Performance fixes after doing some profiling.

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

@@ -429,7 +429,7 @@ final class DefaultTypeAdapters {
       return new LinkedList();
     }    
   }
-  
+
   private static class PropertiesCreator implements InstanceCreator<Properties> {
     public Properties createInstance(Type type) {
       return new Properties();

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

@@ -18,7 +18,6 @@ package com.google.gson;
 
 import java.lang.reflect.Field;
 import java.util.Collection;
-import java.util.LinkedList;
 
 /**
  * A wrapper class used to collect numerous {@link ExclusionStrategy} objects
@@ -29,22 +28,9 @@ import java.util.LinkedList;
 final class DisjunctionExclusionStrategy implements ExclusionStrategy {
   private final Collection<ExclusionStrategy> strategies;
 
-  public DisjunctionExclusionStrategy(ExclusionStrategy... strategies) {
-    Preconditions.checkNotNull(strategies);
-    Preconditions.checkArgument(strategies.length > 0);
-
-    this.strategies = new LinkedList<ExclusionStrategy>();
-    for (ExclusionStrategy strategy : strategies) {
-      this.strategies.add(strategy);
-    }
-  }
-
   public DisjunctionExclusionStrategy(Collection<ExclusionStrategy> strategies) {
     Preconditions.checkNotNull(strategies);
-    Preconditions.checkArgument(!strategies.isEmpty());
-
-    this.strategies = new LinkedList<ExclusionStrategy>();
-    this.strategies.addAll(strategies);
+    this.strategies = strategies;
   }
 
   public boolean shouldSkipField(Field f) {

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

@@ -140,7 +140,7 @@ public final class Gson {
    */
   Gson(ExclusionStrategy strategy, FieldNamingStrategy fieldNamingPolicy) {
     this(strategy, fieldNamingPolicy, 
-        createObjectConstructor(DefaultTypeAdapters.getDefaultInstanceCreators()),
+        new MappedObjectConstructor(DefaultTypeAdapters.getDefaultInstanceCreators()),
         DEFAULT_JSON_FORMATTER, false, DefaultTypeAdapters.getDefaultSerializers(),
         DefaultTypeAdapters.getDefaultDeserializers());
   }
@@ -158,15 +158,6 @@ public final class Gson {
     this.deserializers = deserializers;
   }
   
-  static MappedObjectConstructor createObjectConstructor(
-      ParameterizedTypeHandlerMap<InstanceCreator<?>> instanceCreators) {
-    MappedObjectConstructor objectConstructor = new MappedObjectConstructor();
-    for (Map.Entry<Type, InstanceCreator<?>> entry : instanceCreators.entrySet()) {
-      objectConstructor.register(entry.getKey(), entry.getValue());
-    }
-    return objectConstructor;
-  }
-
   private ObjectNavigatorFactory createDefaultObjectNavigatorFactory() {
     return new ObjectNavigatorFactory(strategy, fieldNamingPolicy);
   }

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

@@ -50,12 +50,16 @@ import com.google.gson.DefaultTypeAdapters.DefaultDateTypeAdapter;
  * @author Joel Leitch
  */
 public final class GsonBuilder {
-
+  private static final AnonymousAndLocalClassExclusionStrategy anonAndLocalClassExclusionStrategy =
+      new AnonymousAndLocalClassExclusionStrategy();
+  private static final InnerClassExclusionStrategy innerClassExclusionStrategy =
+      new InnerClassExclusionStrategy();
+  private static final ExposeAnnotationBasedExclusionStrategy exposeAnnotationExclusionStrategy =
+      new ExposeAnnotationBasedExclusionStrategy();
+  
   private double ignoreVersionsAfter;
   private ModifierBasedExclusionStrategy modifierBasedExclusionStrategy;
   private boolean serializeInnerClasses;
-  private final AnonymousAndLocalClassExclusionStrategy anonAndLocalClassExclusionStrategy;
-  private final InnerClassExclusionStrategy innerClassExclusionStrategy;
   private boolean excludeFieldsWithoutExposeAnnotation;
   private LongSerializationPolicy longSerializationPolicy;
   private FieldNamingStrategy fieldNamingPolicy;
@@ -82,8 +86,6 @@ public final class GsonBuilder {
     serializeInnerClasses = true;
     prettyPrinting = false;
     escapeHtmlChars = true;
-    anonAndLocalClassExclusionStrategy = new AnonymousAndLocalClassExclusionStrategy();
-    innerClassExclusionStrategy = new InnerClassExclusionStrategy();
     modifierBasedExclusionStrategy = Gson.DEFAULT_MODIFIER_BASED_EXCLUSION_STRATEGY;
     excludeFieldsWithoutExposeAnnotation = false;
     longSerializationPolicy = LongSerializationPolicy.DEFAULT;
@@ -399,7 +401,7 @@ public final class GsonBuilder {
       strategies.add(new VersionExclusionStrategy(ignoreVersionsAfter));
     }
     if (excludeFieldsWithoutExposeAnnotation) {
-      strategies.add(new ExposeAnnotationBasedExclusionStrategy());
+      strategies.add(exposeAnnotationExclusionStrategy);
     }
     ExclusionStrategy exclusionStrategy = new DisjunctionExclusionStrategy(strategies);
 
