Implement hashCode() and equals() behind a generator option.

The option is only called 'generate_equals' because:
- equals() is the main thing; hashCode() is there only to
  complement equals();
- it's shorter;
- toString() should not be included in this option because
  it's more for debugging and it's more likely to stop
  ProGuard from working well.

Also shortened the "has bit" expression; was
((bitField & mask) == mask), now ((bitField & mask) != 0).
Both the Java code and the bytecode are slightly shorter.

Change-Id: Ic309a08a60883bf454eb6612679aa99611620e76

13 files changed, 456 insertions, 57 deletions

diff --git a/src/google/protobuf/compiler/javanano/javanano_enum_field.cc b/src/google/protobuf/compiler/javanano/javanano_enum_field.cc
index 3c4b978..b9f4fd0 100644
--- a/src/google/protobuf/compiler/javanano/javanano_enum_field.cc
+++ b/src/google/protobuf/compiler/javanano/javanano_enum_field.cc
@@ -159,8 +159,46 @@ GenerateSerializedSizeCode(io::Printer* printer) const {
   }
 }
 
-string EnumFieldGenerator::GetBoxedType() const {
-  return ClassName(params_, descriptor_->enum_type());
+void EnumFieldGenerator::GenerateEqualsCode(io::Printer* printer) const {
+  if (params_.use_reference_types_for_primitives()) {
+    printer->Print(variables_,
+      "if (this.$name$ == null) {\n"
+      "  if (other.$name$ != null) {\n"
+      "    return false;\n"
+      "  }\n"
+      "} else if (!this.$name$.equals(other.$name$)) {\n"
+      "  return false;"
+      "}\n");
+  } else {
+    // We define equality as serialized form equality. If generate_has(),
+    // then if the field value equals the default value in both messages,
+    // but one's 'has' field is set and the other's is not, the serialized
+    // forms are different and we should return false.
+    printer->Print(variables_,
+      "if (this.$name$ != other.$name$");
+    if (params_.generate_has()) {
+      printer->Print(variables_,
+        "\n"
+        "    || (this.$name$ == $default$\n"
+        "        && this.has$capitalized_name$ != other.has$capitalized_name$)");
+    }
+    printer->Print(") {\n"
+      "  return false;\n"
+      "}\n");
+  }
+}
+
+void EnumFieldGenerator::GenerateHashCodeCode(io::Printer* printer) const {
+  printer->Print(
+    "result = 31 * result + ");
+  if (params_.use_reference_types_for_primitives()) {
+    printer->Print(variables_,
+      "(this.$name$ == null ? 0 : this.$name$)");
+  } else {
+    printer->Print(variables_,
+      "this.$name$");
+  }
+  printer->Print(";\n");
 }
 
 // ===================================================================
@@ -227,8 +265,19 @@ GenerateSerializedSizeCode(io::Printer* printer) const {
     "}\n");
 }
 
-string AccessorEnumFieldGenerator::GetBoxedType() const {
-  return ClassName(params_, descriptor_->enum_type());
+void AccessorEnumFieldGenerator::
+GenerateEqualsCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "if ($different_has$\n"
+    "    || $name$_ != other.$name$_) {\n"
+    "  return false;\n"
+    "}\n");
+}
+
+void AccessorEnumFieldGenerator::
+GenerateHashCodeCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "result = 31 * result + $name$_;\n");
 }
 
 // ===================================================================
@@ -366,8 +415,20 @@ GenerateSerializedSizeCode(io::Printer* printer) const {
   }
 }
 
-string RepeatedEnumFieldGenerator::GetBoxedType() const {
-  return ClassName(params_, descriptor_->enum_type());
+void RepeatedEnumFieldGenerator::
+GenerateEqualsCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "if (!com.google.protobuf.nano.InternalNano.equals(\n"
+    "    this.$name$, other.$name$)) {\n"
+    "  return false;\n"
+    "}\n");
+}
+
+void RepeatedEnumFieldGenerator::
+GenerateHashCodeCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "result = 31 * result\n"
+    "    + com.google.protobuf.nano.InternalNano.hashCode(this.$name$);\n");
 }
 
