net.sf.jasperreports.data.cache.ColumnDataSnapshot.java Source code

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Here is the source code for net.sf.jasperreports.data.cache.ColumnDataSnapshot.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.data.cache;

import java.io.IOException;
import java.io.Serializable;
import java.util.LinkedHashMap;
import java.util.Map;

import net.sf.jasperreports.engine.JRConstants;
import net.sf.jasperreports.engine.JRRuntimeException;
import net.sf.jasperreports.engine.data.IndexedDataSource;

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

/**
 * @author Lucian Chirita (lucianc@users.sourceforge.net)
 */
public class ColumnDataSnapshot implements DataSnapshot, Serializable {

    private static final Log log = LogFactory.getLog(ColumnDataSnapshot.class);

    public static final String EXCEPTION_MESSAGE_KEY_SNAPSHOT_CANNOT_BE_PERSISTED = "data.cache.snapshot.cannot.be.persisted";

    private static final long serialVersionUID = JRConstants.SERIAL_VERSION_UID;

    private Map<Object, ColumnCacheData> cachedData;
    private transient boolean persistable;

    public ColumnDataSnapshot() {
        cachedData = new LinkedHashMap<Object, ColumnCacheData>();
        persistable = true;
    }

    private void writeObject(java.io.ObjectOutputStream out) throws IOException {
        if (!persistable) {
            throw new JRRuntimeException(EXCEPTION_MESSAGE_KEY_SNAPSHOT_CANNOT_BE_PERSISTED, (Object[]) null);
        }

        out.defaultWriteObject();
    }

    private void readObject(java.io.ObjectInputStream in) throws IOException, ClassNotFoundException {
        this.persistable = true;

        in.defaultReadObject();
    }

    @Override
    public boolean hasCachedData(Object key) {
        return cachedData.containsKey(key);
    }

    @Override
    public CachedDataset getCachedData(Object key) throws DataSnapshotException {
        ColumnCacheData cacheData = cachedData.get(key);
        if (cacheData == null) {
            if (log.isDebugEnabled()) {
                log.debug("No cached data exists for " + key);
            }

            return null;
        }

        if (log.isDebugEnabled()) {
            log.debug("Found cached data source of " + cacheData.size() + " records for " + key);
        }

        IndexedDataSource dataSource = cacheData.createDataSource();

        Map<String, Object> parameters = cacheData.getParameters();
        StandardCachedDataset dataset = new StandardCachedDataset(dataSource, parameters);
        return dataset;
    }

    public void addCachedData(Object key, ColumnCacheData data) {
        cachedData.put(key, data);
    }

    @Override
    public boolean isPersistable() {
        return persistable;
    }

    public void setPersistable(boolean persistable) {
        this.persistable = persistable;
    }

}