columnhandler.java

exTreme taglib的使用

/*
 * Copyright 2004 original author or authors.
 *
 * 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.extremecomponents.table.handler;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.apache.commons.lang.StringUtils;
import org.extremecomponents.table.bean.Column;
import org.extremecomponents.table.cell.Cell;
import org.extremecomponents.table.core.BaseModel;
import org.extremecomponents.table.core.TableModelUtils;

/**
 * The first pass over the table just loads up the column properties. The
 * properties will be loaded up and held here.
 * 
 * @author Jeff Johnston
 */
public class ColumnHandler {
    private BaseModel model;
    private List columns = new ArrayList(); // keeps columns in order
    private Map lookup = new HashMap(); // fast lookup capability
    private Column firstColumn;
    private Column lastColumn;

    public ColumnHandler(BaseModel model) {
        this.model = model;
    }

    public void addAutoGenerateColumn(Column column) {
        column.addAttribute(Column.IS_AUTO_GENERATE_COLUMN, "true");
        addColumn(column);
    }

    public void addColumn(Column column) {
        if (!isViewAllowed(column)) {
            return;
        }

        if (firstColumn == null) {
            firstColumn = column;
        }
        lastColumn = column;

        columns.add(column);
        lookup.put(column.getProperty(), column);
    }

    public Column getColumn(String property) {
        return (Column) lookup.get(property);
    }

    public int columnCount() {
        return columns.size();
    }

    public List getColumns() {
        return columns;
    }

    public boolean hasMetatData() {
        return columnCount() > 0;
    }

    public boolean isFirstColumn(String property) {
        return firstColumn.getProperty().equals(property);
    }

    public boolean isLastColumn(String property) {
        return lastColumn.getProperty().equals(property);
    }

    public List getFilterColumns() {
        boolean cleared = model.getLimit().isCleared();

        for (Iterator iter = columns.iterator(); iter.hasNext();) {
            Column column = (Column) iter.next();
            String value = model.getLimit().getFilterSet().getValue(column.getProperty());
            if (cleared || StringUtils.isEmpty(value)) {
                value = "";
            }
            Cell cell = TableModelUtils.buildFilterCell(model, column, value);
            column.setValue(cell.html());
            cell.destroy();
        }

        return columns;
    }

    public List getHeaderColumns() {
        for (Iterator iter = columns.iterator(); iter.hasNext();) {
            Column column = (Column) iter.next();
            Cell cell = TableModelUtils.buildHeaderCell(model, column, column.getTitle());

            boolean invokeExport = model.getExportHandler().invokeExport();
            if (!invokeExport) {
                column.setValue(cell.html());
            } else {
                column.setValue(column.getTitle());
            }

            cell.destroy();
        }

        return columns;
    }

    private boolean isViewAllowed(Column column) {
        String view = model.getTableHandler().getTable().getView();

        boolean invokeExport = model.getExportHandler().invokeExport();
        if (invokeExport) {
            view = model.getExportHandler().getCurrentExport().getView();
        }

        boolean allowView = allowView(column, view);
        boolean denyView = denyView(column, view);

        if (allowView & !denyView) {
            return true;
        }

        return false;
    }

    private boolean allowView(Column column, String view) {
        String viewsAllowed = column.getViewsAllowed();
        if (StringUtils.isBlank(viewsAllowed)) {
            return true;
        }

        String split[] = StringUtils.split(viewsAllowed, ",");
        for (int i = 0; i < split.length; i++) {
            if (view.equals(split[i])) {
                return true;
            }
        }

        return false;
    }

    private boolean denyView(Column column, String view) {
        String viewsDenied = column.getViewsDenied();
        if (StringUtils.isBlank(viewsDenied)) {
            return false;
        }

        String split[] = StringUtils.split(viewsDenied, ",");
        for (int i = 0; i < split.length; i++) {
            if (view.equals(split[i])) {
                return true;
            }
        }

        return false;
    }

    public void destroy() {
        columns.clear();
        columns = null;
        lookup.clear();
        lookup = null;
        firstColumn = null;
        lastColumn = null;
    }
}