@@ -414,9 +416,14 @@ public final class GsonBuilder {
     customDeserializers.registerIfAbsent(DefaultTypeAdapters.getDefaultDeserializers());
 
     ParameterizedTypeHandlerMap<InstanceCreator<?>> customInstanceCreators =
-      instanceCreators.copyOf();
+        instanceCreators.copyOf();
     customInstanceCreators.registerIfAbsent(DefaultTypeAdapters.getDefaultInstanceCreators());
-    MappedObjectConstructor objConstructor = Gson.createObjectConstructor(customInstanceCreators);
+    
+    customSerializers.makeUnmodifiable();
+    customDeserializers.makeUnmodifiable();
+    instanceCreators.makeUnmodifiable();
+    
+    MappedObjectConstructor objConstructor = new MappedObjectConstructor(customInstanceCreators);
 
     JsonFormatter formatter =  prettyPrinting ?
         new JsonPrintFormatter(escapeHtmlChars) : new JsonCompactFormatter(escapeHtmlChars);
@@ -428,18 +435,20 @@ public final class GsonBuilder {
   private static void addTypeAdaptersForDate(String datePattern, int dateStyle, int timeStyle,
       ParameterizedTypeHandlerMap<JsonSerializer<?>> serializers,
       ParameterizedTypeHandlerMap<JsonDeserializer<?>> deserializers) {
-    // NOTE: if a date pattern exists, then that style takes priority
-    DefaultDateTypeAdapter dateTypeAdapter = null;
-    if (datePattern != null && !"".equals(datePattern.trim())) {
-      dateTypeAdapter = new DefaultDateTypeAdapter(datePattern);
-    } else if (dateStyle != DateFormat.DEFAULT && timeStyle != DateFormat.DEFAULT) {
-      dateTypeAdapter = new DefaultDateTypeAdapter(dateStyle, timeStyle);
-    }
-    if (dateTypeAdapter != null
-        && !serializers.hasSpecificHandlerFor(Date.class)
+    if (!serializers.hasSpecificHandlerFor(Date.class)
         && !deserializers.hasSpecificHandlerFor(Date.class)) {
-      serializers.register(Date.class, dateTypeAdapter);
-      deserializers.register(Date.class, dateTypeAdapter);
+      // NOTE: if a date pattern exists, then that style takes priority
+      DefaultDateTypeAdapter dateTypeAdapter = null;
+      if (datePattern != null && !"".equals(datePattern.trim())) {
+        dateTypeAdapter = new DefaultDateTypeAdapter(datePattern);
+      } else if (dateStyle != DateFormat.DEFAULT && timeStyle != DateFormat.DEFAULT) {
+        dateTypeAdapter = new DefaultDateTypeAdapter(dateStyle, timeStyle);
+      }
+      
+      if (dateTypeAdapter != null) {
+        serializers.register(Date.class, dateTypeAdapter);
+        deserializers.register(Date.class, dateTypeAdapter);
+      }
     }
   }
 }

