--- /dev/null
+package org.simantics.databoard.container;\r
+\r
+import java.io.DataInput;\r
+import java.io.DataInputStream;\r
+import java.io.DataOutput;\r
+import java.io.File;\r
+import java.io.FileInputStream;\r
+import java.io.IOException;\r
+import java.io.InputStream;\r
+import java.util.Map;\r
+import java.util.TreeMap;\r
+\r
+import org.simantics.databoard.Bindings;\r
+import org.simantics.databoard.binding.Binding;\r
+import org.simantics.databoard.binding.impl.TreeMapBinding;\r
+import org.simantics.databoard.binding.mutable.Variant;\r
+import org.simantics.databoard.serialization.Serializer;\r
+import org.simantics.databoard.type.Datatype;\r
+import org.simantics.databoard.util.binary.BinaryFile;\r
+\r
+/**\r
+ * An utility class for reading files whose format follows\r
+ * {@link DataContainer}.\r
+ * @author Hannu Niemistö\r
+ */\r
+public class DataContainers {\r
+\r
+ private static final Serializer STRING_SERIALIZER = \r
+ Bindings.getSerializerUnchecked(Bindings.STRING);\r
+ private static final Serializer INTEGER_SERIALIZER = \r
+ Bindings.getSerializerUnchecked(Bindings.INTEGER);\r
+ private static final Serializer METADATA_SERIALIZER = \r
+ Bindings.getSerializerUnchecked(new TreeMapBinding(Bindings.STRING, Bindings.VARIANT));\r
+ private static final Serializer DATATYPE_SERIALIZER =\r
+ Bindings.getSerializerUnchecked(Datatype.class);\r
+ private static final Serializer VARIANT_SERIALIZER =\r
+ Bindings.getSerializerUnchecked(Bindings.VARIANT);\r
+ private static final Serializer DATA_CONTAINER_SERIALIZER =\r
+ Bindings.getSerializerUnchecked(DataContainer.class);\r
+\r
+ /**\r
+ * Binds a format name and a version together to form a format version\r
+ * identifier string.\r
+ * \r
+ * @param formatName\r
+ * @param version\r
+ * @return\r
+ */\r
+ public static String toFormatString(String formatName, int version) {\r
+ return formatName + ":" + version;\r
+ }\r
+\r
+ /**\r
+ * Reads only the header of the data container. Returns\r
+ * a DataContainer whose content-field is null.\r
+ * @throws IOException \r
+ */\r
+ public static DataContainer readHeader(DataInput input) throws IOException {\r
+ String format = (String)STRING_SERIALIZER.deserialize(input);\r
+ int version = (Integer)INTEGER_SERIALIZER.deserialize(input);\r
+ @SuppressWarnings("unchecked")\r
+ TreeMap<String,Variant> metadata = (TreeMap<String,Variant>)METADATA_SERIALIZER.deserialize(input); \r
+ return new DataContainer(format, version, metadata, null);\r
+ }\r
+ \r
+ /**\r
+ * Consumes a header from a given stream and checks that the header satisfies the given format and version.\r
+ * Returns the obtained header if the check fails and null on success.\r
+ * @throws IOException \r
+ */\r
+ public static DataContainer requireHeader(DataInput input, String format, int version) {\r
+ try {\r
+ DataContainer header = readHeader(input);\r
+ if(!format.equals(header.format) || version != header.version)\r
+ return header;\r
+ else return null;\r
+ } catch (Throwable t) {\r
+ return new DataContainer("unknown", 0, null, null);\r
+ }\r
+ }\r
+\r
+ /**\r
+ * Consumes a header from a given stream and checks that the header satisfies the given format and version restrictions.\r
+ * Returns the obtained header if the check fails and null on success.\r
+ * @throws IOException \r
+ */\r
+ public static DataContainer requireHeader(DataInput input, String... requiredFormatStrings) {\r
+ try {\r
+ DataContainer header = readHeader(input);\r
+ String formatString = toFormatString(header.format, header.version);\r
+ for (String requiredFormatString : requiredFormatStrings) {\r
+ if(formatString.equals(requiredFormatString))\r
+ return null;\r
+ }\r
+ return header;\r
+ } catch (Throwable t) {\r
+ return new DataContainer("unknown", 0, null, null);\r
+ }\r
+ }\r
+\r
+ /**\r
+ * Checks that the given file satisfies the given format and version. \r
+ * Returns the obtained header if the check fails and null on success.\r
+ * @throws IOException \r
+ */\r
+ public static DataContainer validateHeader(File file, String format, int version) throws IOException {\r
+\r
+ InputStream stream = new FileInputStream( file );\r
+ try {\r
+ return DataContainers.requireHeader(new DataInputStream(stream), format, version);\r
+ } finally {\r
+ stream.close();\r
+ }\r
+ \r
