package be.nikiroo.utils.serial;
-import java.lang.reflect.Constructor;
-import java.lang.reflect.Field;
-import java.lang.reflect.InvocationTargetException;
+import java.io.IOException;
import java.io.NotSerializableException;
+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.Image;
/**
- * Small class to help serialise/deserialise objects.
+ * 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
*/
static {
customTypes = new HashMap<String, CustomSerializer>();
- // TODO: add "default" custom serialisers
+
+ // Array types:
+ customTypes.put("[]", new CustomSerializer() {
+ @Override
+ protected String toString(Object value) {
+ String type = value.getClass().getCanonicalName();
+ type = type.substring(0, type.length() - 2); // remove the []
+
+ StringBuilder builder = new StringBuilder();
+ builder.append(type).append("\n");
+ try {
+ for (int i = 0; true; i++) {
+ Object item = Array.get(value, i);
+ // encode it normally if direct value
+ if (!SerialUtils.encode(builder, item)) {
+ try {
+ // use ZIP: if not
+ new Exporter().append(item).appendTo(builder,
+ true, false);
+ } catch (NotSerializableException e) {
+ throw new UnknownFormatConversionException(e
+ .getMessage());
+ }
+ }
+ builder.append("\n");
+ }
+ } catch (ArrayIndexOutOfBoundsException e) {
+ // Done.
+ }
+
+ return builder.toString();
+ }
+
+ @Override
+ protected String getType() {
+ return "[]";
+ }
+
+ @Override
+ protected Object fromString(String content) throws IOException {
+ String[] tab = content.split("\n");
+
+ try {
+ Object array = Array.newInstance(
+ SerialUtils.getClass(tab[0]), tab.length - 1);
+ for (int i = 1; i < tab.length; i++) {
+ Object value = new Importer().read(tab[i]).getValue();
+ Array.set(array, i - 1, value);
+ }
+
+ return array;
+ } catch (Exception e) {
+ if (e instanceof IOException) {
+ throw (IOException) e;
+ }
+ throw new IOException(e.getMessage());
+ }
+ }
+ });
+
+ // URL:
+ customTypes.put("java.net.URL", new CustomSerializer() {
+ @Override
+ protected String toString(Object value) {
+ if (value != null) {
+ return ((URL) value).toString();
+ }
+ return null;
+ }
+
+ @Override
+ protected Object fromString(String content) throws IOException {
+ if (content != null) {
+ return new URL(content);
+ }
+ 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 String toString(Object value) {
+ return ((Image) value).toBase64();
+ }
+
+ @Override
+ protected String getType() {
+ return "be.nikiroo.utils.Image";
+ }
+
+ @Override
+ protected Object fromString(String content) {
+ try {
+ return new Image(content);
+ } catch (IOException e) {
+ throw new UnknownFormatConversionException(e.getMessage());
+ }
+ }
+ });
}
-
+
/**
* Create an empty object of the given type.
*
*
* @return the new object
*
- * @throws NoSuchMethodException if the given class is not compatible with this code
- * @throws ClassNotFoundException if the class cannot be found or created
+ * @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 NoSuchMethodException,
- ClassNotFoundException {
+ public static Object createObject(String type)
+ throws ClassNotFoundException, NoSuchMethodException {
+ String desc = null;
try {
Class<?> clazz = getClass(type);
- if (clazz == null) {
- throw new ClassNotFoundException("Class not found: " + type);
- }
-
String className = clazz.getName();
- Object[] args = null;
+ List<Object> args = new ArrayList<Object>();
+ List<Class<?>> classes = new ArrayList<Class<?>>();
Constructor<?> ctor = null;
if (className.contains("$")) {
- Object javaParent = createObject(className.substring(0,
- className.lastIndexOf('$')));
- args = new Object[] { javaParent };
- ctor = clazz.getDeclaredConstructor(new Class[] { javaParent
- .getClass() });
+ 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 e 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 {
- args = new Object[] {};
ctor = clazz.getDeclaredConstructor();
}
ctor.setAccessible(true);
- return ctor.newInstance(args);
+ return ctor.newInstance(args.toArray());
+ } catch (ClassNotFoundException e) {
+ throw e;
} catch (NoSuchMethodException e) {
- throw new NoSuchMethodException(
- String.format(
- "Objects of type \"%s\" cannot be created by this code: maybe the class"
- + " or its enclosing class doesn't have an empty constructor?",
- type));
-
+ if (desc != null) {
+ throw new NoSuchMethodException("Empty constructor not found: "
+ + desc);
+ }
+ throw e;
+ } catch (Exception e) {
+ throw new NoSuchMethodException("Cannot instantiate: " + type);
}
- catch (SecurityException e) { throw new ClassNotFoundException("Cannot instantiate: " + type, e); }
- catch (InstantiationException e) { throw new ClassNotFoundException("Cannot instantiate: " + type, e); }
- catch (IllegalAccessException e) { throw new ClassNotFoundException("Cannot instantiate: " + type, e); }
- catch (IllegalArgumentException e) { throw new ClassNotFoundException("Cannot instantiate: " + type, e); }
- catch (InvocationTargetException e) { throw new ClassNotFoundException("Cannot instantiate: " + type, e); }
}
+ /**
+ * 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 StringBuilder}.
