-package be.nikiroo.utils.serial;
-
-import java.io.ByteArrayInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.NotSerializableException;
-import java.io.OutputStream;
-import java.io.UnsupportedEncodingException;
-import java.lang.reflect.Array;
-import java.lang.reflect.Constructor;
-import java.lang.reflect.Field;
-import java.lang.reflect.Modifier;
-import java.net.URL;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.UnknownFormatConversionException;
-
-import be.nikiroo.utils.IOUtils;
-import be.nikiroo.utils.Image;
-import be.nikiroo.utils.StringUtils;
-import be.nikiroo.utils.streams.Base64InputStream;
-import be.nikiroo.utils.streams.Base64OutputStream;
-import be.nikiroo.utils.streams.NextableInputStream;
-import be.nikiroo.utils.streams.NextableInputStreamStep;
-
-/**
- * Small class to help with serialisation.
- * <p>
- * Note that we do not support inner classes (but we do support nested classes)
- * and all objects require an empty constructor to be deserialised.
- * <p>
- * It is possible to add support to custom types (both the encoder and the
- * decoder will require the custom classes) -- see {@link CustomSerializer}.
- * <p>
- * Default supported types are:
- * <ul>
- * <li>NULL (as a null value)</li>
- * <li>String</li>
- * <li>Boolean</li>
- * <li>Byte</li>
- * <li>Character</li>
- * <li>Short</li>
- * <li>Long</li>
- * <li>Float</li>
- * <li>Double</li>
- * <li>Integer</li>
- * <li>Enum (any enum whose name and value is known by the caller)</li>
- * <li>java.awt.image.BufferedImage (as a {@link CustomSerializer})</li>
- * <li>An array of the above (as a {@link CustomSerializer})</li>
- * <li>URL</li>
- * </ul>
- *
- * @author niki
- */
-public class SerialUtils {
- private static Map<String, CustomSerializer> customTypes;
-
- static {
- customTypes = new HashMap<String, CustomSerializer>();
-
- // Array types:
- customTypes.put("[]", new CustomSerializer() {
- @Override
- protected void toStream(OutputStream out, Object value)
- throws IOException {
-
- // TODO: we use \n to separate, and b64 to un-\n
- // -- but we could use \\n ?
- String type = value.getClass().getCanonicalName();
- type = type.substring(0, type.length() - 2); // remove the []
-
- write(out, type);
- try {
- for (int i = 0; true; i++) {
- Object item = Array.get(value, i);
-
- // encode it normally if direct value
- write(out, "\r");
- if (!SerialUtils.encode(out, item)) {
- try {
- // TODO: bad escaping?
- write(out, "B64:");
- OutputStream out64 = new Base64OutputStream(
- out, true);
- new Exporter(out64).append(item);
- } catch (NotSerializableException e) {
- throw new UnknownFormatConversionException(e
- .getMessage());
- }
- }
- }
- } catch (ArrayIndexOutOfBoundsException e) {
- // Done.
