Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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.googlecode.wicket.kendo.ui.datatable; import java.util.Iterator; import java.util.List; import org.apache.wicket.Application; import org.apache.wicket.Session; import org.apache.wicket.ajax.json.JSONException; import org.apache.wicket.ajax.json.JSONObject; import org.apache.wicket.behavior.AbstractAjaxBehavior; import org.apache.wicket.core.util.lang.PropertyResolver; import org.apache.wicket.core.util.lang.PropertyResolverConverter; import org.apache.wicket.extensions.markup.html.repeater.data.sort.ISortStateLocator; import org.apache.wicket.extensions.markup.html.repeater.data.sort.SortOrder; import org.apache.wicket.extensions.markup.html.repeater.data.table.filter.IFilterStateLocator; import org.apache.wicket.markup.repeater.data.IDataProvider; import org.apache.wicket.model.IModel; import org.apache.wicket.request.IRequestCycle; import org.apache.wicket.request.IRequestHandler; import org.apache.wicket.request.IRequestParameters; import org.apache.wicket.request.cycle.RequestCycle; import org.apache.wicket.request.http.WebResponse; import org.apache.wicket.util.convert.ConversionException; import com.googlecode.wicket.jquery.core.Options; import com.googlecode.wicket.jquery.core.utils.BuilderUtils; import com.googlecode.wicket.kendo.ui.datatable.column.IColumn; import com.googlecode.wicket.kendo.ui.datatable.column.PropertyColumn; import com.googlecode.wicket.kendo.ui.utils.PropertyUtils; /** * Provides the {@link DataTable} data source {@link AbstractAjaxBehavior} * * @param <T> the type of the model object * @author Sebastien Briquet - sebfz1 */ public class DataProviderBehavior<T> extends AbstractAjaxBehavior { private static final long serialVersionUID = 1L; private static final String ASC = "asc"; /** The max number of filtered column */ private static final int COLS = 20; private final IDataProvider<T> provider; private final IModel<List<IColumn>> columns; /** * Constructor * * @param columns the list of {@link IColumn} * @param provider the {@link IDataProvider} */ public DataProviderBehavior(final IModel<List<IColumn>> columns, final IDataProvider<T> provider) { this.columns = columns; this.provider = provider; } @SuppressWarnings("unchecked") protected void setSort(String property, SortOrder order) { ISortStateLocator<String> locator = (ISortStateLocator<String>) this.provider; locator.getSortState().setPropertySortOrder(property, order); } @Override public void onRequest() { final RequestCycle requestCycle = RequestCycle.get(); final IRequestParameters parameters = requestCycle.getRequest().getQueryParameters(); final int first = parameters.getParameterValue("skip").toInt(0); final int count = parameters.getParameterValue("take").toInt(0); // ISortStateLocator // if (this.provider instanceof ISortStateLocator<?>) { String property = parameters.getParameterValue("sort[0][field]").toOptionalString(); String direction = parameters.getParameterValue("sort[0][dir]").toOptionalString(); if (property != null) { this.setSort(PropertyUtils.unescape(property), direction == null ? SortOrder.NONE : direction.equals(ASC) ? SortOrder.ASCENDING : SortOrder.DESCENDING); } } // IFilterStateLocator // if (this.provider instanceof IFilterStateLocator<?>) { @SuppressWarnings("unused") String logicPattern = "filter[logic]"; String fieldPattern = "filter[filters][%d][field]"; String valuePattern = "filter[filters][%d][value]"; @SuppressWarnings("unused") String operatorPattern = "filter[filters][%d][operator]"; // TODO: implement logic & operator (new IFilterStateLocator interface?) @SuppressWarnings("unchecked") T object = ((IFilterStateLocator<T>) this.provider).getFilterState(); PropertyResolverConverter converter = this.newPropertyResolverConverter(); for (int i = 0; i < COLS; i++) { String field = parameters.getParameterValue(String.format(fieldPattern, i)).toOptionalString(); String value = parameters.getParameterValue(String.format(valuePattern, i)).toOptionalString(); if (field != null) { PropertyResolver.setValue(PropertyUtils.unescape(field), object, value, converter); } else { break; } } } requestCycle.scheduleRequestHandlerAfterCurrent(this.newRequestHandler(first, count)); } /** * Get a new {@link PropertyResolverConverter} * * @return a new {@code PropertyResolverConverter} */ protected PropertyResolverConverter newPropertyResolverConverter() { return new PropertyResolverConverter(Application.get().getConverterLocator(), Session.get().getLocale()); } /** * Gets the new {@link IRequestHandler} that will respond the data in a json format * * @param first the first row number * @param count the count of rows * @return a new {@code IRequestHandler} */ private IRequestHandler newRequestHandler(final int first, final int count) { return new IRequestHandler() { @Override public void respond(final IRequestCycle requestCycle) { WebResponse response = (WebResponse) requestCycle.getResponse(); final String encoding = Application.get().getRequestCycleSettings().getResponseRequestEncoding(); response.setContentType("application/json; charset=" + encoding); response.disableCaching(); final long size = provider.size(); final Iterator<? extends T> iterator = provider.iterator(first, count); // builds JSON result // StringBuilder builder = new StringBuilder(); builder.append("{ "); BuilderUtils.append(builder, "__count", size); builder.append(", "); builder.append(Options.QUOTE).append("results").append(Options.QUOTE).append(": "); builder.append("[ "); if (iterator != null) { for (int index = 0; iterator.hasNext(); index++) { if (index > 0) { builder.append(", "); } builder.append(DataProviderBehavior.this.newJsonRow(iterator.next())); } } builder.append(" ] }"); response.write(builder); } @Override public void detach(final IRequestCycle requestCycle) { provider.detach(); } }; } /** * Gets a new JSON object from the bean * * @param bean T object * @return a new JSON object */ protected String newJsonRow(T bean) { JSONObject object = new JSONObject(); try { for (IColumn column : this.columns.getObject()) { if (column instanceof PropertyColumn) { PropertyColumn pc = (PropertyColumn) column; object.put(pc.getField(), pc.getValue(bean)); } } } catch (JSONException e) { throw new ConversionException(e); } return object.toString(); } }