001// License: GPL. For details, see LICENSE file. 002package org.openstreetmap.josm.io; 003 004import static org.openstreetmap.josm.tools.I18n.tr; 005 006import java.io.File; 007import java.io.FileNotFoundException; 008import java.io.IOException; 009import java.io.OutputStream; 010import java.io.OutputStreamWriter; 011import java.io.PrintWriter; 012import java.io.Writer; 013import java.nio.charset.StandardCharsets; 014import java.text.MessageFormat; 015 016import javax.swing.JOptionPane; 017 018import org.openstreetmap.josm.Main; 019import org.openstreetmap.josm.actions.ExtensionFileFilter; 020import org.openstreetmap.josm.gui.layer.Layer; 021import org.openstreetmap.josm.gui.layer.OsmDataLayer; 022import org.openstreetmap.josm.tools.Utils; 023 024/** 025 * Exports data to an .osm file. 026 * @since 1949 027 */ 028public class OsmExporter extends FileExporter { 029 030 /** 031 * Constructs a new {@code OsmExporter}. 032 */ 033 public OsmExporter() { 034 super(OsmImporter.FILE_FILTER); 035 } 036 037 /** 038 * Constructs a new {@code OsmExporter}. 039 * @param filter The extension file filter 040 */ 041 public OsmExporter(ExtensionFileFilter filter) { 042 super(filter); 043 } 044 045 @Override 046 public boolean acceptFile(File pathname, Layer layer) { 047 if (!(layer instanceof OsmDataLayer)) 048 return false; 049 return super.acceptFile(pathname, layer); 050 } 051 052 @Override 053 public void exportData(File file, Layer layer) throws IOException { 054 exportData(file, layer, false); 055 } 056 057 /** 058 * Exports OSM data to the given file. 059 * @param file Output file 060 * @param layer Data layer. Must be an instance of {@link OsmDataLayer}. 061 * @param noBackup if {@code true}, the potential backup file created if the output file already exists will be deleted 062 * after a successful export 063 * @throws IllegalArgumentException if {@code layer} is not an instance of {@code OsmDataLayer} 064 */ 065 public void exportData(File file, Layer layer, boolean noBackup) { 066 checkOsmDataLayer(layer); 067 save(file, (OsmDataLayer) layer, noBackup); 068 } 069 070 protected static void checkOsmDataLayer(Layer layer) { 071 if (!(layer instanceof OsmDataLayer)) { 072 throw new IllegalArgumentException(MessageFormat.format("Expected instance of OsmDataLayer. Got ''{0}''.", layer 073 .getClass().getName())); 074 } 075 } 076 077 protected static OutputStream getOutputStream(File file) throws FileNotFoundException, IOException { 078 return Compression.getCompressedFileOutputStream(file); 079 } 080 081 private void save(File file, OsmDataLayer layer, boolean noBackup) { 082 File tmpFile = null; 083 try { 084 // use a tmp file because if something errors out in the 085 // process of writing the file, we might just end up with 086 // a truncated file. That can destroy lots of work. 087 if (file.exists()) { 088 tmpFile = new File(file.getPath() + '~'); 089 Utils.copyFile(file, tmpFile); 090 } 091 092 doSave(file, layer); 093 if (noBackup || !Main.pref.getBoolean("save.keepbackup", false)) { 094 if (tmpFile != null) { 095 Utils.deleteFile(tmpFile); 096 } 097 } 098 layer.onPostSaveToFile(); 099 } catch (IOException e) { 100 Main.error(e); 101 JOptionPane.showMessageDialog( 102 Main.parent, 103 tr("<html>An error occurred while saving.<br>Error is:<br>{0}</html>", e.getMessage()), 104 tr("Error"), 105 JOptionPane.ERROR_MESSAGE 106 ); 107 108 try { 109 // if the file save failed, then the tempfile will not 110 // be deleted. So, restore the backup if we made one. 111 if (tmpFile != null && tmpFile.exists()) { 112 Utils.copyFile(tmpFile, file); 113 } 114 } catch (IOException e2) { 115 Main.error(e2); 116 JOptionPane.showMessageDialog( 117 Main.parent, 118 tr("<html>An error occurred while restoring backup file.<br>Error is:<br>{0}</html>", e2.getMessage()), 119 tr("Error"), 120 JOptionPane.ERROR_MESSAGE 121 ); 122 } 123 } 124 } 125 126 protected void doSave(File file, OsmDataLayer layer) throws IOException, FileNotFoundException { 127 // create outputstream and wrap it with gzip or bzip, if necessary 128 try ( 129 OutputStream out = getOutputStream(file); 130 Writer writer = new OutputStreamWriter(out, StandardCharsets.UTF_8); 131 OsmWriter w = OsmWriterFactory.createOsmWriter(new PrintWriter(writer), false, layer.data.getVersion()); 132 ) { 133 layer.data.getReadLock().lock(); 134 try { 135 w.writeLayer(layer); 136 } finally { 137 layer.data.getReadLock().unlock(); 138 } 139 } 140 } 141}