simplepagelayouter.java

Java的Web报表库

/**
 * ========================================
 * JFreeReport : a free Java report library
 * ========================================
 *
 * Project Info:  http://www.jfree.org/jfreereport/index.html
 * Project Lead:  Thomas Morgner;
 *
 * (C) Copyright 2000-2003, by Simba Management Limited and Contributors.
 *
 * This library is free software; you can redistribute it and/or modify it under the terms
 * of the GNU Lesser General Public License as published by the Free Software Foundation;
 * either version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this
 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * -----------------------
 * SimplePageLayouter.java
 * -----------------------
 * (C)opyright 2002, 2003, by Thomas Morgner and Contributors.
 *
 * Original Author:  Thomas Morgner;
 * Contributor(s):   David Gilbert (for Simba Management Limited);
 *
 * $Id: SimplePageLayouter.java,v 1.55.2.2 2003/08/24 14:18:13 taqua Exp $
 *
 * Changes
 * -------
 * 05-Dec-2002 : Updated Javadocs (DG);
 * 07-Dec-2002 : Removed manual-pagebreak flag, was a left-over. PageFinished
 *               did not query the DISPLAY_ON_FIRSTPAGE flag.
 * 12-Dec-2002 : Layouting Fix    I: Layouting failed for non-absolute band elements if no
 *               absolute positioned elements were defined.
 * 18-Dec-2002 : Layouting Fix  II: PageFooter on own page failed
 * 07-Jan-2003 : Layouting Fix III: Limited max band height to the available space of a single page
 * 08-Jan-2003 : Layouting Fix IIa: PageFooter fix fix
 * 27-Jan-2003 : BugFix: printing empty bands caused a commit spooled operations
 * 01-Feb-2003 : Layouting moved into BandLayoutManagerUtil (Common code)
 */

package com.jrefinery.report.targets.pageable.pagelayout;

import java.awt.geom.Rectangle2D;

import com.jrefinery.report.Band;
import com.jrefinery.report.Group;
import com.jrefinery.report.JFreeReportConstants;
import com.jrefinery.report.ReportProcessingException;
import com.jrefinery.report.states.DataRowConnector;
import com.jrefinery.report.states.ReportDefinitionImpl;
import com.jrefinery.report.event.PrepareEventListener;
import com.jrefinery.report.event.ReportEvent;
import com.jrefinery.report.function.Expression;
import com.jrefinery.report.function.FunctionProcessingException;
import com.jrefinery.report.states.ReportState;
import com.jrefinery.report.targets.base.bandlayout.BandLayoutManagerUtil;
import com.jrefinery.report.targets.pageable.LogicalPage;
import com.jrefinery.report.targets.pageable.OutputTargetException;
import com.jrefinery.report.targets.pageable.Spool;
import com.jrefinery.report.targets.style.BandStyleSheet;

/**
 * A simple page layouter.  This class replicates the 'old' behaviour of JFreeReport,
 * simple and straightforward.
 * <p>
 * Layout Constraints used:
 * <ul>
 * <li>PageHeader, PageFooter: BandStyleSheet.DISPLAY_ON_FIRST_PAGE
 * <p>Defines whether a PageHeader or ~footer should be printed on the first page.</p>
 * <li>PageHeader, PageFooter: BandStyleSheet.DISPLAY_ON_LAST_PAGE
 * <p>Defines whether a PageHeader or ~footer should be printed on the last page.
 * A warning: For the PageHeader this works only if the ReportFooter has a pagebreak
 * before printing.
 * </p>
 * <li>GroupHeader: BandStyleSheet.REPEAT_HEADER
 * <p>Defines whether this GroupHeader should be repeated on every page as long as this
 * group is active</p>
 * <li>All Bands: BandStyleSheet.PAGEBREAK_BEFORE, BandStyleSheet.PAGEBREAK_AFTER
 * <p>defines whether to start a new page before the band is printed or after the
 * band is printed. This request is ignored, if the current page is empty (not counting
 * the PageHeader and the repeating GroupHeader).</p>
 * </ul>
 *
 * @author Thomas Morgner
 */
public class SimplePageLayouter extends PageLayouter implements PrepareEventListener
{
  /**
   * Represents the current state of the page layouter.
   */
  protected static class SimpleLayoutManagerState extends PageLayouter.LayoutManagerState
  {
    /** The band. */
    private Band band;

    /**
     * Creates a new state.  The band can be <code>null</code> if there is no band to be printed
     * on the next page.
     *
     * @param band  the band.
     */
    public SimpleLayoutManagerState(final Band band)
    {
      this.band = band;
    }

    /**
     * Returns the band.
     *
     * @return the band.
     */
    public Band getBand()
    {
      return band;
    }

    /**
     * Returns a string describing the object.
     *
     * @return The string.
     */
    public String toString()
    {
      return "State={" + band + "}";
    }
  }

  /** small carrier class to transport the maximum page number for this report. */
  private static class PageCarrier
  {
    /** stores the last page number of the report processing. */
    public int maxPages;
  }

  /** the page carrier for this pagelayouter contains the number of the last page. */
  private PageCarrier pageCarrier;

  /** A useful constant. */
  private static final boolean ENDPAGE_FORCED = true;

  /** A useful constant. */
  private static final boolean ENDPAGE_REQUESTED = false;

  /** A flag that indicates that the current pagebreak will be the last one. */
  private boolean isLastPageBreak;

  /**
   * A flag which indicates that a new page should be started before the next band
   * is printed. Bool-or this flag with PageBreakBefore ...
   */
  private boolean startNewPage;

  /** The cursor used by the layouter. */
  private SimplePageLayoutCursor cursor;

