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Diffstat (limited to 'extras/src/main/java/com')
7 files changed, 1031 insertions, 0 deletions
diff --git a/extras/src/main/java/com/google/gson/extras/examples/rawcollections/RawCollectionsExample.java b/extras/src/main/java/com/google/gson/extras/examples/rawcollections/RawCollectionsExample.java new file mode 100644 index 00000000..bd7c2d24 --- /dev/null +++ b/extras/src/main/java/com/google/gson/extras/examples/rawcollections/RawCollectionsExample.java @@ -0,0 +1,55 @@ +/* + * Copyright (C) 2011 Google Inc. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package com.google.gson.extras.examples.rawcollections; + +import java.util.ArrayList; +import java.util.Collection; + +import com.google.gson.Gson; +import com.google.gson.JsonArray; +import com.google.gson.JsonParser; + +public class RawCollectionsExample { + static class Event { + private String name; + private String source; + private Event(String name, String source) { + this.name = name; + this.source = source; + } + @Override + public String toString() { + return String.format("(name=%s, source=%s)", name, source); + } + } + + @SuppressWarnings({ "unchecked", "rawtypes" }) + public static void main(String[] args) { + Gson gson = new Gson(); + Collection collection = new ArrayList(); + collection.add("hello"); + collection.add(5); + collection.add(new Event("GREETINGS", "guest")); + String json = gson.toJson(collection); + System.out.println("Using Gson.toJson() on a raw collection: " + json); + JsonParser parser = new JsonParser(); + JsonArray array = parser.parse(json).getAsJsonArray(); + String message = gson.fromJson(array.get(0), String.class); + int number = gson.fromJson(array.get(1), int.class); + Event event = gson.fromJson(array.get(2), Event.class); + System.out.printf("Using Gson.fromJson() to get: %s, %d, %s", message, number, event); + } +} diff --git a/extras/src/main/java/com/google/gson/graph/GraphAdapterBuilder.java b/extras/src/main/java/com/google/gson/graph/GraphAdapterBuilder.java new file mode 100644 index 00000000..cd8ea00f --- /dev/null +++ b/extras/src/main/java/com/google/gson/graph/GraphAdapterBuilder.java @@ -0,0 +1,308 @@ +/* + * Copyright (C) 2011 Google Inc. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package com.google.gson.graph; + +import com.google.gson.Gson; +import com.google.gson.GsonBuilder; +import com.google.gson.InstanceCreator; +import com.google.gson.JsonElement; +import com.google.gson.TypeAdapter; +import com.google.gson.TypeAdapterFactory; +import com.google.gson.internal.ConstructorConstructor; +import com.google.gson.internal.ObjectConstructor; +import com.google.gson.reflect.TypeToken; +import com.google.gson.stream.JsonReader; +import com.google.gson.stream.JsonToken; +import com.google.gson.stream.JsonWriter; +import java.io.IOException; +import java.lang.reflect.Type; +import java.util.HashMap; +import java.util.IdentityHashMap; +import java.util.LinkedList; +import java.util.Map; +import java.util.Queue; + +/** + * Writes a graph of objects as a list of named nodes. + */ +// TODO: proper documentation +@SuppressWarnings("rawtypes") +public final class GraphAdapterBuilder { + private final Map<Type, InstanceCreator<?>> instanceCreators; + private final ConstructorConstructor constructorConstructor; + + public GraphAdapterBuilder() { + this.instanceCreators = new HashMap<Type, InstanceCreator<?>>(); + this.constructorConstructor = new ConstructorConstructor(instanceCreators); + } + public GraphAdapterBuilder addType(Type type) { + final ObjectConstructor<?> objectConstructor = constructorConstructor.get(TypeToken.get(type)); + InstanceCreator<Object> instanceCreator = new InstanceCreator<Object>() { + public Object createInstance(Type type) { + return objectConstructor.construct(); + } + }; + return addType(type, instanceCreator); + } + + public GraphAdapterBuilder addType(Type type, InstanceCreator<?> instanceCreator) { + if (type == null || instanceCreator == null) { + throw new NullPointerException(); + } + instanceCreators.put(type, instanceCreator); + return this; + } + + public void registerOn(GsonBuilder gsonBuilder) { + Factory factory = new Factory(instanceCreators); + gsonBuilder.registerTypeAdapterFactory(factory); + for (Map.Entry<Type, InstanceCreator<?