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

1 files changed, 12 insertions, 1 deletions

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