Class<T> clazz, String sql, Object... args) { try { if (log.isDebugEnabled()) { log.debug("?=\n" + sql); } return runner.query(getConnection(), sql, new BeanPropertyHandler<T>(clazz), args); } catch (SQLException e) { log.error(e.getMessage(), e); throw new SnakerException(e.getMessage(), e.getCause()); } } public Object queryCount(String sql, Object... args) { return query(1, sql, args); } }