1 files changed, 833 insertions, 0 deletions
diff --git a/gson/src/main/java/com/google/gson/internal/bind/TypeAdapters.java b/gson/src/main/java/com/google/gson/internal/bind/TypeAdapters.java
new file mode 100644
index 00000000..ec7ceb4f
--- /dev/null
+++ b/gson/src/main/java/com/google/gson/internal/bind/TypeAdapters.java
@@ -0,0 +1,833 @@
+/*
+ * 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.internal.bind;
+
+import java.io.IOException;
+import java.math.BigDecimal;
+import java.math.BigInteger;
+import java.net.InetAddress;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.net.URL;
+import java.sql.Timestamp;
+import java.util.BitSet;
+import java.util.Calendar;
+import java.util.Date;
+import java.util.GregorianCalendar;
+import java.util.HashMap;
+import java.util.Locale;
+import java.util.Map;
+import java.util.StringTokenizer;
+import java.util.UUID;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonIOException;
+import com.google.gson.JsonNull;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonPrimitive;
+import com.google.gson.JsonSyntaxException;
+import com.google.gson.TypeAdapter;
+import com.google.gson.TypeAdapterFactory;
+import com.google.gson.annotations.SerializedName;
+import com.google.gson.internal.LazilyParsedNumber;
+import com.google.gson.reflect.TypeToken;
+import com.google.gson.stream.JsonReader;
+import com.google.gson.stream.JsonToken;
+import com.google.gson.stream.JsonWriter;
+
+/**
+ * Type adapters for basic types.
+ */
+public final class TypeAdapters {
+  private TypeAdapters() {
+    throw new UnsupportedOperationException();
+  }
+
+  @SuppressWarnings("rawtypes")
+  public static final TypeAdapter<Class> CLASS = new TypeAdapter<Class>() {
+    @Override
+    public void write(JsonWriter out, Class value) throws IOException {
+      if (value == null) {
+        out.nullValue();
+      } else {
+        throw new UnsupportedOperationException("Attempted to serialize java.lang.Class: "
+            + value.getName() + ". Forgot to register a type adapter?");
+      }
+    }
+    @Override
+    public Class read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      } else {
+        throw new UnsupportedOperationException(
+            "Attempted to deserialize a java.lang.Class. Forgot to register a type adapter?");
+      }
+    }
+  };
+  public static final TypeAdapterFactory CLASS_FACTORY = newFactory(Class.class, CLASS);
+
+  public static final TypeAdapter<BitSet> BIT_SET = new TypeAdapter<BitSet>() {
+    public BitSet read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+
+      BitSet bitset = new BitSet();
+      in.beginArray();
+      int i = 0;
+      JsonToken tokenType = in.peek();
+      while (tokenType != JsonToken.END_ARRAY) {
+        boolean set;
+        switch (tokenType) {
+        case NUMBER:
+          set = in.nextInt() != 0;
+          break;
+        case BOOLEAN:
+          set = in.nextBoolean();
+          break;
+        case STRING:
+          String stringValue = in.nextString();
+          try {
+            set = Integer.parseInt(stringValue) != 0;
+          } catch (NumberFormatException e) {
+            throw new JsonSyntaxException(
+                "Error: Expecting: bitset number value (1, 0), Found: " + stringValue);
+          }
+          break;
+        default:
+          throw new JsonSyntaxException("Invalid bitset value type: " + tokenType);
+        }
+        if (set) {
+          bitset.set(i);
+        }
+        ++i;
+        tokenType = in.peek();
+      }
+      in.endArray();
+      return bitset;
+    }
+
+    public void write(JsonWriter out, BitSet src) throws IOException {
+      if (src == null) {
+        out.nullValue();
+        return;
+      }
+
+      out.beginArray();
+      for (int i = 0; i < src.length(); i++) {
+        int value = (src.get(i)) ? 1 : 0;
+        out.value(value);
+      }
+      out.endArray();
+    }
+  };
+
+  public static final TypeAdapterFactory BIT_SET_FACTORY = newFactory(BitSet.class, BIT_SET);
+
+  public static final TypeAdapter<Boolean> BOOLEAN = new TypeAdapter<Boolean>() {
+    @Override
+    public Boolean read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      } else if (in.peek() == JsonToken.STRING) {
+        // support strings for compatibility with GSON 1.7
+        return Boolean.parseBoolean(in.nextString());
+      }
+      return in.nextBoolean();
+    }
+    @Override
+    public void write(JsonWriter out, Boolean value) throws IOException {
+      if (value == null) {
+        out.nullValue();
+        return;
+      }
+      out.value(value);
+    }
+  };
+
+  /**
+   * Writes a boolean as a string. Useful for map keys, where booleans aren't
+   * otherwise permitted.
