tabletag.java

一个比较不错的java分页标签,有源代码,开发者 可以学习学习

/**
 * Licensed under the Artistic License; you may not use this file
 * except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://displaytag.sourceforge.net/license.html
 *
 * THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */
package org.displaytag.tags;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.StringWriter;
import java.io.Writer;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspTagException;
import javax.servlet.jsp.JspWriter;

import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.collections.IteratorUtils;
import org.apache.commons.lang.ObjectUtils;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.lang.math.LongRange;
import org.apache.commons.lang.math.NumberUtils;
import org.apache.commons.lang.math.Range;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.displaytag.Messages;
import org.displaytag.decorator.TableDecorator;
import org.displaytag.exception.ExportException;
import org.displaytag.exception.FactoryInstantiationException;
import org.displaytag.exception.InvalidTagAttributeValueException;
import org.displaytag.exception.WrappedRuntimeException;
import org.displaytag.export.BinaryExportView;
import org.displaytag.export.ExportView;
import org.displaytag.export.ExportViewFactory;
import org.displaytag.export.TextExportView;
import org.displaytag.model.Cell;
import org.displaytag.model.Column;
import org.displaytag.model.HeaderCell;
import org.displaytag.model.Row;
import org.displaytag.model.TableModel;
import org.displaytag.pagination.PaginatedList;
import org.displaytag.pagination.PaginatedListSmartListHelper;
import org.displaytag.pagination.SmartListHelper;
import org.displaytag.properties.MediaTypeEnum;
import org.displaytag.properties.SortOrderEnum;
import org.displaytag.properties.TableProperties;
import org.displaytag.render.HtmlTableWriter;
import org.displaytag.util.CollectionUtil;
import org.displaytag.util.DependencyChecker;
import org.displaytag.util.Href;
import org.displaytag.util.ParamEncoder;
import org.displaytag.util.RequestHelper;
import org.displaytag.util.RequestHelperFactory;
import org.displaytag.util.TagConstants;


/**
 * This tag takes a list of objects and creates a table to display those objects. With the help of column tags, you
 * simply provide the name of properties (get Methods) that are called against the objects in your list that gets
 * displayed. This tag works very much like the struts iterator tag, most of the attributes have the same name and
 * functionality as the struts tag.
 * @author mraible
 * @author Fabrizio Giustina
 * @version $Revision: 1025 $ ($Author: fgiust $)
 */
public class TableTag extends HtmlTableTag
{

    /**
     * name of the attribute added to page scope when exporting, containing an MediaTypeEnum this can be used in column
     * content to detect the output type and to return different data when exporting.
     */
    public static final String PAGE_ATTRIBUTE_MEDIA = "mediaType"; //$NON-NLS-1$

    /**
     * If this variable is found in the request, assume the export filter is enabled.
     */
    public static final String FILTER_CONTENT_OVERRIDE_BODY = //
    "org.displaytag.filter.ResponseOverrideFilter.CONTENT_OVERRIDE_BODY"; //$NON-NLS-1$

    /**
     * D1597A17A6.
     */
    private static final long serialVersionUID = 899149338534L;

    /**
     * logger.
     */
    private static Log log = LogFactory.getLog(TableTag.class);

    /**
     * RequestHelperFactory instance used for link generation.
     */
    private static RequestHelperFactory rhf;

    /**
     * Object (collection, list) on which the table is based. This is not set directly using a tag attribute and can be
     * cleaned.
     */
    protected Object list;

    // -- start tag attributes --

    /**
     * Object (collection, list) on which the table is based. Set directly using the "list" attribute or evaluated from
     * expression.
     */
    protected Object listAttribute;

    /**
     * actual row number, updated during iteration.
     */
    private int rowNumber = 1;

    /**
     * name of the object to use for iteration. Can contain expressions.
     */
    private String name;

    /**
     * length of list to display.
     */
    private int length;

    /**
     * table decorator class name.
     */
    private String decoratorName;

    /**
     * page size.
     */
    private int pagesize;

    /**
     * list contains only viewable data.
     */
    private boolean partialList;

    /**
     * add export links.
     */
    private boolean export;

    /**
     * list offset.
     */
    private int offset;

    /**
     * Integer containing total size of the data displaytag is paginating
     */
    private Object size;

    /**
     * Name of the Integer in some scope containing the size of the data displaytag is paginating
     */
    private String sizeObjectName;

    /**
     * sort the full list?
     */
    private Boolean sortFullTable;

    /**
     * are we doing any local sorting? (defaults to True)
     */
    private boolean localSort = true;

    /**
     * Request uri.
     */
    private String requestUri;

    /**
     * Prepend application context to generated links.
     */
    private boolean dontAppendContext;

    /**
     * the index of the column sorted by default.
     */
    private int defaultSortedColumn = -1;

    /**
     * the sorting order for the sorted column.
     */
    private SortOrderEnum defaultSortOrder;

