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author | Feng Xiao <xfxyjwf@gmail.com> | 2016-07-14 15:33:45 -0700 |
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committer | Feng Xiao <xfxyjwf@gmail.com> | 2016-07-14 15:33:45 -0700 |
commit | 1bce70dddb57aa82c3e6a74b072f6a742f47c900 (patch) | |
tree | 9f6b012f5f0d3904ab15ed94ed2ff0405a895358 /src/google | |
parent | 0b6825516b403ce7f9c830074d3cbb5477b4c6a1 (diff) | |
download | protobuf-1bce70dddb57aa82c3e6a74b072f6a742f47c900.tar.gz protobuf-1bce70dddb57aa82c3e6a74b072f6a742f47c900.tar.bz2 protobuf-1bce70dddb57aa82c3e6a74b072f6a742f47c900.zip |
Fix compatiblity issues.
Currently some public API methods are defined in GenreatedMessage.java
and they have a generric return type:
class GeneratedMessage {
class Builder<BuilderType extends Builder<BuilderType>> {
public BuilderType setField(...);
public BuilderType setExtension(...);
}
}
With these definitions, the compiled byte code of a callsite will have
a direct reference to GeneratedMessage. For example:
fooBuilder.setField(...);
becomes:
##: invokevirtual // Method Builder.setField:(...)LGeneratedMessage.Builder
##: checkcast // class Builder
This will prevent us from updating generated classes to subclass a
different versioned GeneratedMessageV3 class in the future (we can't do
it in a binary compatible way).
This change addresses the problem by overriding these methods directly
in the generated class:
class Foo {
class Builder extends GeneratedMessage.Builder<Builder> {
public Builder setField(...) {
return super.setField(...);
}
}
}
After this, fooBuilder.setField(...) will be compiled to:
##: invokevirtual // Method Builder.setField:(...)LFoo.Builder
The callsites will no longer reference GeneratedMessage directly and we
can change Foo to subclass GeneratedMessageV3 without breaking binary
compatiblity.
The downside of this change is:
1. It increases generated code size (though it saves some instructions
on the callsites).
2. We can never stop generating these overrides because doing that
will break binary compatibility.
Change-Id: I879afbbc1325a66324a51565e017143489b06e97
Diffstat (limited to 'src/google')
-rw-r--r-- | src/google/protobuf/compiler/java/java_message_builder.cc | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/src/google/protobuf/compiler/java/java_message_builder.cc b/src/google/protobuf/compiler/java/java_message_builder.cc index b3e9e986..81a70a1f 100644 --- a/src/google/protobuf/compiler/java/java_message_builder.cc +++ b/src/google/protobuf/compiler/java/java_message_builder.cc @@ -181,6 +181,18 @@ Generate(io::Printer* printer) { " return this;\n" "}\n" "\n"); + } else { + printer->Print( + "public final Builder setUnknownFields(\n" + " final com.google.protobuf.UnknownFieldSet unknownFields) {\n" + " return super.setUnknownFields(unknownFields);\n" + "}\n" + "\n" + "public final Builder mergeUnknownFields(\n" + " final com.google.protobuf.UnknownFieldSet unknownFields) {\n" + " return super.mergeUnknownFields(unknownFields);\n" + "}\n" + "\n"); } printer->Print( @@ -438,6 +450,62 @@ GenerateCommonBuilderMethods(io::Printer* printer) { "\n", "classname", name_resolver_->GetImmutableClassName(descriptor_)); + printer->Print( + "public Builder clone() {\n" + " return (Builder) super.clone();\n" + "}\n" + "public Builder setField(\n" + " com.google.protobuf.Descriptors.FieldDescriptor field,\n" + " Object value) {\n" + " return (Builder) super.setField(field, value);\n" + "}\n" + "public Builder clearField(\n" + " com.google.protobuf.Descriptors.FieldDescriptor field) {\n" + " return (Builder) super.clearField(field);\n" + "}\n" + "public Builder clearOneof(\n" + " com.google.protobuf.Descriptors.OneofDescriptor oneof) {\n" + " return (Builder) super.clearOneof(oneof);\n" + "}\n" + "public Builder setRepeatedField(\n" + " com.google.protobuf.Descriptors.FieldDescriptor field,\n" + " int index, Object value) {\n" + " return (Builder) super.setRepeatedField(field, index, value);\n" + "}\n" + "public Builder addRepeatedField(\n" + " com.google.protobuf.Descriptors.FieldDescriptor field,\n" + " Object value) {\n" + " return (Builder) super.addRepeatedField(field, value);\n" + "}\n"); + + if (descriptor_->extension_range_count() > 0) { + printer->Print( + "public <Type> Builder setExtension(\n" + " com.google.protobuf.GeneratedMessage.GeneratedExtension<\n" + " $classname$, Type> extension,\n" + " Type value) {\n" + " return (Builder) super.setExtension(extension, value);\n" + "}\n" + "public <Type> Builder setExtension(\n" + " com.google.protobuf.GeneratedMessage.GeneratedExtension<\n" + " $classname$, java.util.List<Type>> extension,\n" + " int index, Type value) {\n" + " return (Builder) super.setExtension(extension, index, value);\n" + "}\n" + "public <Type> Builder addExtension(\n" + " com.google.protobuf.GeneratedMessage.GeneratedExtension<\n" + " $classname$, java.util.List<Type>> extension,\n" + " Type value) {\n" + " return (Builder) super.addExtension(extension, value);\n" + "}\n" + "public <Type> Builder clearExtension(\n" + " com.google.protobuf.GeneratedMessage.GeneratedExtension<\n" + " $classname$, ?> extension) {\n" + " return (Builder) super.clearExtension(extension);\n" + "}\n", + "classname", name_resolver_->GetImmutableClassName(descriptor_)); + } + // ----------------------------------------------------------------- if (context_->HasGeneratedMethods(descriptor_)) { |