Java tutorial
/***************************************************************************** * * Copyright (C) Zenoss, Inc. 2011, all rights reserved. * * This content is made available according to terms specified in * License.zenoss under the directory where your Zenoss product is installed. * ****************************************************************************/ package org.zenoss.zep.dao.impl; import org.springframework.jdbc.core.RowMapper; import org.springframework.jdbc.core.simple.SimpleJdbcOperations; import org.zenoss.protobufs.zep.Zep.DaemonHeartbeat; import org.zenoss.zep.ZepException; import org.zenoss.zep.annotations.TransactionalReadOnly; import org.zenoss.zep.annotations.TransactionalRollbackAllExceptions; import org.zenoss.zep.dao.HeartbeatDao; import org.zenoss.zep.dao.impl.compat.DatabaseCompatibility; import org.zenoss.zep.dao.impl.compat.NestedTransactionService; import org.zenoss.zep.dao.impl.compat.TypeConverter; import org.zenoss.zep.dao.impl.SimpleJdbcTemplateProxy; import java.lang.reflect.Proxy; import javax.sql.DataSource; import java.sql.ResultSet; import java.sql.SQLException; import java.util.Collections; import java.util.HashMap; import java.util.List; import java.util.Map; /** * Implementation of {@link org.zenoss.zep.dao.HeartbeatDao}. */ public class HeartbeatDaoImpl implements HeartbeatDao { private static final String COLUMN_MONITOR = "monitor"; private static final String COLUMN_DAEMON = "daemon"; private static final String COLUMN_TIMEOUT_SECONDS = "timeout_seconds"; private static final String COLUMN_LAST_TIME = "last_time"; private final SimpleJdbcOperations template; private DatabaseCompatibility databaseCompatibility; private NestedTransactionService nestedTransactionService; public HeartbeatDaoImpl(DataSource ds) { this.template = (SimpleJdbcOperations) Proxy.newProxyInstance(SimpleJdbcOperations.class.getClassLoader(), new Class<?>[] { SimpleJdbcOperations.class }, new SimpleJdbcTemplateProxy(ds)); } public void setDatabaseCompatibility(DatabaseCompatibility databaseCompatibility) { this.databaseCompatibility = databaseCompatibility; } public void setNestedTransactionService(NestedTransactionService nestedTransactionService) { this.nestedTransactionService = nestedTransactionService; } @Override @TransactionalRollbackAllExceptions public void createHeartbeat(DaemonHeartbeat heartbeat) throws ZepException { TypeConverter<Long> timestampConverter = databaseCompatibility.getTimestampConverter(); final long now = System.currentTimeMillis(); final Map<String, Object> fields = new HashMap<String, Object>(); fields.put(COLUMN_MONITOR, heartbeat.getMonitor()); fields.put(COLUMN_DAEMON, heartbeat.getDaemon()); fields.put(COLUMN_TIMEOUT_SECONDS, heartbeat.getTimeoutSeconds()); fields.put(COLUMN_LAST_TIME, timestampConverter.toDatabaseType(now)); String insertSql = "INSERT INTO daemon_heartbeat (monitor, daemon, timeout_seconds, last_time)" + " VALUES(:monitor, :daemon, :timeout_seconds, :last_time)"; String updateSql = "UPDATE daemon_heartbeat SET timeout_seconds=:timeout_seconds, last_time=:last_time" + " WHERE monitor=:monitor AND daemon=:daemon"; // In most cases, we insert and then retry as an update, however in these cases we will mostly be doing updates // so we try an update first before the insert/update. DaoUtils.updateOrInsert(nestedTransactionService, template, insertSql, updateSql, fields); } @Override @TransactionalReadOnly public List<DaemonHeartbeat> findAll() throws ZepException { final String sql = "SELECT * FROM daemon_heartbeat"; return this.template.query(sql, MAPPER); } @Override @TransactionalReadOnly public List<DaemonHeartbeat> findByMonitor(String monitor) throws ZepException { final Map<String, String> fields = Collections.singletonMap(COLUMN_MONITOR, monitor); final String sql = "SELECT * FROM daemon_heartbeat WHERE monitor=:monitor"; return this.template.query(sql, MAPPER, fields); } @Override @TransactionalRollbackAllExceptions public int deleteAll() throws ZepException { final String sql = "DELETE FROM daemon_heartbeat"; return this.template.update(sql); } @Override @TransactionalRollbackAllExceptions public int deleteByMonitor(String monitor) throws ZepException { final Map<String, String> fields = Collections.singletonMap(COLUMN_MONITOR, monitor); final String sql = "DELETE FROM daemon_heartbeat WHERE monitor=:monitor"; return this.template.update(sql, fields); } @Override @TransactionalRollbackAllExceptions public int deleteByMonitorAndDaemon(String monitor, String daemon) throws ZepException { final Map<String, String> fields = new HashMap<String, String>(2); fields.put(COLUMN_MONITOR, monitor); fields.put(COLUMN_DAEMON, daemon); final String sql = "DELETE FROM daemon_heartbeat WHERE monitor=:monitor AND daemon=:daemon"; return this.template.update(sql, fields); } private final RowMapper<DaemonHeartbeat> MAPPER = new RowMapper<DaemonHeartbeat>() { @Override public DaemonHeartbeat mapRow(ResultSet rs, int rowNum) throws SQLException { TypeConverter<Long> timestampConverter = databaseCompatibility.getTimestampConverter(); DaemonHeartbeat.Builder hb = DaemonHeartbeat.newBuilder(); hb.setMonitor(rs.getString(COLUMN_MONITOR)); hb.setDaemon(rs.getString(COLUMN_DAEMON)); hb.setTimeoutSeconds(rs.getInt(COLUMN_TIMEOUT_SECONDS)); hb.setLastTime(timestampConverter.fromDatabaseType(rs, COLUMN_LAST_TIME)); return hb.build(); } }; }