  /** The current state. */
  private SimpleLayoutManagerState state;

  /** The spool. */
  private Spool spooledBand;

  /** The current state for repeating group headers. */
  private int currentEffectiveGroupIndex;

  /**
   * Creates a new page layouter.
   */
  public SimplePageLayouter()
  {
    setName("Layout");
    currentEffectiveGroupIndex = -1;
    pageCarrier = new PageCarrier();
  }

  /**
   * Return a completly separated copy of this function. The copy does no
   * longer share any changeable objects with the original function.
   *
   * @return a copy of this function.
   */
  public Expression getInstance()
  {
    final SimplePageLayouter pl = (SimplePageLayouter) super.getInstance();
    pl.pageCarrier = new PageCarrier();
    return pl;
  }

  /**
   * Returns the highest pagenumber found during the repagination process.
   *
   * @return the highest page number.
   */
  public int getMaxPage()
  {
    return pageCarrier.maxPages;
  }

  /**
   * Defines the highest pagenumber found during the repagination process.
   *
   * @param maxPage the highest page number.
   */
  protected void setMaxPage(final int maxPage)
  {
    pageCarrier.maxPages = maxPage;
  }

  /**
   * Receives notification that the report has started. Also invokes the
   * start of the first page ...
   * <P>
   * Layout and draw the report header after the PageStartEvent was fired.
   *
   * @param event  the event.
   */
  public void reportStarted(final ReportEvent event)
  {
    // activating this state after the page has ended is invalid.
    if (isPageEnded())
    {
      throw new IllegalStateException();
    }
    setCurrentEvent(event);
    if (getCurrentEvent() == null)
    {
      throw new NullPointerException("getCurrentEvent() returned null");
    }
    try
    {
      currentEffectiveGroupIndex = -1;
      printBand(getReport().getReportHeader());
    }
    catch (FunctionProcessingException fe)
    {
      throw fe;
    }
    catch (Exception e)
    {
      throw new FunctionProcessingException("ReportStarted failed", e);
    }
    finally
    {
      clearCurrentEvent();
    }
  }

  /**
   * Receives notification that a group of item bands has been completed.
   * <P>
   * The itemBand is finished, the report starts to close open groups.
   *
   * @param event The event.
   */
  public void itemsFinished(final ReportEvent event)
  {
    // activating this state after the page has ended is invalid.
    if (isPageEnded())
    {
      throw new IllegalStateException();
    }
    currentEffectiveGroupIndex -= 1;
  }

  /**
   * Receives notification that report generation has completed, the report footer was printed,
   * no more output is done. This is a helper event to shut down the output service.
   *
   * @param event The event.
   */
  public void reportDone(final ReportEvent event)
  {
    // activating this state after the page has ended is invalid.
    if (isPageEnded())
    {
      throw new IllegalStateException();
    }
    try
    {
      setCurrentEvent(event);
      restartPage();
      createSaveState(null);
      saveCurrentState();

      endPage(ENDPAGE_FORCED);
    }
    catch (Exception e)
    {
      throw new FunctionProcessingException("ReportDone", e);
    }
    finally
    {
      clearCurrentEvent();
    }
  }

  /**
   * Receives notification that a group of item bands is about to be processed.
   * <P>
   * The next events will be itemsAdvanced events until the itemsFinished event is raised.
   *
   * @param event The event.
   */
  public void itemsStarted(final ReportEvent event)
  {
    // activating this state after the page has ended is invalid.
    if (isPageEnded())
    {
      throw new IllegalStateException();
    }
    currentEffectiveGroupIndex += 1;
  }

  /**
   * Receives notification that a page has started.
   * <P>
   * This prints the PageHeader. If this is the first page, the header is not
   * printed if the pageheader style-flag DISPLAY_ON_FIRSTPAGE is set to false.
   * If this event is known to be the last pageStarted event, the DISPLAY_ON_LASTPAGE
   * is evaluated and the header is printed only if this flag is set to TRUE.
   * <p>
   * If there is an active repeating GroupHeader, print the last one. The GroupHeader
   * is searched for the current group and all parent groups, starting at the
   * current group and ascending to the parents. The first goupheader that has the
   * StyleFlag REPEAT_HEADER set to TRUE is printed.
   * <p>
   * The PageHeader and the repeating GroupHeader are spooled until the first real
   * content is printed. This way, the LogicalPage remains empty until an other band
   * is printed.
   *
   * @param event Information about the event.
   */
  public void pageStarted(final ReportEvent event)
  {
    // activating this state after the page has ended is invalid.
    if (isPageEnded())
    {
      throw new IllegalStateException();
    }
    setCurrentEvent(event);
    try
    {
      // a new page has started, so reset the cursor ...
      setCursor(new SimplePageLayoutCursor(getLogicalPage().getHeight()));

      final Band b = getReport().getPageHeader();
      if (event.getState().getCurrentPage() == 1)
      {
        if (b.getStyle().getBooleanStyleProperty(BandStyleSheet.DISPLAY_ON_FIRSTPAGE) == true)
        {
          print(b, true);
        }
      }
      else if (event.getState().getCurrentPage() == getMaxPage())
      {
        if (b.getStyle().getBooleanStyleProperty(BandStyleSheet.DISPLAY_ON_LASTPAGE) == true)
        {
          print(b, true);
        }
      }
      else if (isLastPageBreak)
      {
        if (b.getStyle().getBooleanStyleProperty(BandStyleSheet.DISPLAY_ON_LASTPAGE) == true)
        {
          print(b, true);
        }
      }
      else
      {
        print(b, true);
      }