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jsqlParse分析SQL

jsqlParse分析SQL

作者: anyly | 来源:发表于2019-10-09 14:23 被阅读0次
/**
主程序入口
**/
  @Test
    public void testJsqlParserSql() throws Exception {
        String sql = SqlConfig.HIGHT4;
        Statement statement = CCJSqlParserUtil.parse(sql);
        parseStatement(statement);
        System.out.println("sql:" + statement.toString());
       

    }

    private void parseItemsList(ItemsList itemsList) {
        if (itemsList instanceof SubSelect) {
            parseFromItem((SubSelect) itemsList);
        } else if (itemsList instanceof ExpressionList) {
            ((ExpressionList) itemsList).getExpressions().forEach(expression -> parseExpression(expression));
        } else {
            System.out.println(itemsList.getClass() + ":遇到无法解析的对象:" + Thread.currentThread().getStackTrace()[1].getMethodName());
        }

    }

    private void parseStatement(Statement statement) {
        if (statement instanceof Select) {
            parseSelectBody(((Select) statement).getSelectBody());
        } else if (statement instanceof SubSelect) {
            parseItemsList((SubSelect) statement);
        } else {
            System.out.println(statement.getClass() + ":遇到无法解析的对象:" + Thread.currentThread().getStackTrace()[1].getMethodName());
        }
    }

    private void parseSelectBody(SelectBody selectBody) {
        if (selectBody instanceof PlainSelect) {
            PlainSelect plainSelect = (PlainSelect) selectBody;
            // 主查询
            parseFromItem(plainSelect.getFromItem());
            // 连接
            parseJoin(plainSelect.getJoins());
            // 条件
            parseExpression(plainSelect.getWhere());
            // 子查询
            List<SelectItem> selectItems = plainSelect.getSelectItems();
            if (selectItems.size() > 0) {
                selectItems.forEach(selectItem -> {
                    parseSelectItem(selectItem);
                });
            }
            whereAdd(plainSelect);
        } else if (selectBody instanceof SetOperationList) {
            List<SelectBody> selectBodyList = ((SetOperationList) selectBody).getSelects();
            selectBodyList.forEach(select -> {
                parseSelectBody(select);
            });
            return;
        } else {
            System.out.println(selectBody.getClass() + ":遇到无法解析的对象:" + Thread.currentThread().getStackTrace()[1].getMethodName());
        }

    }

    private void parseJoin(List<Join> joins) {
        if (null != joins && joins.size() > 0) {
            joins.forEach(join -> {
                parseFromItem(join.getRightItem());
            });
        }

    }


    /**
     * 拼接条件
     *
     * @param plainSelect
     */
    private void whereAdd(PlainSelect plainSelect) {
        Expression expression = plainSelect.getWhere();
        String alias = getAlias(plainSelect.getFromItem());
        /*       Expression ex = null;*/
        EqualsTo equalsTo = new EqualsTo();
        equalsTo.setLeftExpression(new Column(alias + "." + "is_delete"));
        equalsTo.setRightExpression(new LongValue("0"));
       /* try {
            ex = CCJSqlParserUtil.parseCondExpression(alias + "." + "is_delete  ='0'");
        } catch (Exception e) {
            e.printStackTrace();
        }*/
        AndExpression andExpression = new AndExpression(expression, equalsTo);
        if (expression != null) {
            plainSelect.setWhere(andExpression);
        } else {
            plainSelect.setWhere(equalsTo);
        }

    }

    private void parseExpression(Expression expression) {
        if (expression instanceof Column || expression instanceof LongValue || expression instanceof StringValue) {
            return;
        }
        if (expression instanceof Function) {
            return;
        }
        if (expression instanceof MinorThanEquals) {
            return;
        } if (expression instanceof JdbcParameter) {
            return;
        }
        if (expression instanceof GreaterThanEquals) {
            return;
        }
        if (expression instanceof Parenthesis) {
            return;
        }
        if (expression instanceof EqualsTo) {
            EqualsTo equalsTo = (EqualsTo) expression;
            Expression leftExpression = equalsTo.getLeftExpression();
            Expression rightExpression = equalsTo.getRightExpression();
            parseExpression(leftExpression);
            parseExpression(rightExpression);
        } else if (expression instanceof AndExpression) {
            AndExpression andExpression = (AndExpression) expression;
            parseExpression(andExpression.getLeftExpression());
            parseExpression(andExpression.getRightExpression());
        } else if (expression instanceof InExpression) {
            InExpression inExpression = (InExpression) expression;
            Expression leftExpression = inExpression.getLeftExpression();
            ItemsList itemsList = inExpression.getRightItemsList();
            parseItemsList(itemsList);
            parseExpression(leftExpression);
        } else if (expression instanceof SubSelect) {
            parseFromItem((SubSelect) expression);
        } else {
            if (expression != null) {
                System.out.println(expression.getClass() + ":遇到无法解析的对象:" + Thread.currentThread().getStackTrace()[1].getMethodName());
            }
        }


    }

    private void parseSelectItem(SelectItem selectItem) {
        if (selectItem instanceof AllTableColumns || selectItem instanceof AllColumns) {
            return;
        }
        if (selectItem instanceof SelectExpressionItem) {
            SelectExpressionItem selectExpressionItem = (SelectExpressionItem) selectItem;
            parseExpression(selectExpressionItem.getExpression());
        } else {
            System.out.println(selectItem.getClass() + ":遇到无法解析的对象:" + Thread.currentThread().getStackTrace()[1].getMethodName());
        }

    }

    /**
     * 获取别名
     *
     * @return
     */
    private String getAlias(FromItem fromItem) {
        if (null != fromItem.getAlias() && null != fromItem.getAlias().getName()) {
            return fromItem.getAlias().getName();
        }
        return fromItem.toString();
    }

    private void parseFromItem(FromItem fromItem) {
        if (fromItem instanceof Table) {
            return;
        }
        if (fromItem instanceof SubSelect) {
            SubSelect subSelect = (SubSelect) fromItem;
            parseSelectBody(subSelect.getSelectBody());
        } else {
            System.out.println("遇到无法解析的对象:" + Thread.currentThread().getStackTrace()[1].getMethodName());
        }
    }
sql可以自己放上去

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