 }  // namespace javanano
diff --git a/src/google/protobuf/compiler/javanano/javanano_enum_field.h b/src/google/protobuf/compiler/javanano/javanano_enum_field.h
index 934aaaa..af317d8 100644
--- a/src/google/protobuf/compiler/javanano/javanano_enum_field.h
+++ b/src/google/protobuf/compiler/javanano/javanano_enum_field.h
@@ -55,8 +55,8 @@ class EnumFieldGenerator : public FieldGenerator {
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateSerializationCode(io::Printer* printer) const;
   void GenerateSerializedSizeCode(io::Printer* printer) const;
-
-  string GetBoxedType() const;
+  void GenerateEqualsCode(io::Printer* printer) const;
+  void GenerateHashCodeCode(io::Printer* printer) const;
 
  private:
   const FieldDescriptor* descriptor_;
@@ -77,8 +77,8 @@ class AccessorEnumFieldGenerator : public FieldGenerator {
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateSerializationCode(io::Printer* printer) const;
   void GenerateSerializedSizeCode(io::Printer* printer) const;
-
-  string GetBoxedType() const;
+  void GenerateEqualsCode(io::Printer* printer) const;
+  void GenerateHashCodeCode(io::Printer* printer) const;
 
  private:
   const FieldDescriptor* descriptor_;
@@ -98,8 +98,8 @@ class RepeatedEnumFieldGenerator : public FieldGenerator {
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateSerializationCode(io::Printer* printer) const;
   void GenerateSerializedSizeCode(io::Printer* printer) const;
-
-  string GetBoxedType() const;
+  void GenerateEqualsCode(io::Printer* printer) const;
+  void GenerateHashCodeCode(io::Printer* printer) const;
 
  private:
   const FieldDescriptor* descriptor_;
diff --git a/src/google/protobuf/compiler/javanano/javanano_field.h b/src/google/protobuf/compiler/javanano/javanano_field.h
index dad2e7a..150ec19 100644
--- a/src/google/protobuf/compiler/javanano/javanano_field.h
+++ b/src/google/protobuf/compiler/javanano/javanano_field.h
@@ -62,8 +62,8 @@ class FieldGenerator {
   virtual void GenerateMergingCode(io::Printer* printer) const = 0;
   virtual void GenerateSerializationCode(io::Printer* printer) const = 0;
   virtual void GenerateSerializedSizeCode(io::Printer* printer) const = 0;
-
-  virtual string GetBoxedType() const = 0;
+  virtual void GenerateEqualsCode(io::Printer* printer) const = 0;
+  virtual void GenerateHashCodeCode(io::Printer* printer) const = 0;
 
  protected:
   const Params& params_;
diff --git a/src/google/protobuf/compiler/javanano/javanano_generator.cc b/src/google/protobuf/compiler/javanano/javanano_generator.cc
index 48c3a21..5c8bcb6 100644
--- a/src/google/protobuf/compiler/javanano/javanano_generator.cc
+++ b/src/google/protobuf/compiler/javanano/javanano_generator.cc
@@ -125,6 +125,8 @@ bool JavaNanoGenerator::Generate(const FileDescriptor* file,
     } else if (options[i].first == "optional_field_style") {
       params.set_optional_field_accessors(options[i].second == "accessors");
       params.set_use_reference_types_for_primitives(options[i].second == "reftypes");
+    } else if (options[i].first == "generate_equals") {
+      params.set_generate_equals(options[i].second == "true");
     } else {
       *error = "Ignore unknown javanano generator option: " + options[i].first;
     }
diff --git a/src/google/protobuf/compiler/javanano/javanano_helpers.cc b/src/google/protobuf/compiler/javanano/javanano_helpers.cc
index ed6dbd7..95ee670 100644
--- a/src/google/protobuf/compiler/javanano/javanano_helpers.cc
+++ b/src/google/protobuf/compiler/javanano/javanano_helpers.cc
@@ -482,7 +482,7 @@ string GenerateGetBit(int bit_index) {
   int bit_in_var_index = bit_index % 32;
 
   string mask = kBitMasks[bit_in_var_index];
-  string result = "((" + var_name + " & " + mask + ") == " + mask + ")";
+  string result = "((" + var_name + " & " + mask + ") != 0)";
   return result;
 }
 
@@ -504,11 +504,22 @@ string GenerateClearBit(int bit_index) {
   return result;
 }
 