+   */
+  public static final TypeAdapter<Boolean> BOOLEAN_AS_STRING = new TypeAdapter<Boolean>() {
+    @Override public Boolean read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      return Boolean.valueOf(in.nextString());
+    }
+
+    @Override public void write(JsonWriter out, Boolean value) throws IOException {
+      out.value(value == null ? "null" : value.toString());
+    }
+  };
+
+  public static final TypeAdapterFactory BOOLEAN_FACTORY
+      = newFactory(boolean.class, Boolean.class, BOOLEAN);
+
+  public static final TypeAdapter<Number> BYTE = new TypeAdapter<Number>() {
+    @Override
+    public Number read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      try {
+        int intValue = in.nextInt();
+        return (byte) intValue;
+      } catch (NumberFormatException e) {
+        throw new JsonSyntaxException(e);
+      }
+    }
+    @Override
+    public void write(JsonWriter out, Number value) throws IOException {
+      out.value(value);
+    }
+  };
+
+  public static final TypeAdapterFactory BYTE_FACTORY
+      = newFactory(byte.class, Byte.class, BYTE);
+
+  public static final TypeAdapter<Number> SHORT = new TypeAdapter<Number>() {
+    @Override
+    public Number read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      try {
+        return (short) in.nextInt();
+      } catch (NumberFormatException e) {
+        throw new JsonSyntaxException(e);
+      }
+    }
+    @Override
+    public void write(JsonWriter out, Number value) throws IOException {
+      out.value(value);
+    }
+  };
+
+  public static final TypeAdapterFactory SHORT_FACTORY
+      = newFactory(short.class, Short.class, SHORT);
+
+  public static final TypeAdapter<Number> INTEGER = new TypeAdapter<Number>() {
+    @Override
+    public Number read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      try {
+        return in.nextInt();
+      } catch (NumberFormatException e) {
+        throw new JsonSyntaxException(e);
+      }
+    }
+    @Override
+    public void write(JsonWriter out, Number value) throws IOException {
+      out.value(value);
+    }
+  };
+
+  public static final TypeAdapterFactory INTEGER_FACTORY
+      = newFactory(int.class, Integer.class, INTEGER);
+
+  public static final TypeAdapter<Number> LONG = new TypeAdapter<Number>() {
+    @Override
+    public Number read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      try {
+        return in.nextLong();
+      } catch (NumberFormatException e) {
+        throw new JsonSyntaxException(e);
+      }
+    }
+    @Override
+    public void write(JsonWriter out, Number value) throws IOException {
+      out.value(value);
+    }
+  };
+
+  public static final TypeAdapter<Number> FLOAT = new TypeAdapter<Number>() {
+    @Override
+    public Number read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      return (float) in.nextDouble();
+    }
+    @Override
+    public void write(JsonWriter out, Number value) throws IOException {
+      out.value(value);
+    }
+  };
+
+  public static final TypeAdapter<Number> DOUBLE = new TypeAdapter<Number>() {
+    @Override
+    public Number read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      return in.nextDouble();
+    }
+    @Override
+    public void write(JsonWriter out, Number value) throws IOException {
+      out.value(value);
+    }
+  };
+
+  public static final TypeAdapter<Number> NUMBER = new TypeAdapter<Number>() {
+    @Override
+    public Number read(JsonReader in) throws IOException {
+      JsonToken jsonToken = in.peek();
+      switch (jsonToken) {
+      case NULL:
+        in.nextNull();
+        return null;
+      case NUMBER:
+        return new LazilyParsedNumber(in.nextString());
+      default:
+        throw new JsonSyntaxException("Expecting number, got: " + jsonToken);
+      }
+    }
+    @Override
+    public void write(JsonWriter out, Number value) throws IOException {
+      out.value(value);
+    }
+  };
+
+  public static final TypeAdapterFactory NUMBER_FACTORY = newFactory(Number.class, NUMBER);
+
+  public static final TypeAdapter<Character> CHARACTER = new TypeAdapter<Character>() {
+    @Override
+    public Character read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      String str = in.nextString();
