JavaWriter writer = new JavaWriter(out);
Set<Modifier> publicFinal = EnumSet.of(Modifier.PUBLIC, Modifier.FINAL);
Set<Modifier> publicFinalStatic = EnumSet.of(Modifier.PUBLIC, Modifier.FINAL, Modifier.STATIC);
writer.emitJavadoc("Automatically generated file. DO NOT MODIFY")
.emitPackage(mBuildConfigPackageName)
.beginType("BuildConfig", "class", publicFinal);
for (ClassField field : mFields) {
writer.emitField(