关于springboot:SpringBoot集成mybatis拦截器修改表名

背景

公司的框架是基于 mysql5.7 开发的，最近有一个利用我的项目部署在 linux 零碎上，应用的是 mysql8.0，装置时未开启大小写敏感疏忽，客户又不容许重装 mysql 环境，导致一些框架代码和业务代码中表名应用大写的中央会呈现表名找不不到的状况，所以须要进行对立解决

自定义 SQLAST 适配器

自定义 ASTVisitorAdapter 对表名进行批改

public class MySqlExportTableAliasVisitor extends MySqlASTVisitorAdapter {
    @Override
    public boolean visit(SQLExprTableSource x) {SystemConfig systemConfig = SpringBootBeanUtil.getBean(SystemConfig.class);
        if(systemConfig.getDbTableNameProxy().equals("lowcase")){x.setExpr(x.getTableName().toLowerCase());
        }else if(systemConfig.getDbTableNameProxy().equals("upcase")){x.setExpr(x.getTableName().toUpperCase());
        }
        return true;
    }
}

自定义 Mybatis 拦截器

通过 BoundSql 获取 sql 语句，应用 Druid 的 SQLUtils 对 sql 语句进行结构化分析，表名批改实现后再从新复制 sql 语句

@Intercepts({@Signature(type = StatementHandler.class, method = "prepare", args = {Connection.class, Integer.class})})
public class SQLTableNameHandleInterceptor implements Interceptor {

    @Override
    public Object intercept(Invocation invocation) throws Throwable {DataBaseInfoUtil dataBaseInfoUtil = SpringBootBeanUtil.getBean(DataBaseInfoUtil.class);
        if(dataBaseInfoUtil.checkOpenTableNameHandle()){StatementHandler statementHandler = (StatementHandler) invocation.getTarget();
            MetaObject metaStatementHandler = MetaObject.forObject(statementHandler, new DefaultObjectFactory(), new DefaultObjectWrapperFactory(), new DefaultReflectorFactory());
            BoundSql boundSql = (BoundSql) metaStatementHandler.getValue("delegate.boundSql");

            String sql = boundSql.getSql();
            List<SQLStatement> stmtList  = SQLUtils.parseStatements(sql, JdbcConstants.MYSQL);
            MySqlExportTableAliasVisitor visitor = new MySqlExportTableAliasVisitor();
            for (SQLStatement stmt : stmtList) {stmt.accept(visitor);
            }
            String handleSQL = SQLUtils.toSQLString(stmtList, JdbcConstants.MYSQL);

            metaStatementHandler.setValue("delegate.boundSql.sql", handleSQL);
        }
        return invocation.proceed();}

    @Override
    public Object plugin(Object target) {return Plugin.wrap(target, this);
    }

    @Override
    public void setProperties(Properties properties) {}}

注册自定义 Myabits 拦截器

@Configuration
public class FrameMyBatisPluginConfig {
    @Bean
    @Conditional({SQLTableNameHandleInterceptorCondition.class})
    public String SQLTableNameHandleInterceptor(SqlSessionFactory sqlSessionFactory) {
        // 实例化插件
        SQLTableNameHandleInterceptor sqlTableNameHandleInterceptor = new SQLTableNameHandleInterceptor();
        // 创立属性值
        Properties properties = new Properties();
        properties.setProperty("prop1","value1");
        // 将属性值设置到插件中
        sqlTableNameHandleInterceptor.setProperties(properties);
        // 将插件增加到 SqlSessionFactory 工厂
        sqlSessionFactory.getConfiguration().addInterceptor(sqlTableNameHandleInterceptor);
        return "interceptor";
    }
}