+ * <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 builder
+ * the output {@link StringBuilder} 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)
+ */
static void append(StringBuilder builder, Object o, Map<Integer, Object> map)
throws NotSerializableException {
fields = o.getClass().getDeclaredFields();
type = o.getClass().getCanonicalName();
if (type == null) {
- throw new NotSerializableException(
- String.format(
- "Cannot find the class for this object: %s (it could be an inner class, which is not supported)",
- o));
+ // Anonymous inner classes support
+ type = o.getClass().getName();
}
id = Integer.toString(hash);
if (map.containsKey(hash)) {
}
}
- builder.append("{\nREF ").append(type).append("@").append(id);
- try {
- for (Field field : fields) {
- field.setAccessible(true);
+ builder.append("{\nREF ").append(type).append("@").append(id)
+ .append(":");
+ if (!encode(builder, o)) { // check if direct value
+ try {
+ for (Field field : fields) {
+ field.setAccessible(true);
- if (field.getName().startsWith("this$")) {
- // Do not keep this links of nested classes
- continue;
- }
+ 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;
+ }
- builder.append("\n");
- builder.append(field.getName());
- builder.append(":");
- Object value;
+ builder.append("\n");
+ builder.append(field.getName());
+ builder.append(":");
+ Object value;
- value = field.get(o);
+ value = field.get(o);
- if (!encode(builder, value)) {
- builder.append("\n");
- append(builder, value, map);
+ if (!encode(builder, value)) {
+ builder.append("\n");
+ append(builder, value, map);
+ }
}
+ } catch (IllegalArgumentException e) {
+ e.printStackTrace(); // should not happen (see
+ // setAccessible)
+ } catch (IllegalAccessException e) {
+ e.printStackTrace(); // should not happen (see
+ // setAccessible)
}
- } catch (IllegalArgumentException e) {
- e.printStackTrace(); // should not happen (see setAccessible)
- } catch (IllegalAccessException e) {
- e.printStackTrace(); // should not happen (see setAccessible)
}
builder.append("\n}");
}
- // return true if encoded (supported)
+ /**
+ * Encode the object into the given builder 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 builder
+ * the builder 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 builder won't
+ * be changed in case of failure)
+ */
static boolean encode(StringBuilder builder, Object value) {
if (value == null) {
builder.append("NULL");
+ } else if (value.getClass().getSimpleName().endsWith("[]")) {
+ // Simple name does support [] suffix and do not return NULL for
+ // inner anonymous classes
+ return customTypes.get("[]").encode(builder, value);
} else if (customTypes.containsKey(value.getClass().getCanonicalName())) {
- customTypes.get(value.getClass().getCanonicalName())//
+ return customTypes.get(value.getClass().getCanonicalName())//
.encode(builder, value);
} else if (value instanceof String) {
encodeString(builder, (String) value);
} else if (value instanceof Byte) {
builder.append(value).append('b');
} else if (value instanceof Character) {
- encodeString(builder, (String) value);
+ encodeString(builder, "" + value);
builder.append('c');
} else if (value instanceof Short) {
builder.append(value).append('s');
builder.append(value).append('F');
} else if (value instanceof Double) {
builder.append(value).append('d');
+ } else if (value instanceof Enum) {
+ String type = value.getClass().getCanonicalName();
+ builder.append(type).append(".").append(((Enum<?>) value).name())
+ .append(";");
} else {
return false;
}
return true;
}
- static Object decode(String encodedValue) {
- String cut = "";
- if (encodedValue.length() > 1) {
- cut = encodedValue.substring(0, encodedValue.length() - 1);
- }
+ /**
+ * 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)) {
- return customTypes.get(type).decode(encodedValue);
+ if (CustomSerializer.isCustom(encodedValue)) {
+ // custom:TYPE_NAME:"content is String-encoded"
+ String type = CustomSerializer.typeOf(encodedValue);
+ if (customTypes.containsKey(type)) {
+ return customTypes.get(type).decode(encodedValue);
+ }
+ 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 {
- throw new java.util.UnknownFormatConversionException(
- "Unknown custom type: " + type);
+ return Integer.parseInt(encodedValue);
}
- } 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 {
- return Integer.parseInt(encodedValue);
+ } catch (Exception e) {
+ if (e instanceof IOException) {
+ throw (IOException) e;
+ }
+ throw new IOException(e.getMessage());
}
}
-
- static private Class<?> getClass(String type) throws ClassNotFoundException,
- NoSuchMethodException {
+
+ /**
+ * 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);
}
}
+ if (clazz == null) {
+ throw new ClassNotFoundException("Class not found: " + type);
+ }
+
return clazz;
}
-
+
+ @SuppressWarnings({ "unchecked", "rawtypes" })
+ private static 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"
private static void encodeString(StringBuilder builder, String raw) {
builder.append('\"');
}
}
- return builder.substring(1, builder.length() - 1).toString();
+ return builder.substring(1, builder.length() - 1);
}
}