>> entry : instanceCreators.entrySet()) { + gsonBuilder.registerTypeAdapter(entry.getKey(), factory); + } + } + + static class Factory implements TypeAdapterFactory, InstanceCreator { + private final Map<Type, InstanceCreator<?>> instanceCreators; + private final ThreadLocal<Graph> graphThreadLocal = new ThreadLocal<Graph>(); + + Factory(Map<Type, InstanceCreator<?>> instanceCreators) { + this.instanceCreators = instanceCreators; + } + + public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) { + if (!instanceCreators.containsKey(type.getType())) { + return null; + } + + final TypeAdapter<T> typeAdapter = gson.getDelegateAdapter(this, type); + final TypeAdapter<JsonElement> elementAdapter = gson.getAdapter(JsonElement.class); + return new TypeAdapter<T>() { + @Override public void write(JsonWriter out, T value) throws IOException { + if (value == null) { + out.nullValue(); + return; + } + + Graph graph = graphThreadLocal.get(); + boolean writeEntireGraph = false; + + /* + * We have one of two cases: + * 1. We've encountered the first known object in this graph. Write + * out the graph, starting with that object. + * 2. We've encountered another graph object in the course of #1. + * Just write out this object's name. We'll circle back to writing + * out the object's value as a part of #1. + */ + + if (graph == null) { + writeEntireGraph = true; + graph = new Graph(new IdentityHashMap<Object, Element<?>>()); + } + + @SuppressWarnings("unchecked") // graph.map guarantees consistency between value and T + Element<T> element = (Element<T>) graph.map.get(value); + if (element == null) { + element = new Element<T>(value, graph.nextName(), typeAdapter, null); + graph.map.put(value, element); + graph.queue.add(element); + } + + if (writeEntireGraph) { + graphThreadLocal.set(graph); + try { + out.beginObject(); + Element<?> current; + while ((current = graph.queue.poll()) != null) { + out.name(current.id); + current.write(out); + } + out.endObject(); + } finally { + graphThreadLocal.remove(); + } + } else { + out.value(element.id); + } + } + + @Override public T read(JsonReader in) throws IOException { + if (in.peek() == JsonToken.NULL) { + in.nextNull(); + return null; + } + + /* + * Again we have one of two cases: + * 1. We've encountered the first known object in this graph. Read + * the entire graph in as a map from names to their JsonElements. + * Then convert the first JsonElement to its Java object. + * 2. We've encountered another graph object in the course of #1. + * Read in its name, then deserialize its value from the + * JsonElement in our map. We need to do this lazily because we + * don't know which TypeAdapter to use until a value is + * encountered in the wild. + */ + + String currentName = null; + Graph graph = graphThreadLocal.get(); + boolean readEntireGraph = false; + + if (graph == null) { + graph = new Graph(new HashMap<Object, Element<?>>()); + readEntireGraph = true; + + // read the entire tree into memory + in.beginObject(); + while (in.hasNext()) { + String name = in.nextName(); + if (currentName == null) { + currentName = name; + } + JsonElement element = elementAdapter.read(in); + graph.map.put(name, new Element<T>(null, name, typeAdapter, element)); + } + in.endObject(); + } else { + currentName = in.nextString(); + } + + if (readEntireGraph) { + graphThreadLocal.set(graph); + } + try { + @SuppressWarnings("unchecked") // graph.map guarantees consistency between value and T + Element<T> element = (Element<T>) graph.map.get(currentName); + // now that we know the typeAdapter for this name, go from JsonElement to 'T' + if (element.value == null) { + element.typeAdapter = typeAdapter; + element.read(graph); + } + return element.value; + } finally { + if (readEntireGraph) { + graphThreadLocal.remove(); + } + } + } + }; + } + + /** + * Hook for the graph adapter to get a reference to a deserialized value + * before that value is fully populated. This is useful to deserialize + * values that directly or indirectly reference themselves: we can hand + * out an instance before read() returns. + * + * <p>Gson should only ever call this method when we're expecting it to; + * that is only when we've called back into Gson to deserialize a tree. + */ + @SuppressWarnings("unchecked") + public Object createInstance(Type type) { + Graph graph = graphThreadLocal.get(); + if (graph == null || graph.nextCreate == null) { + throw new IllegalStateException("Unexpected call to createInstance() for " + type); + } + InstanceCreator<?