org.primefaces.model.LazyDataModel Maven / Gradle / Ivy
/*
* Copyright 2009-2014 PrimeTek.
*
* 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.primefaces.model;
import java.io.Serializable;
import java.util.List;
import java.util.Map;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.model.DataModel;
import javax.faces.model.DataModelEvent;
import javax.faces.model.DataModelListener;
/**
* Custom lazy loading DataModel to deal with huge datasets
*/
public abstract class LazyDataModel extends DataModel implements SelectableDataModel, Serializable {
private int rowIndex = -1;
private int rowCount;
private int pageSize;
private List data;
public LazyDataModel() {
super();
}
public boolean isRowAvailable() {
if(data == null) {
return false;
}
return rowIndex >= 0 && rowIndex < data.size();
}
public int getRowCount() {
return rowCount;
}
public T getRowData() {
return data.get(rowIndex);
}
public int getRowIndex() {
return this.rowIndex;
}
public void setRowIndex(int rowIndex) {
int oldIndex = this.rowIndex;
if(rowIndex == -1 || pageSize == 0)
this.rowIndex = -1;
else
this.rowIndex = (rowIndex % pageSize);
if(data == null) {
return;
}
DataModelListener[] listeners = getDataModelListeners();
if(listeners != null && oldIndex != this.rowIndex) {
Object rowData = null;
if(isRowAvailable()) {
rowData = getRowData();
}
DataModelEvent dataModelEvent = new DataModelEvent(this, rowIndex, rowData);
for (int i = 0; i < listeners.length; i++) {
listeners[i].rowSelected(dataModelEvent);
}
}
}
public Object getWrappedData() {
return data;
}
public void setWrappedData(Object list) {
this.data = (List) list;
}
public int getPageSize() {
return pageSize;
}
public void setPageSize(int pageSize) {
this.pageSize = pageSize;
}
public void setRowCount(int rowCount) {
this.rowCount = rowCount;
}
public List load(int first, int pageSize, String sortField, SortOrder sortOrder, Map filters) {
throw new UnsupportedOperationException("Lazy loading is not implemented.");
}
public List load(int first, int pageSize, List multiSortMeta, Map filters) {
throw new UnsupportedOperationException("Lazy loading is not implemented.");
}
public T getRowData(String rowKey) {
throw new UnsupportedOperationException(getMessage("getRowData(String rowKey) must be implemented by %s when basic rowKey algorithm is not used [component=%s,view=%s]."));
}
public Object getRowKey(T object) {
throw new UnsupportedOperationException(getMessage("getRowKey(T object) must be implemented by %s when basic rowKey algorithm is not used [component=%s,view=%s]."));
}
private String getMessage(String format) {
FacesContext facesContext = FacesContext.getCurrentInstance();
String viewId = facesContext.getViewRoot().getViewId();
UIComponent component = UIComponent.getCurrentComponent(facesContext);
String clientId = component == null ? "" : component.getClientId(facesContext);
return String.format(format, getClass().getName(), clientId, viewId);
}
}