- }
- }
-
- @Override
- protected Object fromStream(InputStream in) throws IOException {
- NextableInputStream stream = new NextableInputStream(in,
- new NextableInputStreamStep('\r'));
-
- try {
- List<Object> list = new ArrayList<Object>();
- stream.next();
- String type = IOUtils.readSmallStream(stream);
-
- while (stream.next()) {
- Object value = new Importer().read(stream).getValue();
- list.add(value);
- }
-
- Object array = Array.newInstance(
- SerialUtils.getClass(type), list.size());
- for (int i = 0; i < list.size(); i++) {
- Array.set(array, i, list.get(i));
- }
-
- return array;
- } catch (Exception e) {
- if (e instanceof IOException) {
- throw (IOException) e;
- }
- throw new IOException(e.getMessage());
- }
- }
-
- @Override
- protected String getType() {
- return "[]";
- }
- });
-
- // URL:
- customTypes.put("java.net.URL", new CustomSerializer() {
- @Override
- protected void toStream(OutputStream out, Object value)
- throws IOException {
- String val = "";
- if (value != null) {
- val = ((URL) value).toString();
- }
-
- out.write(val.getBytes("UTF-8"));
- }
-
- @Override
- protected Object fromStream(InputStream in) throws IOException {
- String val = IOUtils.readSmallStream(in);
- if (!val.isEmpty()) {
- return new URL(val);
- }
-
- return null;
- }
-
- @Override
- protected String getType() {
- return "java.net.URL";
- }
- });
-
- // Images (this is currently the only supported image type by default)
- customTypes.put("be.nikiroo.utils.Image", new CustomSerializer() {
- @Override
- protected void toStream(OutputStream out, Object value)
- throws IOException {
- Image img = (Image) value;
- OutputStream encoded = new Base64OutputStream(out, true);
- try {
- InputStream in = img.newInputStream();
- try {
- IOUtils.write(in, encoded);
- } finally {
- in.close();
- }
- } finally {
- encoded.flush();
- // Cannot close!
- }
- }
-
- @Override
- protected String getType() {
- return "be.nikiroo.utils.Image";
- }
-
- @Override
- protected Object fromStream(InputStream in) throws IOException {
- try {
- // Cannot close it!
- InputStream decoded = new Base64InputStream(in, false);
- return new Image(decoded);
- } catch (IOException e) {
- throw new UnknownFormatConversionException(e.getMessage());
- }
- }
- });
- }
-
- /**
- * Create an empty object of the given type.
- *
- * @param type
- * the object type (its class name)
- *
- * @return the new object
- *
- * @throws ClassNotFoundException
- * if the class cannot be found
- * @throws NoSuchMethodException
- * if the given class is not compatible with this code
- */
- public static Object createObject(String type)
- throws ClassNotFoundException, NoSuchMethodException {
-
- String desc = null;
- try {
- Class<?> clazz = getClass(type);
- String className = clazz.getName();
- List<Object> args = new ArrayList<Object>();
- List<Class<?>> classes = new ArrayList<Class<?>>();
- Constructor<?> ctor = null;
- if (className.contains("$")) {
- for (String parentName = className.substring(0,
- className.lastIndexOf('$'));; parentName = parentName
- .substring(0, parentName.lastIndexOf('$'))) {
- Object parent = createObject(parentName);
- args.add(parent);
- classes.add(parent.getClass());
-
- if (!parentName.contains("$")) {
- break;
- }
- }
-
- // Better error description in case there is no empty
- // constructor:
- desc = "";
- String end = "";
- for (Class<?> parent = clazz; parent != null
- && !parent.equals(Object.class); parent = parent
- .getSuperclass()) {
- if (!desc.isEmpty()) {
- desc += " [:";
- end += "]";
- }
- desc += parent;
- }
- desc += end;
- //
-
- try {
- ctor = clazz.getDeclaredConstructor(classes
- .toArray(new Class[] {}));
- } catch (NoSuchMethodException nsme) {
- // TODO: it seems we do not always need a parameter for each
- // level, so we currently try "ALL" levels or "FIRST" level
- // only -> we should check the actual rule and use it
- ctor = clazz.getDeclaredConstructor(classes.get(0));
- Object firstParent = args.get(0);
- args.clear();
- args.add(firstParent);
- }
- desc = null;
- } else {
- ctor = clazz.getDeclaredConstructor();
- }
-
- ctor.setAccessible(true);
- return ctor.newInstance(args.toArray());
- } catch (ClassNotFoundException e) {
- throw e;
- } catch (NoSuchMethodException e) {
- if (desc != null) {
- throw new NoSuchMethodException("Empty constructor not found: "
- + desc);
- }
- throw e;
- } catch (Exception e) {
- throw new NoSuchMethodException("Cannot instantiate: " + type);
- }
- }
-
- /**
- * Insert a custom serialiser that will take precedence over the default one
- * or the target class.