+string GenerateDifferentBit(int bit_index) {
+  string var_name = GetBitFieldNameForBit(bit_index);
+  int bit_in_var_index = bit_index % 32;
+
+  string mask = kBitMasks[bit_in_var_index];
+  string result = "((" + var_name + " & " + mask
+      + ") != (other." + var_name + " & " + mask + "))";
+  return result;
+}
+
 void SetBitOperationVariables(const string name,
     int bitIndex, map<string, string>* variables) {
   (*variables)["get_" + name] = GenerateGetBit(bitIndex);
   (*variables)["set_" + name] = GenerateSetBit(bitIndex);
   (*variables)["clear_" + name] = GenerateClearBit(bitIndex);
+  (*variables)["different_" + name] = GenerateDifferentBit(bitIndex);
 }
 
 }  // namespace javanano
diff --git a/src/google/protobuf/compiler/javanano/javanano_helpers.h b/src/google/protobuf/compiler/javanano/javanano_helpers.h
index cddc077..753a4bd 100644
--- a/src/google/protobuf/compiler/javanano/javanano_helpers.h
+++ b/src/google/protobuf/compiler/javanano/javanano_helpers.h
@@ -141,30 +141,37 @@ string DefaultValue(const Params& params, const FieldDescriptor* field);
 
 // Methods for shared bitfields.
 
-// Gets the name of the shared bitfield for the given index.
+// Gets the name of the shared bitfield for the given field index.
 string GetBitFieldName(int index);
 
 // Gets the name of the shared bitfield for the given bit index.
 // Effectively, GetBitFieldName(bit_index / 32)
 string GetBitFieldNameForBit(int bit_index);
 
-// Generates the java code for the expression that returns the boolean value
-// of the bit of the shared bitfields for the given bit index.
-// Example: "((bitField1_ & 0x04) == 0x04)"
+// Generates the java code for the expression that returns whether the bit at
+// the given bit index is set.
+// Example: "((bitField1_ & 0x04000000) != 0)"
 string GenerateGetBit(int bit_index);
 
-// Generates the java code for the expression that sets the bit of the shared
-// bitfields for the given bit index.
-// Example: "bitField1_ = (bitField1_ | 0x04)"
+// Generates the java code for the expression that sets the bit at the given
+// bit index.
+// Example: "bitField1_ |= 0x04000000"
 string GenerateSetBit(int bit_index);
 
-// Generates the java code for the expression that clears the bit of the shared
-// bitfields for the given bit index.
-// Example: "bitField1_ = (bitField1_ & ~0x04)"
+// Generates the java code for the expression that clears the bit at the given
+// bit index.
+// Example: "bitField1_ = (bitField1_ & ~0x04000000)"
 string GenerateClearBit(int bit_index);
 
-// Sets the 'get_*', 'set_*' and 'clear_*' variables, where * is the given bit
-// field name, to the appropriate Java expressions for the given bit index.
+// Generates the java code for the expression that returns whether the bit at
+// the given bit index contains different values in the current object and
+// another object accessible via the variable 'other'.
+// Example: "((bitField1_ & 0x04000000) != (other.bitField1_ & 0x04000000))"
+string GenerateDifferentBit(int bit_index);
+
+// Sets the 'get_*', 'set_*', 'clear_*' and 'different_*' variables, where * is
+// the given name of the bit, to the appropriate Java expressions for the given
+// bit index.
 void SetBitOperationVariables(const string name,
     int bitIndex, map<string, string>* variables);
 
diff --git a/src/google/protobuf/compiler/javanano/javanano_message.cc b/src/google/protobuf/compiler/javanano/javanano_message.cc
index c55ca55..63f8955 100644
--- a/src/google/protobuf/compiler/javanano/javanano_message.cc
+++ b/src/google/protobuf/compiler/javanano/javanano_message.cc
@@ -198,6 +198,11 @@ void MessageGenerator::Generate(io::Printer* printer) {
 
   GenerateClear(printer);
 