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

@@ -96,7 +96,7 @@ final class JsonTreeNavigator {
     if (child.isJsonNull()) {
       visitor.visitNullArrayMember(parent, isFirst);
       navigate(child);
-	} else if (child.isJsonArray()) {
+	  } else if (child.isJsonArray()) {
       JsonArray childAsArray = child.getAsJsonArray();
       visitor.visitArrayMember(parent, childAsArray, isFirst);
       navigate(childAsArray);

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

@@ -37,8 +37,12 @@ import java.util.logging.Logger;
 final class MappedObjectConstructor implements ObjectConstructor {
   private static final Logger log = Logger.getLogger(MappedObjectConstructor.class.getName());
 
-  private final ParameterizedTypeHandlerMap<InstanceCreator<?>> instanceCreatorMap =
-      new ParameterizedTypeHandlerMap<InstanceCreator<?>>();
+  private final ParameterizedTypeHandlerMap<InstanceCreator<?>> instanceCreatorMap;
+  
+  public MappedObjectConstructor(
+      ParameterizedTypeHandlerMap<InstanceCreator<?>> instanceCreators) {
+    instanceCreatorMap = instanceCreators;
+  }
 
   @SuppressWarnings("unchecked")
   public <T> T construct(Type typeOfT) {

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

@@ -46,18 +46,6 @@ final class ObjectNavigatorFactory {
     this.stack = new MemoryRefStack<Object>();
   }
 
-  /**
-   * Creates a new {@link ObjectNavigator} for this {@code srcObject}.
-   *
-   * @see #create(Object, Type)
-   * @param srcObject object to navigate
-   * @return a new instance of a {@link ObjectNavigator} ready to navigate the
-   *         {@code srcObject}.
-   */
-  public ObjectNavigator create(Object srcObject) {
-    return create(srcObject, srcObject.getClass());
-  }
-
   /**
    * Creates a new {@link ObjectNavigator} for this {@code srcObject},
    * {@code type} pair.

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

@@ -38,41 +38,26 @@ public class DisjunctionExclusionStrategyTest extends TestCase {
   private static final Field FIELD = CLAZZ.getFields()[0];
 
   public void testBadInstantiation() throws Exception {
-    try {
-      new DisjunctionExclusionStrategy();
-    } catch (IllegalArgumentException expected) { }
-
-    try {
-      ExclusionStrategy[] constructorParam = null;
-      new DisjunctionExclusionStrategy(constructorParam);
-    } catch (IllegalArgumentException expected) { }
-
-    try {
-      ExclusionStrategy[] constructorParam = new ExclusionStrategy[0];
-      new DisjunctionExclusionStrategy(constructorParam);
-    } catch (IllegalArgumentException expected) { }
-
     try {
       List<ExclusionStrategy> constructorParam = null;
       new DisjunctionExclusionStrategy(constructorParam);
     } catch (IllegalArgumentException expected) { }
-
-    try {
-      List<ExclusionStrategy> constructorParam = new LinkedList<ExclusionStrategy>();
-      new DisjunctionExclusionStrategy(constructorParam);
-    } catch (IllegalArgumentException expected) { }
   }
 
   public void testSkipFieldsWithMixedTrueAndFalse() throws Exception {
-    DisjunctionExclusionStrategy strategy =
-        new DisjunctionExclusionStrategy(FALSE_STRATEGY, TRUE_STRATEGY);
+    List<ExclusionStrategy> strategies = new LinkedList<ExclusionStrategy>();
+    strategies.add(FALSE_STRATEGY);
+    strategies.add(TRUE_STRATEGY);
+    DisjunctionExclusionStrategy strategy = new DisjunctionExclusionStrategy(strategies);
 
     assertTrue(strategy.shouldSkipClass(CLAZZ));
     assertTrue(strategy.shouldSkipField(FIELD));
   }
 
   public void testSkipFieldsWithFalseOnly() throws Exception {
-    DisjunctionExclusionStrategy strategy =  new DisjunctionExclusionStrategy(FALSE_STRATEGY);
+    List<ExclusionStrategy> strategies = new LinkedList<ExclusionStrategy>();
+    strategies.add(FALSE_STRATEGY);
+    DisjunctionExclusionStrategy strategy =  new DisjunctionExclusionStrategy(strategies);
 
     assertFalse(strategy.shouldSkipClass(CLAZZ));
     assertFalse(strategy.shouldSkipField(FIELD));