Default support for BitSet. As well, provide more flexibility on getAsBoolean for a JsonPrimitive.

gson/src/main/java/com/google/gson/DefaultTypeAdapters.java

@@ -17,6 +17,7 @@
 package com.google.gson;
 
 import com.google.gson.internal.$Gson$Types;
+
 import java.lang.reflect.ParameterizedType;
 import java.lang.reflect.Type;
 import java.math.BigDecimal;
@@ -33,6 +34,7 @@ import java.text.DateFormat;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
+import java.util.BitSet;
 import java.util.Calendar;
 import java.util.Collection;
 import java.util.Date;
@@ -74,6 +76,7 @@ final class DefaultTypeAdapters {
   private static final UriTypeAdapter URI_TYPE_ADAPTER = new UriTypeAdapter();
   private static final UuidTypeAdapter UUUID_TYPE_ADAPTER = new UuidTypeAdapter();
   private static final LocaleTypeAdapter LOCALE_TYPE_ADAPTER = new LocaleTypeAdapter();
+  private static final BitSetTypeAdapter BIT_SET_ADAPTER = new BitSetTypeAdapter();
   private static final DefaultInetAddressAdapter INET_ADDRESS_ADAPTER =
       new DefaultInetAddressAdapter();
       private static final CollectionTypeAdapter COLLECTION_TYPE_ADAPTER = new CollectionTypeAdapter();
@@ -129,6 +132,7 @@ final class DefaultTypeAdapters {
     map.register(GregorianCalendar.class, GREGORIAN_CALENDAR_TYPE_ADAPTER);
     map.register(BigDecimal.class, BIG_DECIMAL_TYPE_ADAPTER);
     map.register(BigInteger.class, BIG_INTEGER_TYPE_ADAPTER);
+    map.register(BitSet.class, BIT_SET_ADAPTER);
 
     // Add primitive serializers
     map.register(Boolean.class, BOOLEAN_TYPE_ADAPTER);
@@ -176,6 +180,7 @@ final class DefaultTypeAdapters {
     map.register(GregorianCalendar.class, GREGORIAN_CALENDAR_TYPE_ADAPTER);
     map.register(BigDecimal.class, BIG_DECIMAL_TYPE_ADAPTER);
     map.register(BigInteger.class, BIG_INTEGER_TYPE_ADAPTER);
+    map.register(BitSet.class, BIT_SET_ADAPTER);
 
     // Add primitive deserializers
     map.register(Boolean.class, BOOLEAN_TYPE_ADAPTER);
@@ -530,6 +535,38 @@ final class DefaultTypeAdapters {
     }
   }
 
+  private static final class BitSetTypeAdapter implements JsonSerializer<BitSet>, JsonDeserializer<BitSet> {
+    public JsonElement serialize(BitSet src, Type typeOfSrc, JsonSerializationContext context) {
+      JsonArray array = new JsonArray();
+      for (int i = 0; i < src.length(); i++) {
+        int value = (src.get(i)) ? 1 : 0;
+        array.add(new JsonPrimitive(value));
+      }
+      return array;
+    }
+
+    public BitSet deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context)
+        throws JsonParseException {
+      if (!json.isJsonArray()) {
+        throw new JsonParseException("Expected an array of bits.");
+      }
+      BitSet result = new BitSet();
+      JsonArray array = json.getAsJsonArray();
+      for (int i = 0; i < array.size(); i++) {
+        JsonElement element = array.get(i);
+        if (element.getAsBoolean()) {
+           result.set(i);
+        }
+      }
+      return result;
+    }
+
+    @Override
+    public String toString() {
+      return BitSetTypeAdapter.class.getSimpleName();
+    }
+  }
+
   private static final class UrlTypeAdapter implements JsonSerializer<URL>, JsonDeserializer<URL> {
     public JsonElement serialize(URL src, Type typeOfSrc, JsonSerializationContext context) {
       return new JsonPrimitive(src.toExternalForm());

gson/src/main/java/com/google/gson/JsonPrimitive.java

@@ -126,7 +126,12 @@ public final class JsonPrimitive extends JsonElement {
    */
   @Override
   public boolean getAsBoolean() {
-    return isBoolean() ? getAsBooleanWrapper().booleanValue() : Boolean.parseBoolean(getAsString());
+    if (isBoolean()) {
+      return getAsBooleanWrapper().booleanValue();
+    } else {
+      String stringValue = getAsString();
+      return Boolean.parseBoolean(stringValue) || "1".equals(stringValue);
+    }
   }
 
