code: public static BlockStmt mergeBlock(BlockStmt one, BlockStmt two) {
  
          if (isAllNull(one, two)) return null;
  
          BlockStmt blockStmt = null;
          if (isAllNotNull(one, two)) {
  
              blockStmt = new BlockStmt();
              blockStmt.setComment(mergeSelective(one.getComment(), two.getComment()));
              blockStmt.setStmts(mergeListInOrder(one.getStmts(), two.getStmts()));
  
          } else {
              blockStmt = findFirstNotNull(one, two);
          }
          return blockStmt;
      }
docs: /*
  合并代码块儿