- *
- * @param serializer
- * the custom serialiser
- */
- static public void addCustomSerializer(CustomSerializer serializer) {
- customTypes.put(serializer.getType(), serializer);
- }
-
- /**
- * Serialise the given object into this {@link OutputStream}.
- * <p>
- * <b>Important: </b>If the operation fails (with a
- * {@link NotSerializableException}), the {@link StringBuilder} will be
- * corrupted (will contain bad, most probably not importable data).
- *
- * @param out
- * the output {@link OutputStream} to serialise to
- * @param o
- * the object to serialise
- * @param map
- * the map of already serialised objects (if the given object or
- * one of its descendant is already present in it, only an ID
- * will be serialised)
- *
- * @throws NotSerializableException
- * if the object cannot be serialised (in this case, the
- * {@link StringBuilder} can contain bad, most probably not
- * importable data)
- * @throws IOException
- * in case of I/O errors
- */
- static void append(OutputStream out, Object o, Map<Integer, Object> map)
- throws NotSerializableException, IOException {
-
- Field[] fields = new Field[] {};
- String type = "";
- String id = "NULL";
-
- if (o != null) {
- int hash = System.identityHashCode(o);
- fields = o.getClass().getDeclaredFields();
- type = o.getClass().getCanonicalName();
- if (type == null) {
- // Anonymous inner classes support
- type = o.getClass().getName();
- }
- id = Integer.toString(hash);
- if (map.containsKey(hash)) {
- fields = new Field[] {};
- } else {
- map.put(hash, o);
- }
- }
-
- write(out, "{\nREF ");
- write(out, type);
- write(out, "@");
- write(out, id);
- write(out, ":");
-
- if (!encode(out, o)) { // check if direct value
- try {
- for (Field field : fields) {
- field.setAccessible(true);
-
- if (field.getName().startsWith("this$")
- || field.isSynthetic()
- || (field.getModifiers() & Modifier.STATIC) == Modifier.STATIC) {
- // Do not keep this links of nested classes
- // Do not keep synthetic fields
- // Do not keep final fields
- continue;
- }
-
- write(out, "\n");
- write(out, field.getName());
- write(out, ":");
-
- Object value = field.get(o);
-
- if (!encode(out, value)) {
- write(out, "\n");
- append(out, value, map);
- }
- }
- } catch (IllegalArgumentException e) {
- e.printStackTrace(); // should not happen (see
- // setAccessible)
- } catch (IllegalAccessException e) {
- e.printStackTrace(); // should not happen (see
- // setAccessible)
- }
-
- write(out, "\n}");
- }
- }
-
- /**
- * Encode the object into the given {@link OutputStream} if possible and if
- * supported.
- * <p>
- * A supported object in this context means an object we can directly
- * encode, like an Integer or a String. Custom objects and arrays are also
- * considered supported, but <b>compound objects are not supported here</b>.
- * <p>
- * For compound objects, you should use {@link Exporter}.