   /**
@@ -372,7 +377,7 @@ public final class JsonPrimitive extends JsonElement {
     if (primitive.value instanceof Number) {
       Number number = (Number) primitive.value;
       return number instanceof BigInteger || number instanceof Long || number instanceof Integer
-      || number instanceof Short || number instanceof Byte;
+          || number instanceof Short || number instanceof Byte;
     }
     return false;
   }

gson/src/test/java/com/google/gson/JsonPrimitiveTest.java

@@ -17,9 +17,11 @@
 package com.google.gson;
 
 import com.google.gson.common.MoreAsserts;
+
+import junit.framework.TestCase;
+
 import java.math.BigDecimal;
 import java.math.BigInteger;
-import junit.framework.TestCase;
 
 /**
  * Unit test for the {@link JsonPrimitive} class.
@@ -33,6 +35,22 @@ public class JsonPrimitiveTest extends TestCase {
 
     assertTrue(json.isBoolean());
     assertTrue(json.getAsBoolean());
+
+    // Extra support for booleans
+    json = new JsonPrimitive(1);
+    assertTrue(json.getAsBoolean());
+
+    json = new JsonPrimitive("1");
+    assertTrue(json.getAsBoolean());
+
+    json = new JsonPrimitive("true");
+    assertTrue(json.getAsBoolean());
+
+    json = new JsonPrimitive("TrUe");
+    assertTrue(json.getAsBoolean());
+
+    json = new JsonPrimitive("1.3");
+    assertFalse(json.getAsBoolean());
   }
 
   public void testParsingStringAsBoolean() throws Exception {

gson/src/test/java/com/google/gson/functional/DefaultTypeAdaptersTest.java

@@ -22,6 +22,9 @@ import com.google.gson.JsonDeserializer;
 import com.google.gson.JsonElement;
 import com.google.gson.JsonParseException;
 import com.google.gson.reflect.TypeToken;
+
+import junit.framework.TestCase;
+
 import java.lang.reflect.Type;
 import java.math.BigDecimal;
 import java.math.BigInteger;
@@ -32,6 +35,7 @@ import java.sql.Timestamp;
 import java.text.DateFormat;
 import java.text.SimpleDateFormat;
 import java.util.Arrays;
+import java.util.BitSet;
 import java.util.Calendar;
 import java.util.Date;
 import java.util.GregorianCalendar;
@@ -43,7 +47,6 @@ import java.util.Set;
 import java.util.TimeZone;
 import java.util.TreeSet;
 import java.util.UUID;
-import junit.framework.TestCase;
 
 /**
  * Functional test for Json serialization and deserialization for common classes for which default
@@ -208,6 +211,36 @@ public class DefaultTypeAdaptersTest extends TestCase {
     assertEquals("[\"blah\"]", json);
   }
 
+  public void testBitSetSerialization() throws Exception {
+    Gson gson = new Gson();
+    BitSet bits = new BitSet();
+    bits.set(1);
+    bits.set(3, 6);
+    bits.set(9);
+    String json = gson.toJson(bits);
+    assertEquals("[0,1,0,1,1,1,0,0,0,1]", json);
+  }
+
+  public void testBitSetDeserialization() throws Exception {
+    BitSet expected = new BitSet();
+    expected.set(0);
+    expected.set(2, 6);
+    expected.set(8);
+
+    Gson gson = new Gson();
+    String json = gson.toJson(expected);
+    assertEquals(expected, gson.fromJson(json, BitSet.class));
+
+    json = "[1,0,1,1,1,1,0,0,1,0,0,0]";
+    assertEquals(expected, gson.fromJson(json, BitSet.class));
+
+    json = "[\"1\",\"0\",\"1\",\"1\",\"1\",\"1\",\"0\",\"0\",\"1\"]";
+    assertEquals(expected, gson.fromJson(json, BitSet.class));
+
+    json = "[true,false,true,true,true,true,false,false,true,false,false]";
+    assertEquals(expected, gson.fromJson(json, BitSet.class));
+  }
+
   public void testDefaultDateSerialization() {
     Date now = new Date();
     String json = gson.toJson(now);