reportgenerator.java

来自「swing编写的库存管理程序。毕业设计类」· Java 代码 · 共 250 行

/**
 * ========================================
 * 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.
 *
 * --------------------
 * ReportGenerator.java
 * --------------------
 * (C)opyright 2002, 2003, by Thomas Morgner and Contributors.
 *
 * Original Author:  Thomas Morgner;
 * Contributor(s):   David Gilbert (for Simba Management Limited);
 *
 * $Id: ReportGenerator.java,v 1.6.2.1 2003/12/21 23:28:46 taqua Exp $
 *
 * Changes
 * -------
 * 10-May-2002 : Initial version
 * 12-Dec-2002 : Fixed issues reported by Checkstyle (DG);
 *
 */

package org.jfree.report.modules.parser.base;

import java.io.File;
import java.io.IOException;
import java.net.URL;

import org.jfree.report.JFreeReport;
import org.jfree.report.util.ReportConfiguration;
import org.jfree.xml.ElementDefinitionException;
import org.jfree.xml.ParserFrontend;
import org.xml.sax.InputSource;

/**
 * The reportgenerator initializes the parser and provides an interface
 * the the default parser.
 *
 * To create a report from an URL, use
 * <code>
 * ReportGenerator.getInstance().parseReport (URL myURl, URL contentBase);
 * </code>
 *
 * @author Thomas Morgner
 */
public class ReportGenerator extends ParserFrontend
{
  /** Enable DTD validation of the parsed XML. */
  public static final String PARSER_VALIDATE
      = "org.jfree.report.modules.parser.base.Validate";

  /** disable DTD validation by default. */
  public static final String PARSER_VALIDATE_DEFAULT = "true";

  /** The report generator. */
  private static ReportGenerator generator;

  /**
   * Creates a new report generator. The generator uses the singleton pattern by
   * default, so use generator.getInstance() to get the generator.
   */
  protected ReportGenerator()
  {
    super(new ReportParser());
    initFromSystem();
  }

  /**
   * Tries to initilialize the generator by reading the system configuration.
   * This will enable the validation feature depending on the global configuration.
   */
  public void initFromSystem()
  {
    setEntityResolver(ParserEntityResolver.getDefaultResolver());
  }

  /**
   * Set to false, to globaly disable the xml-validation.
   *
   * @param validate true, if the parser should validate the xml files.
   */
  public void setValidateDTD(final boolean validate)
  {
    ReportConfiguration.getGlobalConfig().setConfigProperty
        (PARSER_VALIDATE, String.valueOf(validate));
  }

  /**
   * returns true, if the parser should validate the xml files against the DTD
   * supplied with JFreeReport.
   *
   * @return true, if the parser should validate, false otherwise.
   */
  public boolean isValidateDTD()
  {
    return ReportConfiguration.getGlobalConfig().getConfigProperty
        (PARSER_VALIDATE, PARSER_VALIDATE_DEFAULT).equalsIgnoreCase("true");
  }


  /**
   * Parses a report using the given parameter as filename and the directory
   * containing the file as content base.
   *
   * @param file  the file name.
   *
   * @return the report.
   *
   * @throws java.io.IOException if an I/O error occurs.
   * @throws org.jfree.xml.ElementDefinitionException if there is a problem parsing the
   * report template.
   */
  public JFreeReport parseReport(final String file)
      throws IOException, ElementDefinitionException
  {
    if (file == null)
    {
      throw new NullPointerException("File may not be null");
    }

    return parseReport(new File(file));
  }

  /**
   * Parses an XML file which is loaded using the given URL. All
   * needed relative file- and resourcespecification are loaded
   * using the URL <code>file</code> as base.
   *
   * @param file  the URL for the report template file.
   *
   * @return the report.
   *
   * @throws java.io.IOException if an I/O error occurs.
   * @throws org.jfree.xml.ElementDefinitionException if there is a problem parsing
   * the report template.
   */
  public JFreeReport parseReport(final URL file)
      throws ElementDefinitionException, IOException
  {
    return parseReport(file, file);
  }

  /**
   * Parses an XML file which is loaded using the given URL. All
   * needed relative file- and resourcespecification are loaded
   * using the URL <code>contentBase</code> as base.
   * <p>
   * After the report is generated, the ReportDefinition-source and the
   * contentbase are stored as string in the reportproperties.
   *
   * @param file  the URL for the report template file.
   * @param contentBase  the URL for the report template content base.
   *
   * @return the parsed report.
   *
   * @throws java.io.IOException if an I/O error occurs.
   * @throws org.jfree.xml.ElementDefinitionException if there is a problem parsing
   * the report template.
   */
  public JFreeReport parseReport(final URL file, final URL contentBase)
      throws ElementDefinitionException, IOException
  {
    final JFreeReport report = (JFreeReport) parse(file, contentBase);
    report.setProperty(JFreeReport.REPORT_DEFINITION_SOURCE, file.toString());
    if (contentBase != null)
    {
      report.setProperty
          (JFreeReport.REPORT_DEFINITION_CONTENTBASE, contentBase.toString());
    }
    else
    {
      report.setProperty
          (JFreeReport.REPORT_DEFINITION_CONTENTBASE, file.toString());
    }
    return report;
  }

  /**
   * Parses an XML file which is loaded using the given file. All
   * needed relative file- and resourcespecification are loaded
   * using the parent directory of the file <code>file</code> as base.
   *
   * @param file  the report template file.
   *
   * @return the parsed report.
   *
   * @throws java.io.IOException if an I/O error occurs.
   * @throws org.jfree.xml.ElementDefinitionException if there is a problem parsing
   * the report template.
   */
  public JFreeReport parseReport(final File file)
      throws IOException, ElementDefinitionException
  {
    if (file == null)
    {
      throw new NullPointerException();
    }

    final File contentBase = file.getCanonicalFile().getParentFile();
    return parseReport(file.toURL(), contentBase.toURL());
  }

  /**
   * Parses an XML report template file.
   *
   * @param input  the input source.
   * @param contentBase  the content base.
   *
   * @return the report.
   *
   * @throws org.jfree.xml.ElementDefinitionException if an error occurred.
   */
  public JFreeReport parseReport(final InputSource input, final URL contentBase)
      throws ElementDefinitionException
  {
    return (JFreeReport) super.parse(input, contentBase);
  }

  /**
   * Returns a single shared instance of the <code>ReportGenerator</code>.
   *
   * @return The shared report generator.
   */
  public static ReportGenerator getInstance()
  {
    if (generator == null)
    {
      generator = new ReportGenerator();
    }
    return generator;
  }
}