public Builder clear() {
        super.clear();
        tag_ = 0L;
        bitField0_ = (bitField0_ & ~0x00000001);
        type_ = org.box2d.proto.Box2D.PbShapeType.CIRCLE;
        bitField0_ = (bitField0_ & ~0x00000002);
        if (centerBuilder_ == null) {
          center_ = org.box2d.proto.Box2D.PbVec2.getDefaultInstance();
        } else {
          centerBuilder_.clear();
        }
        bitField0_ = (bitField0_ & ~0x00000004);
        radius_ = 0F;
        bitField0_ = (bitField0_ & ~0x00000008);
        if (pointsBuilder_ == null) {
          points_ = java.util.Collections.emptyList();
          bitField0_ = (bitField0_ & ~0x00000010);
        } else {
          pointsBuilder_.clear();
        }
        if (normalsBuilder_ == null) {
          normals_ = java.util.Collections.emptyList();
          bitField0_ = (bitField0_ & ~0x00000020);
        } else {
          normalsBuilder_.clear();
        }
        if (centroidBuilder_ == null) {
          centroid_ = org.box2d.proto.Box2D.PbVec2.getDefaultInstance();
        } else {
          centroidBuilder_.clear();
        }
        bitField0_ = (bitField0_ & ~0x00000040);
        return this;
      }