+  if (params_.generate_equals()) {
+    GenerateEquals(printer);
+    GenerateHashCode(printer);
+  }
+
   // If we have an extension range, generate accessors for extensions.
   if (params_.store_unknown_fields()
       && descriptor_->extension_range_count() > 0) {
@@ -326,11 +331,11 @@ void MessageGenerator::GenerateMergeFromMethods(io::Printer* printer) {
   if (params_.store_unknown_fields()) {
     printer->Print(
         "if (unknownFieldData == null) {\n"
-        "  unknownFieldData = \n"
+        "  unknownFieldData =\n"
         "      new java.util.ArrayList<com.google.protobuf.nano.UnknownFieldData>();\n"
         "}\n"
-        "if (!com.google.protobuf.nano.WireFormatNano.storeUnknownField(unknownFieldData, \n"
-        "    input, tag)) {\n"
+        "if (!com.google.protobuf.nano.WireFormatNano.storeUnknownField(\n"
+        "    unknownFieldData, input, tag)) {\n"
         "  return this;\n"
         "}\n");
   } else {
@@ -427,6 +432,79 @@ void MessageGenerator::GenerateClear(io::Printer* printer) {
     "}\n");
 }
 
+void MessageGenerator::GenerateEquals(io::Printer* printer) {
+  // Don't override if there are no fields. We could generate an
+  // equals method that compares types, but often empty messages
+  // are used as namespaces.
+  if (descriptor_->field_count() == 0 && !params_.store_unknown_fields()) {
+    return;
+  }
+
+  printer->Print(
+    "\n"
+    "@Override\n"
+    "public boolean equals(Object o) {\n");
+  printer->Indent();
+  printer->Print(
+    "if (o == this) {\n"
+    "  return true;\n"
+    "}\n"
+    "if (!(o instanceof $classname$)) {\n"
+    "  return false;\n"
+    "}\n"
+    "$classname$ other = ($classname$) o;\n",
+    "classname", descriptor_->name());
+
+  for (int i = 0; i < descriptor_->field_count(); i++) {
+    const FieldDescriptor* field = descriptor_->field(i);
+    field_generators_.get(field).GenerateEqualsCode(printer);
+  }
+
+  if (params_.store_unknown_fields()) {
+    printer->Print(
+      "if (unknownFieldData == null || unknownFieldData.isEmpty()) {\n"
+      "  return other.unknownFieldData == null || other.unknownFieldData.isEmpty();"
+      "} else {\n"
+      "  return unknownFieldData.equals(other.unknownFieldData);\n"
+      "}\n");
+  } else {
+    printer->Print(
+      "return true;\n");
+  }
+
+  printer->Outdent();
+  printer->Print("}\n");
+}
+
+void MessageGenerator::GenerateHashCode(io::Printer* printer) {
+  if (descriptor_->field_count() == 0 && !params_.store_unknown_fields()) {
+    return;
+  }
+
+  printer->Print(
+    "\n"
+    "@Override\n"
+    "public int hashCode() {\n");
+  printer->Indent();
+
+  printer->Print("int result = 17;\n");
+  for (int i = 0; i < descriptor_->field_count(); i++) {
+    const FieldDescriptor* field = descriptor_->field(i);
+    field_generators_.get(field).GenerateHashCodeCode(printer);
+  }
+
+  if (params_.store_unknown_fields()) {
+    printer->Print(
+      "result = 31 * result + (unknownFieldData == null || unknownFieldData.isEmpty()\n"
+      "    ? 0 : unknownFieldData.hashCode());\n");
+  }
+
+  printer->Print("return result;\n");
+
+  printer->Outdent();
+  printer->Print("}\n");
+}
+
 // ===================================================================
 
 }  // namespace javanano
diff --git a/src/google/protobuf/compiler/javanano/javanano_message.h b/src/google/protobuf/compiler/javanano/javanano_message.h
index d59ec9f..f87f84f 100644
--- a/src/google/protobuf/compiler/javanano/javanano_message.h
+++ b/src/google/protobuf/compiler/javanano/javanano_message.h
@@ -36,9 +36,10 @@
 #define GOOGLE_PROTOBUF_COMPILER_JAVA_MESSAGE_H__
 
