/** * * Copyright 2005 The Apache Software Foundation or its licensors, as applicable. * * 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.apache.tuscany.das.rdb.impl; import org.apache.tuscany.das.rdb.Command; import org.apache.tuscany.das.rdb.Pager; import commonj.sdo.DataObject; public class PagerImpl implements Pager { private final ReadCommandImpl command; private final int size; private int idx = 1; public PagerImpl(Command command, int size) { this.command = (ReadCommandImpl)command; this.command.enablePaging(); this.size = size; } public DataObject next() { int start = idx; int end = idx + size; idx += size; command.setStartRow(start); command.setEndRow(end); return command.executeQuery(); } public DataObject getPage(int page) { int end = (page * size) + 1; int start = end - size; idx = end; command.setStartRow(start); command.setEndRow(end); return command.executeQuery(); } public DataObject previous() { int start = idx - (2 * size); if ( start < 1 ) start = 1; int end = start + size; idx = end; command.setStartRow(start); command.setEndRow(end); return command.executeQuery(); } }