- *
- * @param out
- * the {@link OutputStream} to append to
- * @param value
- * the object to encode (can be NULL, which will be encoded)
- *
- * @return TRUE if success, FALSE if not (the content of the
- * {@link OutputStream} won't be changed in case of failure)
- *
- * @throws IOException
- * in case of I/O error
- */
- static boolean encode(OutputStream out, Object value) throws IOException {
- if (value == null) {
- write(out, "NULL");
- } else if (value.getClass().getSimpleName().endsWith("[]")) {
- // Simple name does support [] suffix and do not return NULL for
- // inner anonymous classes
- customTypes.get("[]").encode(out, value);
- } else if (customTypes.containsKey(value.getClass().getCanonicalName())) {
- customTypes.get(value.getClass().getCanonicalName())//
- .encode(out, value);
- } else if (value instanceof String) {
- encodeString(out, (String) value);
- } else if (value instanceof Boolean) {
- write(out, value);
- } else if (value instanceof Byte) {
- write(out, value);
- write(out, "b");
- } else if (value instanceof Character) {
- encodeString(out, "" + value);
- write(out, "c");
- } else if (value instanceof Short) {
- write(out, value);
- write(out, "s");
- } else if (value instanceof Integer) {
- write(out, value);
- } else if (value instanceof Long) {
- write(out, value);
- write(out, "L");
- } else if (value instanceof Float) {
- write(out, value);
- write(out, "F");
- } else if (value instanceof Double) {
- write(out, value);
- write(out, "d");
- } else if (value instanceof Enum) {
- String type = value.getClass().getCanonicalName();
- write(out, type);
- write(out, ".");
- write(out, ((Enum<?>) value).name());
- write(out, ";");
- } else {
- return false;
- }
-
- return true;
- }
-
- /**
- * Decode the data into an equivalent supported source object.
- * <p>
- * A supported object in this context means an object we can directly
- * encode, like an Integer or a String. Custom objects and arrays are also
- * considered supported, but <b>compound objects are not supported here</b>.
- * <p>
- * For compound objects, you should use {@link Importer}.
- *
- * @param encodedValue
- * the encoded data, cannot be NULL
- *
- * @return the object (can be NULL for NULL encoded values)
- *
- * @throws IOException
- * if the content cannot be converted
- */
- static Object decode(String encodedValue) throws IOException {
- try {
- String cut = "";
- if (encodedValue.length() > 1) {
- cut = encodedValue.substring(0, encodedValue.length() - 1);
- }
-
- if (CustomSerializer.isCustom(encodedValue)) {
- // custom:TYPE_NAME:"content is String-encoded"
- String type = CustomSerializer.typeOf(encodedValue);
- if (customTypes.containsKey(type)) {
- // TODO: we should start with a stream
- InputStream streamEncodedValue = new ByteArrayInputStream(
- encodedValue.getBytes("UTF-8"));
- try {
- return customTypes.get(type).decode(streamEncodedValue);
- } finally {
- streamEncodedValue.close();
- }
- }
- throw new IOException("Unknown custom type: " + type);
- } else if (encodedValue.equals("NULL")
- || encodedValue.equals("null")) {
- return null;
- } else if (encodedValue.endsWith("\"")) {
- return decodeString(encodedValue);
- } else if (encodedValue.equals("true")) {
- return true;
- } else if (encodedValue.equals("false")) {
- return false;
- } else if (encodedValue.endsWith("b")) {
- return Byte.parseByte(cut);
- } else if (encodedValue.endsWith("c")) {
- return decodeString(cut).charAt(0);
- } else if (encodedValue.endsWith("s")) {
- return Short.parseShort(cut);
- } else if (encodedValue.endsWith("L")) {
- return Long.parseLong(cut);
- } else if (encodedValue.endsWith("F")) {
- return Float.parseFloat(cut);
- } else if (encodedValue.endsWith("d")) {
- return Double.parseDouble(cut);
- } else if (encodedValue.endsWith(";")) {
- return decodeEnum(encodedValue);
- } else {
- return Integer.parseInt(encodedValue);
- }
- } catch (Exception e) {
- if (e instanceof IOException) {
- throw (IOException) e;
- }
- throw new IOException(e.getMessage(), e);
- }
- }
-
- /**
- * Write the given {@link String} into the given {@link OutputStream} in
- * UTF-8.
- *
- * @param out
- * the {@link OutputStream}
- * @param data
- * the data to write, cannot be NULL
- *
- * @throws IOException
- * in case of I/O error
- */
- static void write(OutputStream out, Object data) throws IOException {
- try {
- out.write(data.toString().getBytes("UTF-8"));
- } catch (UnsupportedEncodingException e) {
- // A conforming JVM is required to support UTF-8
- e.printStackTrace();
- }
- }
-
- /**
- * Return the corresponding class or throw an {@link Exception} if it
- * cannot.