 #include <string>
-#include <google/protobuf/stubs/common.h>
-#include <google/protobuf/compiler/javanano/javanano_params.h>
+#include <google/protobuf/compiler/javanano/javanano_helpers.h>
 #include <google/protobuf/compiler/javanano/javanano_field.h>
+#include <google/protobuf/compiler/javanano/javanano_params.h>
+#include <google/protobuf/stubs/common.h>
 
 namespace google {
 namespace protobuf {
@@ -76,6 +77,8 @@ class MessageGenerator {
                                  const FieldDescriptor* field);
 
   void GenerateClear(io::Printer* printer);
+  void GenerateEquals(io::Printer* printer);
+  void GenerateHashCode(io::Printer* printer);
 
   const Params& params_;
   const Descriptor* descriptor_;
diff --git a/src/google/protobuf/compiler/javanano/javanano_message_field.cc b/src/google/protobuf/compiler/javanano/javanano_message_field.cc
index 02253f9..9f8298c 100644
--- a/src/google/protobuf/compiler/javanano/javanano_message_field.cc
+++ b/src/google/protobuf/compiler/javanano/javanano_message_field.cc
@@ -126,8 +126,25 @@ GenerateSerializedSizeCode(io::Printer* printer) const {
     "}\n");
 }
 
-string MessageFieldGenerator::GetBoxedType() const {
-  return ClassName(params_, descriptor_->message_type());
+void MessageFieldGenerator::
+GenerateEqualsCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "if (this.$name$ == null) { \n"
+    "  if (other.$name$ != null) {\n"
+    "    return false;\n"
+    "  }\n"
+    "} else {\n"
+    "  if (!this.$name$.equals(other.$name$)) {\n"
+    "    return false;\n"
+    "  }\n"
+    "}\n");
+}
+
+void MessageFieldGenerator::
+GenerateHashCodeCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "result = 31 * result +\n"
+    "    (this.$name$ == null ? 0 : this.$name$.hashCode());\n");
 }
 
 // ===================================================================
@@ -203,8 +220,22 @@ GenerateSerializedSizeCode(io::Printer* printer) const {
     "}\n");
 }
 
-string AccessorMessageFieldGenerator::GetBoxedType() const {
-  return ClassName(params_, descriptor_->message_type());
+void AccessorMessageFieldGenerator::
+GenerateEqualsCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "if ($name$_ == null) {\n"
+    "  if (other.$name$_ != null) {\n"
+    "    return false;\n"
+    "  }\n"
+    "} else if (!$name$_.equals(other.$name$_)) {\n"
+    "  return false;\n"
+    "}\n");
+}
+
+void AccessorMessageFieldGenerator::
+GenerateHashCodeCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "result = 31 * result + ($name$_ == null ? 0 : $name$_.hashCode());\n");
 }
 
 // ===================================================================
@@ -291,8 +322,20 @@ GenerateSerializedSizeCode(io::Printer* printer) const {
     "}\n");
 }
 
-string RepeatedMessageFieldGenerator::GetBoxedType() const {
-  return ClassName(params_, descriptor_->message_type());
+void RepeatedMessageFieldGenerator::
+GenerateEqualsCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "if (!com.google.protobuf.nano.InternalNano.equals(\n"
+    "    this.$name$, other.$name$)) {\n"
+    "  return false;\n"
+    "}\n");
+}
+
+void RepeatedMessageFieldGenerator::
+GenerateHashCodeCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "result = 31 * result\n"
+    "    + com.google.protobuf.nano.InternalNano.hashCode(this.$name$);\n");
 }
 
 }  // namespace javanano
diff --git a/src/google/protobuf/compiler/javanano/javanano_message_field.h b/src/google/protobuf/compiler/javanano/javanano_message_field.h
index 9807513..b724351 100644
--- a/src/google/protobuf/compiler/javanano/javanano_message_field.h
+++ b/src/google/protobuf/compiler/javanano/javanano_message_field.h
@@ -55,8 +55,8 @@ class MessageFieldGenerator : public FieldGenerator {
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateSerializationCode(io::Printer* printer) const;
   void GenerateSerializedSizeCode(io::Printer* printer) const;
-
-  string GetBoxedType() const;
+  void GenerateEqualsCode(io::Printer* printer) const;
+  void GenerateHashCodeCode(io::Printer* printer) const;
 
  private:
   const FieldDescriptor* descriptor_;
@@ -77,8 +77,8 @@ class AccessorMessageFieldGenerator : public FieldGenerator {
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateSerializationCode(io::Printer* printer) const;
   void GenerateSerializedSizeCode(io::Printer* printer) const;
-
-  string GetBoxedType() const;
+  void GenerateEqualsCode(io::Printer* printer) const;
+  void GenerateHashCodeCode(io::Printer* printer) const;
 