> creator = instanceCreators.get(type); + Object result = creator.createInstance(type); + graph.nextCreate.value = result; + graph.nextCreate = null; + return result; + } + } + + static class Graph { + /** + * The graph elements. On serialization keys are objects (using an identity + * hash map) and on deserialization keys are the string names (using a + * standard hash map). + */ + private final Map<Object, Element<?>> map; + + /** + * The queue of elements to write during serialization. Unused during + * deserialization. + */ + private final Queue<Element> queue = new LinkedList<Element>(); + + /** + * The instance currently being deserialized. Used as a backdoor between + * the graph traversal (which needs to know instances) and instance creators + * which create them. + */ + private Element nextCreate; + + private Graph(Map<Object, Element<?>> map) { + this.map = map; + } + + /** + * Returns a unique name for an element to be inserted into the graph. + */ + public String nextName() { + return "0x" + Integer.toHexString(map.size() + 1); + } + } + + /** + * An element of the graph during serialization or deserialization. + */ + static class Element<T> { + /** + * This element's name in the top level graph object. + */ + private final String id; + + /** + * The value if known. During deserialization this is lazily populated. + */ + private T value; + + /** + * This element's type adapter if known. During deserialization this is + * lazily populated. + */ + private TypeAdapter<T> typeAdapter; + + /** + * The element to deserialize. Unused in serialization. + */ + private final JsonElement element; + + Element(T value, String id, TypeAdapter<T> typeAdapter, JsonElement element) { + this.value = value; + this.id = id; + this.typeAdapter = typeAdapter; + this.element = element; + } + + void write(JsonWriter out) throws IOException { + typeAdapter.write(out, value); + } + + void read(Graph graph) throws IOException { + if (graph.nextCreate != null) { + throw new IllegalStateException("Unexpected recursive call to read() for " + id); + } + graph.nextCreate = this; + value = typeAdapter.fromJsonTree(element); + if (value == null) { + throw new IllegalStateException("non-null value deserialized to null: " + element); + } + } + } +} diff --git a/extras/src/main/java/com/google/gson/interceptors/Intercept.java b/extras/src/main/java/com/google/gson/interceptors/Intercept.java new file mode 100644 index 00000000..0c4e9043 --- /dev/null +++ b/extras/src/main/java/com/google/gson/interceptors/Intercept.java @@ -0,0 +1,64 @@ +/* + * Copyright (C) 2012 Google Inc. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package com.google.gson.interceptors; + +import java.lang.annotation.ElementType; +import java.lang.annotation.Retention; +import java.lang.annotation.RetentionPolicy; +import java.lang.annotation.Target; + + +/** + * Use this annotation to indicate various interceptors for class instances after + * they have been processed by Gson. For example, you can use it to validate an instance + * after it has been deserialized from Json. + * Here is an example of how this annotation is used: + * <p>Here is an example of how this annotation is used: + * <p><pre> + * @Intercept(postDeserialize=UserValidator.class) + * public class User { + * String name; + * String password; + * String emailAddress; + * } + * + * public class UserValidator implements JsonPostDeserializer<User> { + * public void postDeserialize(User user) { + * // Do some checks on user + * if (user.name == null || user.password == null) { + * throw new JsonParseException("name and password are required fields."); + * } + * if (user.emailAddress == null) { + * emailAddress = "unknown"; // assign a default value. + * } + * } + * } + * </pre></p> + * + * @author Inderjeet Singh + */ +@Retention(RetentionPolicy.RUNTIME) +@Target(ElementType.TYPE) +public @interface Intercept { + + /** + * Specify the class that provides the methods that should be invoked after an instance + * has been deserialized. + */ + @SuppressWarnings("rawtypes") + public Class<? extends JsonPostDeserializer> postDeserialize(); +} diff --git a/extras/src/main/java/com/google/gson/interceptors/InterceptorFactory.java b/extras/src/main/java/com/google/gson/interceptors/InterceptorFactory.java new file mode 100644 index 00000000..907fca3a --- /dev/null +++ b/extras/src/main/java/com/google/gson/interceptors/InterceptorFactory.java @@ -0,0 +1,49 @@ +package com.google.gson.interceptors; + +import com.google.gson.Gson; +import com.google.gson.TypeAdapter; +import com.google.gson.TypeAdapterFactory; +import com.google.gson.reflect.TypeToken; +import com.google.gson.stream.JsonReader; +import com.google.gson.stream.JsonWriter; +import java.io.IOException; + +/** + * A type adapter factory that implements {@code @Intercept}. + */ +public final class InterceptorFactory implements TypeAdapterFactory { + public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) { + Intercept intercept = type.getRawType().getAnnotation(Intercept.class); + if (intercept == null) { + return null; + } + + TypeAdapter<T> delegate = gson.getDelegateAdapter(this, type); + return new InterceptorAdapter<T>(delegate, intercept); + } + + static class InterceptorAdapter<T> extends TypeAdapter<T> { + private final TypeAdapter<T> delegate; + private final JsonPostDeserializer<T> postDeserializer; + + @SuppressWarnings("unchecked") // ? + public InterceptorAdapter(TypeAdapter<T> delegate, Intercept intercept) { + try { + this.delegate = delegate; + this.postDeserializer = intercept.postDeserialize().newInstance(); + } catch (Exception e) { + throw new RuntimeException(e); + } + } + + @Override public void write(JsonWriter out, T value) throws IOException { + delegate.write(out, value); + } + + @Override public T read(JsonReader in) throws IOException { + T result = delegate.read(in); + postDeserializer.postDeserialize(result); + return result; + } + } +} diff --git a/extras/src/main/java/com/google/gson/interceptors/JsonPostDeserializer.java b/extras/src/main/java/com/google/gson/interceptors/JsonPostDeserializer.java new file mode 100644 index 00000000..0f3a72ca --- /dev/null +++ b/extras/src/main/java/com/google/gson/interceptors/JsonPostDeserializer.java @@ -0,0 +1,33 @@ +/* + * Copyright (C) 2012 Google Inc. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package com.google.gson.interceptors; + +import com.google.gson.InstanceCreator; + +/** + * This interface is implemented by a class that wishes to inspect or modify an object + * after it has been deserialized. You must define a no-args constructor or register an + * {@link InstanceCreator} for such a class. + * + * @author Inderjeet Singh + */ +public interface JsonPostDeserializer<T> { + + /** + * This method is called by Gson after the object has been deserialized from Json. + */ + public void postDeserialize(T object); +} diff --git a/extras/src/main/java/com/google/gson/typeadapters/RuntimeTypeAdapterFactory.java b/extras/src/main/java/com/google/gson/typeadapters/RuntimeTypeAdapterFactory.java new file mode 100644 index 00000000..5bdf6e51 --- /dev/null +++ b/extras/src/main/java/com/google/gson/typeadapters/RuntimeTypeAdapterFactory.java @@ -0,0 +1,240 @@ +/* + * Copyright (C) 2011 Google Inc. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package com.google.gson.typeadapters; + +import java.io.IOException; +import java.util.LinkedHashMap; +import java.util.Map; + +import com.google.gson.Gson; +import com.google.gson.JsonElement; +import com.google.gson.JsonObject; +import com.google.gson.JsonParseException; +import com.google.gson.JsonPrimitive; +import com.google.gson.TypeAdapter; +import com.google.gson.TypeAdapterFactory; +import com.google.gson.internal.Streams; +import com.google.gson.reflect.TypeToken; +import com.google.gson.stream.JsonReader; +import com.google.gson.stream.JsonWriter; + +/** + * Adapts values whose runtime type may differ from their declaration type. This + * is necessary when a field's type is not the same type that GSON should create + * when deserializing that field. For example, consider these types: + * <pre> {@code + * abstract class Shape { + * int x; + * int y; + * } + * class Circle extends Shape { + * int radius; + * } + * class Rectangle extends Shape { + * int width; + * int height; + * } + * class Diamond extends Shape { + * int width; + * int height; + * } + * class Drawing { + * Shape bottomShape; + * Shape topShape; + * } + * }</pre> + * <p>Without additional type information, the serialized JSON is ambiguous. Is + * the bottom shape in this drawing a rectangle or a diamond? <pre> {@code + * { + * "bottomShape": { + * "width": 10, + * "height": 5, + * "x": 0, + * "y": 0 + * }, + * "topShape": { + * "radius": 2, + * "x": 4, + * "y": 1 + * } + * }}</pre> + * This class addresses this problem by adding type information to the + * serialized JSON and honoring that type information when the JSON is + * deserialized: <pre> {@code + * { + * "bottomShape": { + * "type": "Diamond", + * "width": 10, + * "height": 5, + * "x": 0, + * "y": 0 + * }, + * "topShape": { + * "type": "Circle", + * "radius": 2, + * "x": 4, + * "y": 1 + * } + * }}</pre> + * Both the type field name ({@code "type"}) and the type labels ({@code + * "Rectangle"}) are configurable. + * + * <h3>Registering Types</h3> + * Create a {@code RuntimeTypeAdapter} by passing the base type and type field + * name to the {@link #of} factory method. If you don't supply an explicit type + * field name, {@code "type"} will be used. <pre> {@code + * RuntimeTypeAdapter<Shape> shapeAdapter + * = RuntimeTypeAdapter.of(Shape.class, "type"); + * }</pre> + * Next register all of your subtypes. Every subtype must be explicitly + * registered. This protects your application from injection attacks. If you + * don't supply an explicit type label, the type's simple name will be used. + * <pre> {@code + * shapeAdapter.registerSubtype(Rectangle.class, "Rectangle"); + * shapeAdapter.registerSubtype(Circle.class, "Circle"); + * shapeAdapter.registerSubtype(Diamond.class, "Diamond"); + * }</pre> + * Finally, register the type adapter in your application's GSON builder: + * <pre> {@code + * Gson gson = new GsonBuilder() + * .registerTypeAdapter(Shape.class, shapeAdapter) + * .create(); + * }</pre> + * Like {@code GsonBuilder}, this API supports chaining: <pre> {@code + * RuntimeTypeAdapter<Shape> shapeAdapter = RuntimeTypeAdapterFactory.of(Shape.class) + * .registerSubtype(Rectangle.class) + * .registerSubtype(Circle.class) + * .registerSubtype(Diamond.class); + * }</pre> + */ +public final class RuntimeTypeAdapterFactory<T> implements TypeAdapterFactory { + private final Class<?> baseType; + private final String typeFieldName; + private final Map<String, Class<?>> labelToSubtype = new LinkedHashMap<String, Class<?>>(); + private final Map<Class<?>, String> subtypeToLabel = new LinkedHashMap<Class<?>, String>(); + + private RuntimeTypeAdapterFactory(Class<?> baseType, String typeFieldName) { + if (typeFieldName == null || baseType == null) { + throw new NullPointerException(); + } + this.baseType = baseType; + this.typeFieldName = typeFieldName; + } + + /** + * Creates a new runtime type adapter using for {@code baseType} using {@code + * typeFieldName} as the type field name. Type field names are case sensitive. + */ + public static <T> RuntimeTypeAdapterFactory<T> of(Class<T> baseType, String typeFieldName) { + return new RuntimeTypeAdapterFactory<T>(baseType, typeFieldName); + } + + /** + * Creates a new runtime type adapter for {@code baseType} using {@code "type"} as + * the type field name. + */ + public static <T> RuntimeTypeAdapterFactory<T> of(Class<T> baseType) { + return new RuntimeTypeAdapterFactory<T>(baseType, "type"); + } + + /** + * Registers {@code type} identified by {@code label}. Labels are case + * sensitive. + * + * @throws IllegalArgumentException if either {@code type} or {@code label} + * have already