+      if (str.length() != 1) {
+        throw new JsonSyntaxException("Expecting character, got: " + str);
+      }
+      return str.charAt(0);
+    }
+    @Override
+    public void write(JsonWriter out, Character value) throws IOException {
+      out.value(value == null ? null : String.valueOf(value));
+    }
+  };
+
+  public static final TypeAdapterFactory CHARACTER_FACTORY
+      = newFactory(char.class, Character.class, CHARACTER);
+
+  public static final TypeAdapter<String> STRING = new TypeAdapter<String>() {
+    @Override
+    public String read(JsonReader in) throws IOException {
+      JsonToken peek = in.peek();
+      if (peek == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      /* coerce booleans to strings for backwards compatibility */
+      if (peek == JsonToken.BOOLEAN) {
+        return Boolean.toString(in.nextBoolean());
+      }
+      return in.nextString();
+    }
+    @Override
+    public void write(JsonWriter out, String value) throws IOException {
+      out.value(value);
+    }
+  };
+  
+  public static final TypeAdapter<BigDecimal> BIG_DECIMAL = new TypeAdapter<BigDecimal>() {
+    @Override public BigDecimal read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      try {
+        return new BigDecimal(in.nextString());
+      } catch (NumberFormatException e) {
+        throw new JsonSyntaxException(e);
+      }
+    }
+
+    @Override public void write(JsonWriter out, BigDecimal value) throws IOException {
+      out.value(value);
+    }
+  };
+  
+  public static final TypeAdapter<BigInteger> BIG_INTEGER = new TypeAdapter<BigInteger>() {
+    @Override public BigInteger read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      try {
+        return new BigInteger(in.nextString());
+      } catch (NumberFormatException e) {
+        throw new JsonSyntaxException(e);
+      }
+    }
+
+    @Override public void write(JsonWriter out, BigInteger value) throws IOException {
+      out.value(value);
+    }
+  };
+
+  public static final TypeAdapterFactory STRING_FACTORY = newFactory(String.class, STRING);
+
+  public static final TypeAdapter<StringBuilder> STRING_BUILDER = new TypeAdapter<StringBuilder>() {
+    @Override
+    public StringBuilder read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      return new StringBuilder(in.nextString());
+    }
+    @Override
+    public void write(JsonWriter out, StringBuilder value) throws IOException {
+      out.value(value == null ? null : value.toString());
+    }
+  };
+
+  public static final TypeAdapterFactory STRING_BUILDER_FACTORY =
+    newFactory(StringBuilder.class, STRING_BUILDER);
+
+  public static final TypeAdapter<StringBuffer> STRING_BUFFER = new TypeAdapter<StringBuffer>() {
+    @Override
+    public StringBuffer read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      return new StringBuffer(in.nextString());
+    }
+    @Override
+    public void write(JsonWriter out, StringBuffer value) throws IOException {
+      out.value(value == null ? null : value.toString());
+    }
+  };
+
+  public static final TypeAdapterFactory STRING_BUFFER_FACTORY =
+    newFactory(StringBuffer.class, STRING_BUFFER);
+
+  public static final TypeAdapter<URL> URL = new TypeAdapter<URL>() {
+    @Override
+    public URL read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      String nextString = in.nextString();
+      return "null".equals(nextString) ? null : new URL(nextString);
+    }
+    @Override
+    public void write(JsonWriter out, URL value) throws IOException {
+      out.value(value == null ? null : value.toExternalForm());
+    }
+  };
+
+  public static final TypeAdapterFactory URL_FACTORY = newFactory(URL.class, URL);
+
+  public static final TypeAdapter<URI> URI = new TypeAdapter<URI>() {
+    @Override
+    public URI read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      try {
+        String nextString = in.nextString();
+        return "null".equals(nextString) ? null : new URI(nextString);
+      } catch (URISyntaxException e) {
+        throw new JsonIOException(e);
+      }
+    }
+    @Override
+    public void write(JsonWriter out, URI value) throws IOException {