  private:
   const FieldDescriptor* descriptor_;
@@ -99,8 +99,8 @@ class RepeatedMessageFieldGenerator : public FieldGenerator {
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateSerializationCode(io::Printer* printer) const;
   void GenerateSerializedSizeCode(io::Printer* printer) const;
-
-  string GetBoxedType() const;
+  void GenerateEqualsCode(io::Printer* printer) const;
+  void GenerateHashCodeCode(io::Printer* printer) const;
 
  private:
   const FieldDescriptor* descriptor_;
diff --git a/src/google/protobuf/compiler/javanano/javanano_params.h b/src/google/protobuf/compiler/javanano/javanano_params.h
index 6e5379c..24aece3 100644
--- a/src/google/protobuf/compiler/javanano/javanano_params.h
+++ b/src/google/protobuf/compiler/javanano/javanano_params.h
@@ -61,6 +61,7 @@ class Params {
   bool java_enum_style_;
   bool optional_field_accessors_;
   bool use_reference_types_for_primitives_;
+  bool generate_equals_;
 
  public:
   Params(const string & base_name) :
@@ -71,7 +72,8 @@ class Params {
     generate_has_(false),
     java_enum_style_(false),
     optional_field_accessors_(false),
-    use_reference_types_for_primitives_(false) {
+    use_reference_types_for_primitives_(false),
+    generate_equals_(false) {
   }
 
   const string& base_name() const {
@@ -186,6 +188,13 @@ class Params {
   bool use_reference_types_for_primitives() const {
     return use_reference_types_for_primitives_;
   }
+
+  void set_generate_equals(bool value) {
+    generate_equals_ = value;
+  }
+  bool generate_equals() const {
+    return generate_equals_;
+  }
 };
 
 }  // namespace javanano
diff --git a/src/google/protobuf/compiler/javanano/javanano_primitive_field.cc b/src/google/protobuf/compiler/javanano/javanano_primitive_field.cc
index 0f7512a..cc5fd45 100644
--- a/src/google/protobuf/compiler/javanano/javanano_primitive_field.cc
+++ b/src/google/protobuf/compiler/javanano/javanano_primitive_field.cc
@@ -404,8 +404,102 @@ GenerateSerializedSizeCode(io::Printer* printer) const {
   }
 }
 