been registered on this type adapter. + */ + public RuntimeTypeAdapterFactory<T> registerSubtype(Class<? extends T> type, String label) { + if (type == null || label == null) { + throw new NullPointerException(); + } + if (subtypeToLabel.containsKey(type) || labelToSubtype.containsKey(label)) { + throw new IllegalArgumentException("types and labels must be unique"); + } + labelToSubtype.put(label, type); + subtypeToLabel.put(type, label); + return this; + } + + /** + * Registers {@code type} identified by its {@link Class#getSimpleName simple + * name}. Labels are case sensitive. + * + * @throws IllegalArgumentException if either {@code type} or its simple name + * have already been registered on this type adapter. + */ + public RuntimeTypeAdapterFactory<T> registerSubtype(Class<? extends T> type) { + return registerSubtype(type, type.getSimpleName()); + } + + public <R> TypeAdapter<R> create(Gson gson, TypeToken<R> type) { + if (type.getRawType() != baseType) { + return null; + } + + final Map<String, TypeAdapter<?>> labelToDelegate + = new LinkedHashMap<String, TypeAdapter<?>>(); + final Map<Class<?>, TypeAdapter<?>> subtypeToDelegate + = new LinkedHashMap<Class<?>, TypeAdapter<?>>(); + for (Map.Entry<String, Class<?>> entry : labelToSubtype.entrySet()) { + TypeAdapter<?> delegate = gson.getDelegateAdapter(this, TypeToken.get(entry.getValue())); + labelToDelegate.put(entry.getKey(), delegate); + subtypeToDelegate.put(entry.getValue(), delegate); + } + + return new TypeAdapter<R>() { + @Override public R read(JsonReader in) throws IOException { + JsonElement jsonElement = Streams.parse(in); + JsonElement labelJsonElement = jsonElement.getAsJsonObject().remove(typeFieldName); + if (labelJsonElement == null) { + throw new JsonParseException("cannot deserialize " + baseType + + " because it does not define a field named " + typeFieldName); + } + String label = labelJsonElement.getAsString(); + @SuppressWarnings("unchecked") // registration requires that subtype extends T + TypeAdapter<R> delegate = (TypeAdapter<R>) labelToDelegate.get(label); + if (delegate == null) { + throw new JsonParseException("cannot deserialize " + baseType + " subtype named " + + label + "; did you forget to register a subtype?"); + } + return delegate.fromJsonTree(jsonElement); + } + + @Override public void write(JsonWriter out, R value) throws IOException { + Class<?> srcType = value.getClass(); + String label = subtypeToLabel.get(srcType); + @SuppressWarnings("unchecked") // registration requires that subtype extends T + TypeAdapter<R> delegate = (TypeAdapter<R>) subtypeToDelegate.get(srcType); + if (delegate == null) { + throw new JsonParseException("cannot serialize " + srcType.getName() + + "; did you forget to register a subtype?"); + } + JsonObject jsonObject = delegate.toJsonTree(value).getAsJsonObject(); + if (jsonObject.has(typeFieldName)) { + throw new JsonParseException("cannot serialize " + srcType.getName() + + " because it already defines a field named " + typeFieldName); + } + JsonObject clone = new JsonObject(); + clone.add(typeFieldName, new JsonPrimitive(label)); + for (Map.Entry<String, JsonElement> e : jsonObject.entrySet()) { + clone.add(e.getKey(), e.getValue()); + } + Streams.write(clone, out); + } + }.nullSafe(); + } +} diff --git a/extras/src/main/java/com/google/gson/typeadapters/UtcDateTypeAdapter.java b/extras/src/main/java/com/google/gson/typeadapters/UtcDateTypeAdapter.java new file mode 100644 index 00000000..5e8c0cce --- /dev/null +++ b/extras/src/main/java/com/google/gson/typeadapters/UtcDateTypeAdapter.java @@ -0,0 +1,282 @@ +/* + * Copyright (C) 2011 Google Inc. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package com.google.gson.typeadapters; + +import java.io.IOException; +import java.text.ParseException; +import java.text.ParsePosition; +import java.util.Calendar; +import java.util.Date; +import java.util.GregorianCalendar; +import java.util.Locale; +import java.util.TimeZone; + +import com.google.gson.JsonParseException; +import com.google.gson.TypeAdapter; +import com.google.gson.stream.JsonReader; +import com.google.gson.stream.JsonWriter; + +public final class UtcDateTypeAdapter extends TypeAdapter<Date> { + private final TimeZone UTC_TIME_ZONE = TimeZone.getTimeZone("UTC"); + + @Override + public void write(JsonWriter out, Date date) throws IOException { + if (date == null) { + out.nullValue(); + } else { + String value = format(date, true, UTC_TIME_ZONE); + out.value(value); + } + } + + @Override + public Date read(JsonReader in) throws IOException { + try { + switch (in.peek()) { + case NULL: + in.nextNull(); + return null; + default: + String date = in.nextString(); + // Instead of using iso8601Format.parse(value), we use Jackson's date parsing + // This is because Android doesn't support XXX because it is JDK 1.6 + return parse(date, new ParsePosition(0)); + } + } catch (ParseException e) { + throw new JsonParseException(e); + } + } + + // Date parsing code from Jackson databind ISO8601Utils.java + // https://github.com/FasterXML/jackson-databind/blob/master/src/main/java/com/fasterxml/jackson/databind/util/ISO8601Utils.java + private static final String GMT_ID = "GMT"; + + /** + * Format date into yyyy-MM-ddThh:mm:ss[.sss][Z|[+-]hh:mm] + * + * @param date the date to format + * @param millis true to include millis precision otherwise false + * @param tz timezone to use for the formatting (GMT will produce 'Z') + * @return the date formatted as yyyy-MM-ddThh:mm:ss[.sss][Z|[+-]hh:mm] + */ + private static String format(Date date, boolean millis, TimeZone tz) { + Calendar calendar = new GregorianCalendar(tz, Locale.US); + calendar.setTime(date); + + // estimate capacity of buffer as close as we can (yeah, that's pedantic ;) + int capacity = "yyyy-MM-ddThh:mm:ss".length(); + capacity += millis ? ".sss".length() : 0; + capacity += tz.getRawOffset() == 0 ? "Z".length() : "+hh:mm".length(); + StringBuilder formatted = new StringBuilder(capacity); + + padInt(formatted, calendar.get(Calendar.YEAR), "yyyy".length()); + formatted.append('-'); + padInt(formatted, calendar.get(Calendar.MONTH) + 1, "MM".length()); + formatted.append('-'); + padInt(formatted, calendar.get(Calendar.DAY_OF_MONTH), "dd".length()); + formatted.append('T'); + padInt(formatted, calendar.get(Calendar.HOUR_OF_DAY), "hh".length()); + formatted.append(':'); + padInt(formatted, calendar.get(Calendar.MINUTE), "mm".length()); + formatted.append(':'); + padInt(formatted, calendar.get(Calendar.SECOND), "ss".length()); + if (millis) { + formatted.append('.'); + padInt(formatted, calendar.get(Calendar.MILLISECOND), "sss".length()); + } + + int offset = tz.getOffset(calendar.getTimeInMillis()); + if (offset != 0) { + int hours = Math.abs((offset / (60 * 1000)) / 60); + int minutes = Math.abs((offset / (60 * 1000)) % 60); + formatted.append(offset < 0 ? '-' : '+'); + padInt(formatted, hours, "hh".length()); + formatted.append(':'); + padInt(formatted, minutes, "mm".length()); + } else { + formatted.append('Z'); + } + + return formatted.toString(); + } + /** + * Zero pad a number to a specified length + * + * @param buffer buffer to use for padding + * @param value the integer value to pad if necessary. + * @param length the length of the string we should zero pad + */ + private static void padInt(StringBuilder buffer, int value, int length) { + String strValue = Integer.toString(value); + for (int i = length - strValue.length(); i > 0; i--) { + buffer.append('0'); + } + buffer.append(strValue); + } + + /** + * Parse a date from ISO-8601 formatted string. It expects a format + * [yyyy-MM-dd|yyyyMMdd][T(hh:mm[:ss[.sss]]|hhmm[ss[.sss]])]?[Z|[+-]hh:mm]] + * + * @param date ISO string to parse in the appropriate format. + * @param pos The position to start parsing from, updated to where parsing stopped. + * @return the parsed date + * @throws ParseException if the date is not in the appropriate format + */ + private static Date parse(String date, ParsePosition pos) throws ParseException { + Exception fail = null; + try { + int offset = pos.getIndex(); + + // extract year + int year = parseInt(date, offset, offset += 4); + if (checkOffset(date, offset, '-')) { + offset += 1; + } + + // extract month + int month = parseInt(date, offset, offset += 2); + if (checkOffset(date, offset, '-')) { + offset += 1; + } + + // extract day + int day = parseInt(date, offset, offset += 2); + // default time value + int hour = 0; + int minutes = 0; + int seconds = 0; + int milliseconds = 0; // always use 0 otherwise returned date will include millis of current time + if (checkOffset(date, offset, 'T')) { + + // extract hours, minutes, seconds and milliseconds + hour = parseInt(date, offset += 1, offset += 2); + if (checkOffset(date, offset, ':')) { + offset += 1; + } + + minutes = parseInt(date, offset, offset += 2); + if (checkOffset(date, offset, ':')) { + offset += 1; + } + // second and milliseconds can be optional + if (date.length() > offset) { + char c = date.charAt(offset); + if (c != 'Z' && c != '+' && c != '-') { + seconds = parseInt(date, offset, offset += 2); + // milliseconds can be optional in the format + if (checkOffset(date, offset, '.')) { + milliseconds = parseInt(date, offset += 1, offset += 3); + } + } + } + } + + // extract timezone + String timezoneId; + if (date.length() <= offset) { + throw new IllegalArgumentException("No time zone indicator"); + } + char timezoneIndicator = date.charAt(offset); + if (timezoneIndicator == '+' || timezoneIndicator == '-') { + String timezoneOffset = date.substring(offset); + timezoneId = GMT_ID + timezoneOffset; + offset += timezoneOffset.length(); + } else if (timezoneIndicator == 'Z') { + timezoneId = GMT_ID; + offset += 1; + } else { + throw new IndexOutOfBoundsException("Invalid time zone indicator " + timezoneIndicator); + } + + TimeZone timezone = TimeZone.getTimeZone(timezoneId); + if (!timezone.getID().equals(timezoneId)) { + throw new IndexOutOfBoundsException(); + } + + Calendar calendar = new GregorianCalendar(timezone); + calendar.setLenient(false); + calendar.set(Calendar.YEAR, year); + calendar.set(Calendar.MONTH, month - 1); + calendar.set(Calendar.DAY_OF_MONTH, day); + calendar.set(Calendar.HOUR_OF_DAY, hour); + calendar.set(Calendar.MINUTE, minutes); + calendar.set(Calendar.SECOND, seconds); + calendar.set(Calendar.MILLISECOND, milliseconds); + + pos.setIndex(offset); + return calendar.getTime(); + // If we get a ParseException it'll already have the right message/offset. + // Other exception types can convert here. + } catch (IndexOutOfBoundsException e) { + fail = e; + } catch (NumberFormatException e) { + fail = e; + } catch (IllegalArgumentException e) { + fail = e; + } + String input = (date == null) ? null : ('"' + date + "'"); + throw new ParseException("Failed to parse date [" + input + "]: " + fail.getMessage(), pos.getIndex()); + } + + /** + * Check if the expected character exist at the given offset in the value. + * + * @param value the string to check at the specified offset + * @param offset the offset to look for the expected character + * @param expected the expected character + * @return true if the expected character exist at the given offset + */ + private static boolean checkOffset(String value, int offset, char expected) { + return (offset < value.length()) && (value.charAt(offset) == expected); + } + + /** + * Parse an integer located between 2 given offsets in a string + * + * @param value the string to parse + * @param beginIndex the start index for the integer in the string + * @param endIndex the end index for the integer in the string + * @return the int + * @throws NumberFormatException if the value is not a number + */ + private static int parseInt(String value, int beginIndex, int endIndex) throws NumberFormatException { + if (beginIndex < 0 || endIndex > value.length() || beginIndex > endIndex) { + throw new NumberFormatException(value); + } + // use same logic as in Integer.parseInt() but less generic we're not supporting negative values + int i = beginIndex; + int result = 0; + int digit; + if (i < endIndex) { + digit = Character.digit(value.charAt(i++), 10); + if (digit < 0) { + throw new NumberFormatException("Invalid number: " + value); + } + result = -digit; + } + while (i < endIndex) { + digit = Character.digit(value.charAt(i++), 10); + if (digit < 0) { + throw new NumberFormatException("Invalid number: " + value); + } + result *= 10; + result -= digit; + } + return -result; + } +} |