+      out.value(value == null ? null : value.toASCIIString());
+    }
+  };
+
+  public static final TypeAdapterFactory URI_FACTORY = newFactory(URI.class, URI);
+
+  public static final TypeAdapter<InetAddress> INET_ADDRESS = new TypeAdapter<InetAddress>() {
+    @Override
+    public InetAddress read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      // regrettably, this should have included both the host name and the host address
+      return InetAddress.getByName(in.nextString());
+    }
+    @Override
+    public void write(JsonWriter out, InetAddress value) throws IOException {
+      out.value(value == null ? null : value.getHostAddress());
+    }
+  };
+
+  public static final TypeAdapterFactory INET_ADDRESS_FACTORY =
+    newTypeHierarchyFactory(InetAddress.class, INET_ADDRESS);
+
+  public static final TypeAdapter<UUID> UUID = new TypeAdapter<UUID>() {
+    @Override
+    public UUID read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      return java.util.UUID.fromString(in.nextString());
+    }
+    @Override
+    public void write(JsonWriter out, UUID value) throws IOException {
+      out.value(value == null ? null : value.toString());
+    }
+  };
+
+  public static final TypeAdapterFactory UUID_FACTORY = newFactory(UUID.class, UUID);
+
+  public static final TypeAdapterFactory TIMESTAMP_FACTORY = new TypeAdapterFactory() {
+    @SuppressWarnings("unchecked") // we use a runtime check to make sure the 'T's equal
+    public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
+      if (typeToken.getRawType() != Timestamp.class) {
+        return null;
+      }
+
+      final TypeAdapter<Date> dateTypeAdapter = gson.getAdapter(Date.class);
+      return (TypeAdapter<T>) new TypeAdapter<Timestamp>() {
+        @Override public Timestamp read(JsonReader in) throws IOException {
+          Date date = dateTypeAdapter.read(in);
+          return date != null ? new Timestamp(date.getTime()) : null;
+        }
+
+        @Override public void write(JsonWriter out, Timestamp value) throws IOException {
+          dateTypeAdapter.write(out, value);
+        }
+      };
+    }
+  };
+
+  public static final TypeAdapter<Calendar> CALENDAR = new TypeAdapter<Calendar>() {
+    private static final String YEAR = "year";
+    private static final String MONTH = "month";
+    private static final String DAY_OF_MONTH = "dayOfMonth";
+    private static final String HOUR_OF_DAY = "hourOfDay";
+    private static final String MINUTE = "minute";
+    private static final String SECOND = "second";
+
+    @Override
+    public Calendar read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return  null;
+      }
+      in.beginObject();
+      int year = 0;
+      int month = 0;
+      int dayOfMonth = 0;
+      int hourOfDay = 0;
+      int minute = 0;
+      int second = 0;
+      while (in.peek() != JsonToken.END_OBJECT) {
+        String name = in.nextName();
+        int value = in.nextInt();
+        if (YEAR.equals(name)) {
+          year = value;
+        } else if (MONTH.equals(name)) {
+          month = value;
+        } else if (DAY_OF_MONTH.equals(name)) {
+          dayOfMonth = value;
+        } else if (HOUR_OF_DAY.equals(name)) {
+          hourOfDay = value;
+        } else if (MINUTE.equals(name)) {
+          minute = value;
+        } else if (SECOND.equals(name)) {
+          second = value;
+        }
+      }
+      in.endObject();
+      return new GregorianCalendar(year, month, dayOfMonth, hourOfDay, minute, second);
+    }
+
+    @Override
+    public void write(JsonWriter out, Calendar value) throws IOException {
+      if (value == null) {
+        out.nullValue();
+        return;
+      }
+      out.beginObject();
+      out.name(YEAR);
+      out.value(value.get(Calendar.YEAR));
+      out.name(MONTH);
+      out.value(value.get(Calendar.MONTH));
+      out.name(DAY_OF_MONTH);
+      out.value(value.get(Calendar.DAY_OF_MONTH));
+      out.name(HOUR_OF_DAY);
+      out.value(value.get(Calendar.HOUR_OF_DAY));
+      out.name(MINUTE);
+      out.value(value.get(Calendar.MINUTE));
+      out.name(SECOND);
+      out.value(value.get(Calendar.SECOND));
+      out.endObject();
+    }
+  };
+
+  public static final TypeAdapterFactory CALENDAR_FACTORY =