-string PrimitiveFieldGenerator::GetBoxedType() const {
-  return BoxedPrimitiveTypeName(GetJavaType(descriptor_));
+void PrimitiveFieldGenerator::
+GenerateEqualsCode(io::Printer* printer) const {
+  // We define equality as serialized form equality. If generate_has(),
+  // then if the field value equals the default value in both messages,
+  // but one's 'has' field is set and the other's is not, the serialized
+  // forms are different and we should return false.
+  JavaType java_type = GetJavaType(descriptor_);
+  if (java_type == JAVATYPE_BYTES) {
+    printer->Print(variables_,
+      "if (!java.util.Arrays.equals(this.$name$, other.$name$)");
+    if (params_.generate_has()) {
+      printer->Print(variables_,
+        "\n"
+        "    || (java.util.Arrays.equals(this.$name$, $default$)\n"
+        "        && this.has$capitalized_name$ != other.has$capitalized_name$)");
+    }
+    printer->Print(") {\n"
+      "  return false;\n"
+      "}\n");
+  } else if (java_type == JAVATYPE_STRING
+      || params_.use_reference_types_for_primitives()) {
+    printer->Print(variables_,
+      "if (this.$name$ == null) {\n"
+      "  if (other.$name$ != null) {\n"
+      "    return false;\n"
+      "  }\n"
+      "} else if (!this.$name$.equals(other.$name$)");
+    if (params_.generate_has()) {
+      printer->Print(variables_,
+        "\n"
+        "    || (this.$name$.equals($default$)\n"
+        "        && this.has$capitalized_name$ != other.has$capitalized_name$)");
+    }
+    printer->Print(") {\n"
+      "  return false;\n"
+      "}\n");
+  } else {
+    printer->Print(variables_,
+      "if (this.$name$ != other.$name$");
+    if (params_.generate_has()) {
+      printer->Print(variables_,
+        "\n"
+        "    || (this.$name$ == $default$\n"
+        "        && this.has$capitalized_name$ != other.has$capitalized_name$)");
+    }
+    printer->Print(") {\n"
+      "  return false;\n"
+      "}\n");
+  }
+}
+
+void PrimitiveFieldGenerator::
+GenerateHashCodeCode(io::Printer* printer) const {
+  JavaType java_type = GetJavaType(descriptor_);
+  if (java_type == JAVATYPE_BYTES) {
+    printer->Print(variables_,
+      "result = 31 * result + java.util.Arrays.hashCode(this.$name$);\n");
+  } else if (java_type == JAVATYPE_STRING
+      || params_.use_reference_types_for_primitives()) {
+    printer->Print(variables_,
+      "result = 31 * result\n"
+      "    + (this.$name$ == null ? 0 : this.$name$.hashCode());\n");
+  } else {
+    switch (java_type) {
+      // For all Java primitive types below, the hash codes match the
+      // results of BoxedType.valueOf(primitiveValue).hashCode().
+      case JAVATYPE_INT:
+        printer->Print(variables_,
+          "result = 31 * result + this.$name$;\n");
+        break;
+      case JAVATYPE_LONG:
+        printer->Print(variables_,
+          "result = 31 * result\n"
+          "    + (int) (this.$name$ ^ (this.$name$ >>> 32));\n");
+        break;
+      case JAVATYPE_FLOAT:
+        printer->Print(variables_,
+          "result = 31 * result\n"
+          "    + java.lang.Float.floatToIntBits(this.$name$);\n");
+        break;
+      case JAVATYPE_DOUBLE:
+        printer->Print(variables_,
+          "{\n"
+          "  long v = java.lang.Double.doubleToLongBits(this.$name$);\n"
+          "  result = 31 * result + (int) (v ^ (v >>> 32));\n"
+          "}\n");
+        break;
+      case JAVATYPE_BOOLEAN:
+        printer->Print(variables_,
+          "result = 31 * result + (this.$name$ ? 1231 : 1237);\n");
+        break;
+      default:
+        GOOGLE_LOG(ERROR) << "unknown java type for primitive field";
+        break;
+    }
+  }
 }
 
 // ===================================================================
@@ -483,8 +577,87 @@ GenerateSerializedSizeCode(io::Printer* printer) const {
     "}\n");
 }
 
-string AccessorPrimitiveFieldGenerator::GetBoxedType() const {
-  return BoxedPrimitiveTypeName(GetJavaType(descriptor_));
+void AccessorPrimitiveFieldGenerator::
+GenerateEqualsCode(io::Printer* printer) const {
+  switch (GetJavaType(descriptor_)) {
+    // For all Java primitive types below, the hash codes match the
+    // results of BoxedType.valueOf(primitiveValue).hashCode().
+    case JAVATYPE_INT:
+    case JAVATYPE_LONG:
+    case JAVATYPE_FLOAT:
+    case JAVATYPE_DOUBLE:
+    case JAVATYPE_BOOLEAN:
+      printer->Print(variables_,
+        "if ($different_has$\n"
+        "    || $name$_ != other.$name$_) {\n"
+        "  return false;\n"
+        "}\n");
+      break;
+    case JAVATYPE_STRING:
+      // Accessor style would guarantee $name$_ non-null
+      printer->Print(variables_,
+        "if ($different_has$\n"
+        "    || !$name$_.equals(other.$name$_)) {\n"
+        "  return false;\n"
+        "}\n");
+      break;
+    case JAVATYPE_BYTES:
+      // Accessor style would guarantee $name$_ non-null
+      printer->Print(variables_,
+        "if ($different_has$\n"
+        "    || !java.util.Arrays.equals($name$_, other.$name$_)) {\n"
+        "  return false;\n"
+        "}\n");
+      break;
+    default:
+      GOOGLE_LOG(ERROR) << "unknown java type for primitive field";
+      break;
+  }
+}
+
+void AccessorPrimitiveFieldGenerator::
+GenerateHashCodeCode(io::Printer* printer) const {
+  switch (GetJavaType(descriptor_)) {
+    // For all Java primitive types below, the hash codes match the
+    // results of BoxedType.valueOf(primitiveValue).hashCode().
+    case JAVATYPE_INT:
+      printer->Print(variables_,
+        "result = 31 * result + $name$_;\n");
+      break;
+    case JAVATYPE_LONG:
+      printer->Print(variables_,
+        "result = 31 * result + (int) ($name$_ ^ ($name$_ >>> 32));\n");
+      break;
+    case JAVATYPE_FLOAT:
+      printer->Print(variables_,
+        "result = 31 * result +\n"
+        "    java.lang.Float.floatToIntBits($name$_);\n");
+      break;
+    case JAVATYPE_DOUBLE:
+      printer->Print(variables_,
+        "{\n"
+        "  long v = java.lang.Double.doubleToLongBits($name$_);\n"
+        "  result = 31 * result + (int) (v ^ (v >>> 32));\n"
+        "}\n");
+      break;
+    case JAVATYPE_BOOLEAN:
+      printer->Print(variables_,
+        "result = 31 * result + ($name$_ ? 1231 : 1237);\n");
+      break;
+    case JAVATYPE_STRING:
+      // Accessor style would guarantee $name$_ non-null
+      printer->Print(variables_,
+        "result = 31 * result + $name$_.hashCode();\n");
+      break;
+    case JAVATYPE_BYTES:
+      // Accessor style would guarantee $name$_ non-null
+      printer->Print(variables_,
+        "result = 31 * result + java.util.Arrays.hashCode($name$_);\n");
+      break;
+    default:
+      GOOGLE_LOG(ERROR) << "unknown java type for primitive field";
+      break;
+  }
 }
 
