Application: gvSIG desktop

/**

 * gvSIG. Desktop Geographic Information System.

 *

 * Copyright (C) 2007-2013 gvSIG Association.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 3

 * of the License, or (at your option) any later version.

 *

 * This program 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 General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 * For any additional information, do not hesitate to contact us

 * at info AT gvsig.com, or visit our website www.gvsig.com.

 */

package org.gvsig.app.project.documents.actions;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.Iterator;

import java.util.List;

import java.util.Map;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.gvsig.andami.PluginsLocator;

import org.gvsig.app.project.documents.Document;

import org.gvsig.tools.ToolsLocator;

import org.gvsig.tools.persistence.PersistenceManager;

import org.gvsig.tools.persistence.PersistentState;

import org.gvsig.tools.persistence.exception.PersistenceException;

/**

 * This class provides utility methods to manage the clipboard

 * for documents (it's file-based, it's not the system clipboard)

 * which will contain one or more documents for copy/cut/paste

 * operations. It is currently implemented using persistence

 * 

 * Each document type uses it's own "clipboard". Some actions

 * can affect all those clipboards at the same time

 * 

 * @author jldominguez

 * 

 */

public class CopyPasteDocsUtils {

    private static Logger logger = LoggerFactory

        .getLogger(CopyPasteDocsUtils.class);

    /**

     * The folder where docs are temporarily persisted

     */

    private static File clipboardFolder = null;

    private static String CLIPBOARD_FILE_NAME_PREFIX = "gvSIG_docs_clipboard_";

    private static String CLIPBOARD_FILE_NAME_EXTENSION = "tmp";

    private static int MAX_FILE_COUNT = 1000;

    private CopyPasteDocsUtils() {

    }

    private static PersistenceManager getPersMan() {

        return ToolsLocator.getPersistenceManager();

    }

    private static File getClipboardFolder() {

        if (clipboardFolder == null) {

            File appf = PluginsLocator.getManager().getApplicationHomeFolder();

            clipboardFolder = new File(appf, "clipboard-documents");

            clipboardFolder.mkdirs();

        }

        return clipboardFolder;

    }

    /**

     * Gets all if parameter is null

     * 

     */

    public static List<File> getClipboardFiles(String typeName) {

        List<File> resp = new ArrayList<File>();

        String filebase = CLIPBOARD_FILE_NAME_PREFIX;

        if (typeName != null) {

            filebase = filebase + typeName;

        }

        File folder = getClipboardFolder();

        if (!folder.exists() || !folder.isDirectory()) {

            return resp;

        }

        File[] ff = folder.listFiles();

        for (int i=0; i<ff.length; i++) {

            if (ff[i].getName().startsWith(filebase)) {

                resp.add(ff[i]);

            }

        }

        return resp;

    }

    private static File getFirstUnusedClipboardFile(String docTypeName)

    throws IOException {

        if (docTypeName == null || docTypeName.length() == 0) {

            throw new IOException("Doc type name cannot be empty");

        }

        String filename = null;

        for (int i=0; i<MAX_FILE_COUNT; i++) {

            filename = CLIPBOARD_FILE_NAME_PREFIX + docTypeName + "_" +

                Integer.toString(i)

                + "." + CLIPBOARD_FILE_NAME_EXTENSION;

            File resp = new File(getClipboardFolder(), filename);

            if (!resp.exists()) {

                /*

                 * Removed when JVM terminates

                 */

                resp.deleteOnExit();

                return resp;

            }

        }

        // This should never happen

        throw new IOException("Clipboard is full for documents: " + docTypeName);

    }

    /**

     * Clears clipboard of the provided doc type,

     * or clears all document clipboard if parameter is null.

     * 

     * @param docTypeName

     */

    public static void clearClipboard(String docTypeName) throws IOException {

        String filebase = CLIPBOARD_FILE_NAME_PREFIX;

        if (docTypeName != null) {

            filebase = filebase + docTypeName;

        }

        File folder = getClipboardFolder();

        if (!folder.exists() || !folder.isDirectory()) {

            /*

             * Nothing to do

             */

            return;

        }

        File[] ff = folder.listFiles();

        Exception exc = null;

        for (int i=0; i<ff.length; i++) {

            if (ff[i].getName().startsWith(filebase)) {

                try {

                    ff[i].delete();

                } catch (Exception e) {

                    // Keep first exception and try to go on

                    if (exc == null) {

                        exc = e;

                    }

                }

            }

        }

        // =================================

        if (exc != null) {

            throw new IOException(exc.getMessage());

        }

    }

    /**

     * Returns the content of the clipboard as a list of

     * documents or null if clipboard is empty or does not

     * contain documents of the specified type

     * 

     * 

     * 

     * @return

     * @throws PersistenceException

     */

    public static List<Document> getClipboardDocuments(String typeName)

        throws IOException, PersistenceException {

        List<Document> resp = new ArrayList<Document>();

        List<File> ff = getClipboardFiles(typeName);

        File infile = null;

        InputStream is = null;

        Object obj = null;

        Document doc = null;

        for (int i=0; i<ff.size(); i++) {

            infile = ff.get(i);

            is = new FileInputStream(infile);

            obj = getPersMan().getObject(is);

            is.close();

            if (obj instanceof Document) {

                doc = (Document) obj;

                // Checking, but it should not be necessary

                if (typeName == null || doc.getTypeName().compareTo(typeName) == 0) {

                    resp.add(doc);

                }

            }

        }

        return resp;

    }

    /**

     * Stores doc list to their clipboard

     * to clipboard

     * 

     * @param st

     * @throws PersistenceException

     */

    public static void saveToClipboard(List<Document> docs)

        throws IOException, PersistenceException {

        if (docs == null || docs.size() == 0) {

            return;

        }

        Map<String, List<Document>> separ =

            new HashMap<String, List<Document>>();

        Document doc = null;

        List<Document> list = null;

        for (int i=0; i<docs.size(); i++) {

            doc = docs.get(i);

            if (doc != null && doc.getTypeName() != null) {

                list = separ.get(doc.getTypeName());

                if (list == null) {

                    list = new ArrayList<Document>();

                    list.add(doc);

                    separ.put(doc.getTypeName(), list);

                } else {

                    list.add(doc);

                }

            }

        }

        Iterator<String> iter = separ.keySet().iterator();

        String k = null;

        while (iter.hasNext()) {

            k = iter.next();

            saveToClipboard(k, separ.get(k));

        }

    }

    /**

     * docs in list are of same type

     * @param typeName

     * @param docs

     */

    private static void saveToClipboard(String typeName, List<Document> docs)

    throws IOException, PersistenceException {

        clearClipboard(typeName);

        File f = null;

        OutputStream os = null;

        PersistentState state = null;

        for (int i=0; i<docs.size(); i++) {

            state = getPersMan().getState(docs.get(i), true);

            if (state.getContext().getErrors() != null) {

                throw state.getContext().getErrors();

            }

            f = getFirstUnusedClipboardFile(typeName);

            os = new FileOutputStream(f);

            getPersMan().saveState(state, os);

            os.close();

        }

    }

    public static String getLastMessage(Throwable ex) {

        if (ex == null) {

            return "-";

        }

        Throwable p = ex;

        while (p.getCause() != null && p.getCause() != p) {

            p = p.getCause();

        }

        return p.getMessage();

    }

}