+    newFactoryForMultipleTypes(Calendar.class, GregorianCalendar.class, CALENDAR);
+
+  public static final TypeAdapter<Locale> LOCALE = new TypeAdapter<Locale>() {
+    @Override
+    public Locale read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      String locale = in.nextString();
+      StringTokenizer tokenizer = new StringTokenizer(locale, "_");
+      String language = null;
+      String country = null;
+      String variant = null;
+      if (tokenizer.hasMoreElements()) {
+        language = tokenizer.nextToken();
+      }
+      if (tokenizer.hasMoreElements()) {
+        country = tokenizer.nextToken();
+      }
+      if (tokenizer.hasMoreElements()) {
+        variant = tokenizer.nextToken();
+      }
+      if (country == null && variant == null) {
+        return new Locale(language);
+      } else if (variant == null) {
+        return new Locale(language, country);
+      } else {
+        return new Locale(language, country, variant);
+      }
+    }
+    @Override
+    public void write(JsonWriter out, Locale value) throws IOException {
+      out.value(value == null ? null : value.toString());
+    }
+  };
+
+  public static final TypeAdapterFactory LOCALE_FACTORY = newFactory(Locale.class, LOCALE);
+
+  public static final TypeAdapter<JsonElement> JSON_ELEMENT = new TypeAdapter<JsonElement>() {
+    @Override public JsonElement read(JsonReader in) throws IOException {
+      switch (in.peek()) {
+      case STRING:
+        return new JsonPrimitive(in.nextString());
+      case NUMBER:
+        String number = in.nextString();
+        return new JsonPrimitive(new LazilyParsedNumber(number));
+      case BOOLEAN:
+        return new JsonPrimitive(in.nextBoolean());
+      case NULL:
+        in.nextNull();
+        return JsonNull.INSTANCE;
+      case BEGIN_ARRAY:
+        JsonArray array = new JsonArray();
+        in.beginArray();
+        while (in.hasNext()) {
+          array.add(read(in));
+        }
+        in.endArray();
+        return array;
+      case BEGIN_OBJECT:
+        JsonObject object = new JsonObject();
+        in.beginObject();
+        while (in.hasNext()) {
+          object.add(in.nextName(), read(in));
+        }
+        in.endObject();
+        return object;
+      case END_DOCUMENT:
+      case NAME:
+      case END_OBJECT:
+      case END_ARRAY:
+      default:
+        throw new IllegalArgumentException();
+      }
+    }
+
+    @Override public void write(JsonWriter out, JsonElement value) throws IOException {
+      if (value == null || value.isJsonNull()) {
+        out.nullValue();
+      } else if (value.isJsonPrimitive()) {
+        JsonPrimitive primitive = value.getAsJsonPrimitive();
+        if (primitive.isNumber()) {
+          out.value(primitive.getAsNumber());
+        } else if (primitive.isBoolean()) {
+          out.value(primitive.getAsBoolean());
+        } else {
+          out.value(primitive.getAsString());
+        }
+
+      } else if (value.isJsonArray()) {
+        out.beginArray();
+        for (JsonElement e : value.getAsJsonArray()) {
+          write(out, e);
+        }
+        out.endArray();
+
+      } else if (value.isJsonObject()) {
+        out.beginObject();
+        for (Map.Entry<String, JsonElement> e : value.getAsJsonObject().entrySet()) {
+          out.name(e.getKey());
+          write(out, e.getValue());
+        }
+        out.endObject();
+
+      } else {
+        throw new IllegalArgumentException("Couldn't write " + value.getClass());
+      }
+    }
+  };
+
+  public static final TypeAdapterFactory JSON_ELEMENT_FACTORY
+      = newTypeHierarchyFactory(JsonElement.class, JSON_ELEMENT);
+
+  private static final class EnumTypeAdapter<T extends Enum<T>> extends TypeAdapter<T> {
+    private final Map<String, T> nameToConstant = new HashMap<String, T>();
+    private final Map<T, String> constantToName = new HashMap<T, String>();
+
+    public EnumTypeAdapter(Class<T> classOfT) {
+      try {
+        for (T constant : classOfT.getEnumConstants()) {
+          String name = constant.name();
+          SerializedName annotation = classOfT.getField(name).getAnnotation(SerializedName.class);
+          if (annotation != null) {
+            name = annotation.value();