    /**
     * Name of parameter which should not be forwarded during sorting or pagination.
     */
    private String excludedParams;

    /**
     * Unique table id.
     */
    private String uid;

    /**
     * The variable name to store totals in.
     */
    private String varTotals;

    // -- end tag attributes --

    /**
     * table model - initialized in doStartTag().
     */
    private TableModel tableModel;

    /**
     * current row.
     */
    private Row currentRow;

    /**
     * next row.
     */

    /**
     * Used by various functions when the person wants to do paging - cleaned in doEndTag().
     */
    private SmartListHelper listHelper;

    /**
     * base href used for links - set in initParameters().
     */
    private Href baseHref;

    /**
     * table properties - set in doStartTag().
     */
    private TableProperties properties;

    /**
     * page number - set in initParameters().
     */
    private int pageNumber = 1;

    /**
     * Iterator on collection.
     */
    private Iterator tableIterator;

    /**
     * export type - set in initParameters().
     */
    private MediaTypeEnum currentMediaType;

    /**
     * daAfterBody() has been executed at least once?
     */
    private boolean doAfterBodyExecuted;

    /**
     * The param encoder used to generate unique parameter names. Initialized at the first use of encodeParameter().
     */
    private ParamEncoder paramEncoder;

    /**
     * Static footer added using the footer tag.
     */
    private String footer;

    /**
     * Is this the last iteration we will be performing? We only output the footer on the last iteration.
     */
    private boolean lastIteration;

    /**
     * Static caption added using the footer tag.
     */
    private String caption;

    /**
     * Child caption tag.
     */
    private CaptionTag captionTag;

    /**
     * Included row range. If no rows can be skipped the range is from 0 to Long.MAX_VALUE. Range check should be always
     * done using containsLong(). This is an instance of org.apache.commons.lang.math.Range, but it's declared as Object
     * to avoid runtime errors while Jasper tries to compile the page and commons lang 2.0 is not available. Commons
     * lang version will be checked in the doStartTag() method in order to provide a more user friendly message.
     */
    private Object filteredRows;

    /**
     * The paginated list containing the external pagination and sort parameters The presence of this paginated list is
     * what determines if external pagination and sorting is used or not.
     */
    private PaginatedList paginatedList;

    /**
     * Is this the last iteration?
     * @return boolean <code>true</code> if this is the last iteration
     */
    protected boolean isLastIteration()
    {
        return this.lastIteration;
    }

    /**
     * Sets the list of parameter which should not be forwarded during sorting or pagination.
     * @param value whitespace separated list of parameters which should not be included (* matches all parameters)
     */
    public void setExcludedParams(String value)
    {
        this.excludedParams = value;
    }

    /**
     * Sets the content of the footer. Called by a nested footer tag.
     * @param string footer content
     */
    public void setFooter(String string)
    {
        this.footer = string;
        this.tableModel.setFooter(this.footer);
    }

    /**
     * Sets the content of the caption. Called by a nested caption tag.
     * @param string caption content
     */
    public void setCaption(String string)
    {
        this.caption = string;
        this.tableModel.setCaption(this.caption);
    }

    /**
     * Set the child caption tag.
     * @param captionTag Child caption tag
     */
    public void setCaptionTag(CaptionTag captionTag)
    {
        this.captionTag = captionTag;
    }

    /**
     * Obtain the child caption tag.
     * @return The child caption tag
     */
    public CaptionTag getCaptionTag()
    {
        return this.captionTag;
    }

    /**
     * Is the current row empty?
     * @return true if the current row is empty
     */
    protected boolean isEmpty()
    {
        return this.currentRow == null;
    }

    /**
     * set the Integer containing the total size of the data displaytag is paginating
     * @param size Integer containing the total size of the data
     */
    public void setSize(Object size)
    {
        if (size instanceof String)
        {
            this.sizeObjectName = (String) size;
        }
        else
        {
            this.size = size;
        }
    }

    /**
     * set the name of the Integer in some scope containing the total size of the data to be paginated
     * @param sizeObjectName name of the Integer containing the total size of the data to be paginated
     */
    public void setSizeObjectName(String sizeObjectName)
    {
        this.sizeObjectName = sizeObjectName;
    }

    /**
     * setter for the "sort" attribute.
     * @param value "page" (sort a single page) or "list" (sort the full list)
     * @throws InvalidTagAttributeValueException if value is not "page" or "list"
     */
    public void setSort(String value) throws InvalidTagAttributeValueException
    {
        if (TableTagParameters.SORT_AMOUNT_PAGE.equals(value))
        {
            this.sortFullTable = Boolean.FALSE;
        }
        else if (TableTagParameters.SORT_AMOUNT_LIST.equals(value))
        {
            this.sortFullTable = Boolean.TRUE;
        }
        else if (TableTagParameters.SORT_AMOUNT_EXTERNAL.equals(value))
        {
            this.localSort = false;
        }
        else
        {