net.sf.jasperreports.engine.export.GenericElementReportTransformer.java Source code

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Here is the source code for net.sf.jasperreports.engine.export.GenericElementReportTransformer.java

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/*
 * JasperReports - Free Java Reporting Library.
 * Copyright (C) 2001 - 2019 TIBCO Software Inc. All rights reserved.
 * http://www.jaspersoft.com
 *
 * Unless you have purchased a commercial license agreement from Jaspersoft,
 * the following license terms apply:
 *
 * This program is part of JasperReports.
 *
 * JasperReports 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 3 of the License, or
 * (at your option) any later version.
 *
 * JasperReports 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 JasperReports. If not, see <http://www.gnu.org/licenses/>.
 */
package net.sf.jasperreports.engine.export;

import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import net.sf.jasperreports.engine.JRGenericPrintElement;
import net.sf.jasperreports.engine.JRPrintElement;
import net.sf.jasperreports.engine.JRPrintFrame;
import net.sf.jasperreports.engine.JRPrintPage;
import net.sf.jasperreports.engine.JasperPrint;
import net.sf.jasperreports.engine.JasperReportsContext;

/**
 * A utility class that applies {@link GenericElementTransformer GenericElementTransformers}
 * to a filled report.
 * 
 * @author Lucian Chirita (lucianc@users.sourceforge.net)
 * @see GenericElementTransformer
 */
public final class GenericElementReportTransformer {
    private static final Log log = LogFactory.getLog(GenericElementReportTransformer.class);

    protected static class TransformerContext implements GenericElementTransformerContext {
        private final JasperReportsContext jasperReportsContext;
        private final JasperPrint report;

        public TransformerContext(JasperReportsContext jasperReportsContext, JasperPrint report) {
            this.jasperReportsContext = jasperReportsContext;
            this.report = report;
        }

        @Override
        public JasperReportsContext getJasperReportsContext() {
            return jasperReportsContext;
        }

        @Override
        public JasperPrint getReport() {
            return report;
        }
    }

    /**
     * Applies generic element transformers of a specific key to a filled report
     * by replacing generic elements with the transformed elements.
     * 
     * @param report the report
     * @param transformerExportKey the key used to resolve element transformers
     * @see GenericElementTransformer
     * @see GenericElementHandlerBundle#getHandler(String, String)
     */
    public static void transformGenericElements(JasperReportsContext jasperReportsContext, JasperPrint report,
            String transformerExportKey) {
        TransformerContext transformerContext = new TransformerContext(jasperReportsContext, report);
        List<JRPrintPage> pages = report.getPages();
        for (Iterator<JRPrintPage> pageIt = pages.iterator(); pageIt.hasNext();) {
            JRPrintPage page = pageIt.next();
            transformElements(transformerContext, transformerExportKey, page.getElements());
        }
    }

    protected static void transformElements(TransformerContext context, String transformerExportKey,
            List<JRPrintElement> elements) {
        for (ListIterator<JRPrintElement> it = elements.listIterator(); it.hasNext();) {
            JRPrintElement element = it.next();
            if (element instanceof JRGenericPrintElement) {
                JRGenericPrintElement genericElement = (JRGenericPrintElement) element;
                GenericElementTransformer handler = (GenericElementTransformer) GenericElementHandlerEnviroment
                        .getInstance(context.getJasperReportsContext())
                        .getElementHandler(genericElement.getGenericType(), transformerExportKey);
                if (handler != null && handler.toExport(genericElement)) {
                    JRPrintElement transformed = handler.transformElement(context, genericElement);

                    if (log.isDebugEnabled()) {
                        log.debug("Transformed element " + genericElement + " to " + transformed + " using the "
                                + transformerExportKey + " transformer");
                    }

                    // assuming that the list is modifiable
                    it.set(transformed);
                }
            } else if (element instanceof JRPrintFrame) {
                JRPrintFrame frame = (JRPrintFrame) element;
                transformElements(context, transformerExportKey, frame.getElements());
            }
        }

    }

    private GenericElementReportTransformer() {
    }
}