+ }\r
+\r
+ /**\r
+ * Checks that the given file satisfies the given format and version. \r
+ * Returns the obtained header if the check fails and null on success.\r
+ * @throws IOException \r
+ */\r
+ public static DataContainer validateHeader(File file, String... allowedFormatStrings) throws IOException {\r
+\r
+ InputStream stream = new FileInputStream( file );\r
+ try {\r
+ return DataContainers.requireHeader(new DataInputStream(stream), allowedFormatStrings);\r
+ } finally {\r
+ stream.close();\r
+ }\r
+ \r
+ }\r
+\r
+ /**\r
+ * Reads only the header of the data container. Returns\r
+ * a DataContainer whose content-field is null.\r
+ * @throws IOException \r
+ */\r
+ public static DataContainer readHeader(File input) throws IOException {\r
+ BinaryFile rf = new BinaryFile( input, "r" );\r
+ try {\r
+ return readHeader(rf);\r
+ } finally {\r
+ rf.close();\r
+ } \r
+ }\r
+ \r
+ /**\r
+ * Reads a data container including the content data.\r
+ * @throws IOException \r
+ */\r
+ public static DataContainer readFile(DataInput input) throws IOException {\r
+ DataContainer result = readHeader(input);\r
+ result.content = (Variant)VARIANT_SERIALIZER.deserialize(input);\r
+ return result;\r
+ }\r
+\r
+ /**\r
+ * Process a data container using a format handler matching the format and version\r
+ * of the file. \r
+ * @param handlers Map of handlers. Keys are strings of form "format:version".\r
+ */\r
+ public static <T> T readFile(DataInput input, Map<String, FormatHandler<T>> handlers) throws Exception {\r
+ DataContainer result = readHeader(input);\r
+ \r
+ FormatHandler<T> handler = handlers.get(result.format + ":" + result.version);\r
+ if(handler == null)\r
+ throw new DataFormatException("Unknown data format " + result.format + " version " + result.version + ".");\r
+ Binding binding = handler.getBinding();\r
+ \r
+ Datatype contentType = (Datatype)DATATYPE_SERIALIZER.deserialize(input);\r
+ if(!binding.type().equals(contentType))\r
+ throw new DataFormatException("Content type didn't match the type expected for the format " + result.format + " version " + result.version + ".");\r
+ \r
+ Object value = Bindings.getSerializerUnchecked(binding).deserialize(input);\r
+ \r
+ result.content = new Variant(binding, value);\r
+ return handler.process(result);\r
+ }\r
+ \r
+ /**\r
+ * Reads a data container including the content data.\r
+ * @throws IOException \r
+ */\r
+ public static DataContainer readFile(File input) throws IOException {\r
+ BinaryFile rf = new BinaryFile( input, "r" );\r
+ try {\r
+ return readFile(rf);\r
+ } finally {\r
+ rf.close();\r
+ } \r
+ }\r
+ \r
+ /**\r
+ * Process a data container using a format handler matching the format and version\r
+ * of the file. \r
+ * @param handlers Map of handlers. Keys are strings of form "format:version".\r
+ */\r
+ public static <T> T readFile(File input, Map<String, FormatHandler<T>> handlers) throws Exception {\r
+ BinaryFile rf = new BinaryFile( input, "r" );\r
+ try {\r
+ return readFile(rf, handlers);\r
+ } finally {\r
+ rf.close();\r
+ } \r
+ }\r
+ \r
+ /**\r
+ * Writes header fields of a container to the given output. Content field is\r
+ * ignored.\r
+ * @throws IOException \r
+ */\r
+ public static void writeHeader(DataOutput output, DataContainer container) throws IOException {\r
+ STRING_SERIALIZER.serialize(output, container.format);\r
+ INTEGER_SERIALIZER.serialize(output, container.version);\r
+ METADATA_SERIALIZER.serialize(output, container.metadata);\r
+ }\r
+ \r
+ /**\r
+ * Writes a data container to the given output.\r
+ * @throws IOException \r
+ */\r
+ public static void writeFile(DataOutput output, DataContainer container) throws IOException {\r
+ writeHeader(output, container);\r
+ VARIANT_SERIALIZER.serialize(output, container.content);\r
+ }\r
+ \r
+ /**\r
+ * Writes a data container to the given file\r
+ * @throws IOException \r
+ */\r
+ public static void writeFile(File output, DataContainer container) throws IOException {\r
+ BinaryFile wf = new BinaryFile( output);\r
+ try {\r
+ writeFile(wf, container);\r
+ } finally {\r
+ wf.close();\r
+ } \r
+ }\r
+ \r
+ public static byte[] writeFile(DataContainer container) throws IOException {\r
+ return DATA_CONTAINER_SERIALIZER.serialize(container);\r
+ }\r
+}\r
Code Review / simantics / platform.git / blobdiff