+            for (String alternate : annotation.alternate()) {
+              nameToConstant.put(alternate, constant);
+            }
+          }
+          nameToConstant.put(name, constant);
+          constantToName.put(constant, name);
+        }
+      } catch (NoSuchFieldException e) {
+        throw new AssertionError();
+      }
+    }
+    public T read(JsonReader in) throws IOException {
+      if (in.peek() == JsonToken.NULL) {
+        in.nextNull();
+        return null;
+      }
+      return nameToConstant.get(in.nextString());
+    }
+
+    public void write(JsonWriter out, T value) throws IOException {
+      out.value(value == null ? null : constantToName.get(value));
+    }
+  }
+
+  public static final TypeAdapterFactory ENUM_FACTORY = new TypeAdapterFactory() {
+    @SuppressWarnings({"rawtypes", "unchecked"})
+    public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
+      Class<? super T> rawType = typeToken.getRawType();
+      if (!Enum.class.isAssignableFrom(rawType) || rawType == Enum.class) {
+        return null;
+      }
+      if (!rawType.isEnum()) {
+        rawType = rawType.getSuperclass(); // handle anonymous subclasses
+      }
+      return (TypeAdapter<T>) new EnumTypeAdapter(rawType);
+    }
+  };
+
+  public static <TT> TypeAdapterFactory newFactory(
+      final TypeToken<TT> type, final TypeAdapter<TT> typeAdapter) {
+    return new TypeAdapterFactory() {
+      @SuppressWarnings("unchecked") // we use a runtime check to make sure the 'T's equal
+      public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
+        return typeToken.equals(type) ? (TypeAdapter<T>) typeAdapter : null;
+      }
+    };
+  }
+
+  public static <TT> TypeAdapterFactory newFactory(
+      final Class<TT> type, final TypeAdapter<TT> typeAdapter) {
+    return new TypeAdapterFactory() {
+      @SuppressWarnings("unchecked") // we use a runtime check to make sure the 'T's equal
+      public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
+        return typeToken.getRawType() == type ? (TypeAdapter<T>) typeAdapter : null;
+      }
+      @Override public String toString() {
+        return "Factory[type=" + type.getName() + ",adapter=" + typeAdapter + "]";
+      }
+    };
+  }
+
+  public static <TT> TypeAdapterFactory newFactory(
+      final Class<TT> unboxed, final Class<TT> boxed, final TypeAdapter<? super TT> typeAdapter) {
+    return new TypeAdapterFactory() {
+      @SuppressWarnings("unchecked") // we use a runtime check to make sure the 'T's equal
+      public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
+        Class<? super T> rawType = typeToken.getRawType();
+        return (rawType == unboxed || rawType == boxed) ? (TypeAdapter<T>) typeAdapter : null;
+      }
+      @Override public String toString() {
+        return "Factory[type=" + boxed.getName()
+            + "+" + unboxed.getName() + ",adapter=" + typeAdapter + "]";
+      }
+    };
+  }
+
+  public static <TT> TypeAdapterFactory newFactoryForMultipleTypes(final Class<TT> base,
+      final Class<? extends TT> sub, final TypeAdapter<? super TT> typeAdapter) {
+    return new TypeAdapterFactory() {
+      @SuppressWarnings("unchecked") // we use a runtime check to make sure the 'T's equal
+      public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
+        Class<? super T> rawType = typeToken.getRawType();
+        return (rawType == base || rawType == sub) ? (TypeAdapter<T>) typeAdapter : null;
+      }
+      @Override public String toString() {
+        return "Factory[type=" + base.getName()
+            + "+" + sub.getName() + ",adapter=" + typeAdapter + "]";
+      }
+    };
+  }
+
+  public static <TT> TypeAdapterFactory newTypeHierarchyFactory(
+      final Class<TT> clazz, final TypeAdapter<TT> typeAdapter) {
+    return new TypeAdapterFactory() {
+      @SuppressWarnings("unchecked")
+      public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
+        return clazz.isAssignableFrom(typeToken.getRawType()) ? (TypeAdapter<T>) typeAdapter : null;
+      }
+      @Override public String toString() {
+        return "Factory[typeHierarchy=" + clazz.getName() + ",adapter=" + typeAdapter + "]";
+      }
+    };
+  }
+}