Java tutorial
/* * #%L * server * %% * Copyright (C) 2012 - 2015 valdasraps * %% * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation, either version 3 of the * License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Lesser Public License for more details. * * You should have received a copy of the GNU General Lesser Public * License along with this program. If not, see * <http://www.gnu.org/licenses/lgpl-3.0.html>. * #L% */ package lt.emasina.resthub.server.factory; import java.math.BigDecimal; import java.sql.SQLException; import java.util.concurrent.Callable; import java.util.concurrent.ExecutionException; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; import java.util.concurrent.TimeUnit; import java.util.concurrent.TimeoutException; import javax.inject.Singleton; import lombok.extern.log4j.Log4j; import lt.emasina.resthub.model.MdColumn; import lt.emasina.resthub.server.cache.CcLob; import lt.emasina.resthub.server.cache.CcCount; import lt.emasina.resthub.server.cache.CcData; import lt.emasina.resthub.server.exception.ClientErrorException; import lt.emasina.resthub.server.exception.ServerErrorException; import lt.emasina.resthub.server.handler.LobHandler; import lt.emasina.resthub.server.handler.CountHandler; import lt.emasina.resthub.server.handler.DataHandler; import lt.emasina.resthub.server.handler.PagedHandler; import lt.emasina.resthub.server.query.Query; import org.hibernate.SQLQuery; import org.hibernate.Session; import org.hibernate.type.BigDecimalType; import org.hibernate.type.BlobType; import org.hibernate.type.CalendarType; import org.hibernate.type.ClobType; import org.hibernate.type.StringType; import org.hibernate.type.TextType; import org.hibernate.type.WrapperBinaryType; import org.restlet.data.Status; /** * DataFactory * @author valdo */ @Singleton @Log4j public class DataFactory { private static final String START_ROW_PARAM = "START_ROW___"; private static final String NUM_ROWS_PARAM = "NUMBER_OF_ROWS___"; public CcData getData(final Session session, final DataHandler handler) throws Exception { final Query q = handler.getQuery(); final SQLQuery query = getPagedSQLQuery(session, handler); for (MdColumn c : q.getColumns()) { switch (c.getType()) { case BLOB: query.addScalar(c.getName(), new BlobType()); break; case CLOB: query.addScalar(c.getName(), new ClobType()); break; case DATE: query.addScalar(c.getName(), new CalendarType()); break; case NUMBER: query.addScalar(c.getName(), new BigDecimalType()); break; case STRING: query.addScalar(c.getName(), new StringType()); break; } } if (log.isDebugEnabled()) { log.debug(query.getQueryString()); } ExecutorService executor = Executors.newSingleThreadExecutor(); Future<CcData> loopRows = executor.submit(new Callable<CcData>() { @Override @SuppressWarnings("unchecked") public CcData call() throws Exception { CcData cc = new CcData(); for (Object o : query.list()) { cc.addRow(q, o); } return cc; }; }); try { return loopRows.get(q.getTimeOut(), TimeUnit.SECONDS); } catch (ExecutionException | InterruptedException ex) { throw ex; } catch (TimeoutException ex) { throw new ServerErrorException(Status.SERVER_ERROR_GATEWAY_TIMEOUT, ex); } } public CcLob getLob(final Session session, final LobHandler handler) throws Exception { final Query q = handler.getQuery(); final SQLQuery query = getPagedSQLQuery(session, handler); final MdColumn c = handler.getMdColumn(); switch (c.getType()) { case BLOB: query.addScalar(c.getName(), new WrapperBinaryType()); break; case CLOB: query.addScalar(c.getName(), new TextType()); break; default: throw new ClientErrorException(Status.CLIENT_ERROR_BAD_REQUEST, "Column %d (%s) expected to be LOB found %s", handler.getColumn(), c.getName(), c.getType().name()); } if (log.isDebugEnabled()) { log.debug(query.getQueryString()); } ExecutorService executor = Executors.newSingleThreadExecutor(); Future<CcLob> fetchData = executor.submit(new Callable<CcLob>() { @Override @SuppressWarnings("unchecked") public CcLob call() throws Exception { CcLob cc = new CcLob(); Object o = query.uniqueResult(); if (o != null) { switch (c.getType()) { case CLOB: cc.setValue((String) o); break; case BLOB: cc.setValue((Byte[]) o); break; } } return cc; }; }); try { return fetchData.get(q.getTimeOut(), TimeUnit.SECONDS); } catch (ExecutionException | InterruptedException ex) { throw ex; } catch (TimeoutException ex) { throw new ServerErrorException(Status.SERVER_ERROR_GATEWAY_TIMEOUT, ex); } } private SQLQuery getPagedSQLQuery(final Session session, final PagedHandler<?, ?> handler) throws SQLException { final Query q = handler.getQuery(); Integer perPage = handler.getPerPage(); Integer page = handler.getPage(); if (page == null || perPage == null) { perPage = q.getRowsLimit(); page = 1; } Integer startRow = perPage * (page - 1) + 1; if (handler instanceof LobHandler) { startRow = startRow + ((LobHandler) handler).getRow(); perPage = 1; } StringBuilder sb = new StringBuilder(); sb.append("select * from " + " (select ROWNUM ROW_NUMBER___, A.* from ("); sb.append(q.getSql()).append(") A").append(" where ROWNUM < (:").append(START_ROW_PARAM).append(" + :") .append(NUM_ROWS_PARAM).append(") ").append(") where ROW_NUMBER___ >= :").append(START_ROW_PARAM); String sql = sb.toString(); final SQLQuery query = session.createSQLQuery(sql); handler.applyParameters(query); query.setInteger(START_ROW_PARAM, startRow); query.setInteger(NUM_ROWS_PARAM, perPage); return query; } public CcCount getCount(Session session, CountHandler handler) throws SQLException { final Query q = handler.getQuery(); StringBuilder sb = new StringBuilder(); sb.append("select count(*) from (").append(handler.getQuery().getSql()).append(") "); String sql = sb.toString(); final SQLQuery query = session.createSQLQuery(sql); handler.applyParameters(query); if (log.isDebugEnabled()) { log.debug(query.getQueryString()); } ExecutorService executor = Executors.newSingleThreadExecutor(); Future<CcCount> func = executor.submit(new Callable<CcCount>() { @Override public CcCount call() throws Exception { CcCount cc = new CcCount(); cc.setValue(((BigDecimal) query.uniqueResult()).longValue()); return cc; } }); try { return func.get(q.getTimeOut(), TimeUnit.SECONDS); } catch (ExecutionException | InterruptedException ex) { throw new ServerErrorException(Status.SERVER_ERROR_INTERNAL, ex); } catch (TimeoutException ex) { throw new ServerErrorException(Status.SERVER_ERROR_GATEWAY_TIMEOUT, ex); } } }