- *
- * @param type
- * the class name to look for
- *
- * @return the class (will never be NULL)
- *
- * @throws ClassNotFoundException
- * if the class cannot be found
- * @throws NoSuchMethodException
- * if the class cannot be created (usually because it or its
- * enclosing class doesn't have an empty constructor)
- */
- static private Class<?> getClass(String type)
- throws ClassNotFoundException, NoSuchMethodException {
- Class<?> clazz = null;
- try {
- clazz = Class.forName(type);
- } catch (ClassNotFoundException e) {
- int pos = type.length();
- pos = type.lastIndexOf(".", pos);
- if (pos >= 0) {
- String parentType = type.substring(0, pos);
- String nestedType = type.substring(pos + 1);
- Class<?> javaParent = null;
- try {
- javaParent = getClass(parentType);
- parentType = javaParent.getName();
- clazz = Class.forName(parentType + "$" + nestedType);
- } catch (Exception ee) {
- }
-
- if (javaParent == null) {
- throw new NoSuchMethodException(
- "Class not found: "
- + type
- + " (the enclosing class cannot be created: maybe it doesn't have an empty constructor?)");
- }
- }
- }
-
- if (clazz == null) {
- throw new ClassNotFoundException("Class not found: " + type);
- }
-
- return clazz;
- }
-
- @SuppressWarnings({ "unchecked", "rawtypes" })
- static private Enum<?> decodeEnum(String escaped) {
- // escaped: be.xxx.EnumType.VALUE;
- int pos = escaped.lastIndexOf(".");
- String type = escaped.substring(0, pos);
- String name = escaped.substring(pos + 1, escaped.length() - 1);
-
- try {
- return Enum.valueOf((Class<Enum>) getClass(type), name);
- } catch (Exception e) {
- throw new UnknownFormatConversionException("Unknown enum: <" + type
- + "> " + name);
- }
- }
-
- // aa bb -> "aa\tbb"
- static void encodeString(OutputStream out, String raw) throws IOException {
- // TODO: not. efficient.
- out.write('\"');
- // TODO !! utf-8 required
- for (char car : raw.toCharArray()) {
- encodeString(out, car);
- }
- out.write('\"');
- }
-
- // aa bb -> "aa\tbb"
- static void encodeString(OutputStream out, InputStream raw)
- throws IOException {
- out.write('\"');
- byte buffer[] = new byte[4096];
- for (int len = 0; (len = raw.read(buffer)) > 0;) {
- for (int i = 0; i < len; i++) {
- // TODO: not 100% correct, look up howto for UTF-8
- encodeString(out, (char) buffer[i]);
- }
- }
- out.write('\"');
- }
-
- // for encode string, NOT to encode a char by itself!
- static void encodeString(OutputStream out, char raw) throws IOException {
- switch (raw) {
- case '\\':
- out.write('\\');
- out.write('\\');
- break;
- case '\r':
- out.write('\\');
- out.write('r');
- break;
- case '\n':
- out.write('\\');
- out.write('n');
- break;
- case '"':
- out.write('\\');
- out.write('\"');
- break;
- default:
- out.write(raw);
- break;
- }
- }
-
- // "aa\tbb" -> aa bb
- static String decodeString(String escaped) {
- StringBuilder builder = new StringBuilder();
-
- boolean escaping = false;
- for (char car : escaped.toCharArray()) {
- if (!escaping) {
- if (car == '\\') {
- escaping = true;
- } else {
- builder.append(car);
- }
- } else {
- switch (car) {
- case '\\':
- builder.append('\\');
- break;
- case 'r':
- builder.append('\r');
- break;
- case 'n':
- builder.append('\n');
- break;
- case '"':
- builder.append('"');
- break;
- }
- escaping = false;
- }
- }
-
- return builder.substring(1, builder.length() - 1);
- }
-}