 // ===================================================================
@@ -629,8 +802,20 @@ GenerateSerializedSizeCode(io::Printer* printer) const {
     "}\n");
 }
 
-string RepeatedPrimitiveFieldGenerator::GetBoxedType() const {
-  return BoxedPrimitiveTypeName(GetJavaType(descriptor_));
+void RepeatedPrimitiveFieldGenerator::
+GenerateEqualsCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "if (!com.google.protobuf.nano.InternalNano.equals(\n"
+    "    this.$name$, other.$name$)) {\n"
+    "  return false;\n"
+    "}\n");
+}
+
+void RepeatedPrimitiveFieldGenerator::
+GenerateHashCodeCode(io::Printer* printer) const {
+  printer->Print(variables_,
+    "result = 31 * result\n"
+    "    + com.google.protobuf.nano.InternalNano.hashCode(this.$name$);\n");
 }
 
 }  // namespace javanano
diff --git a/src/google/protobuf/compiler/javanano/javanano_primitive_field.h b/src/google/protobuf/compiler/javanano/javanano_primitive_field.h
index b42e2f3..2d2b268 100644
--- a/src/google/protobuf/compiler/javanano/javanano_primitive_field.h
+++ b/src/google/protobuf/compiler/javanano/javanano_primitive_field.h
@@ -55,8 +55,8 @@ class PrimitiveFieldGenerator : public FieldGenerator {
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateSerializationCode(io::Printer* printer) const;
   void GenerateSerializedSizeCode(io::Printer* printer) const;
-
-  string GetBoxedType() const;
+  void GenerateEqualsCode(io::Printer* printer) const;
+  void GenerateHashCodeCode(io::Printer* printer) const;
 
  private:
   void GenerateSerializationConditional(io::Printer* printer) const;
@@ -79,8 +79,8 @@ class AccessorPrimitiveFieldGenerator : public FieldGenerator {
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateSerializationCode(io::Printer* printer) const;
   void GenerateSerializedSizeCode(io::Printer* printer) const;
-
-  string GetBoxedType() const;
+  void GenerateEqualsCode(io::Printer* printer) const;
+  void GenerateHashCodeCode(io::Printer* printer) const;
 
  private:
   const FieldDescriptor* descriptor_;
@@ -100,8 +100,8 @@ class RepeatedPrimitiveFieldGenerator : public FieldGenerator {
   void GenerateMergingCode(io::Printer* printer) const;
   void GenerateSerializationCode(io::Printer* printer) const;
   void GenerateSerializedSizeCode(io::Printer* printer) const;
-
-  string GetBoxedType() const;
+  void GenerateEqualsCode(io::Printer* printer) const;
+  void GenerateHashCodeCode(io::Printer* printer) const;
 
  private:
   void GenerateRepeatedDataSizeCode(io::Printer* printer) const;