mybatis Interceptor拦截器实现自定义扩展查询兼容mybatis plus

mybatis Interceptor拦截器实现自定义扩展查询兼容mybatis plus
 

@Intercepts({
        @Signature(type = Executor.class,method = "query",args = {MappedStatement.class,Object.class, RowBounds.class, ResultHandler.class})
})
@Slf4j
public class MybatisListSelectFilterInterceptor implements Interceptor {

    @Override
    public Object intercept(Invocation invocation) throws Throwable {

        // 获取原始sql语句
        MappedStatement mappedStatement = (MappedStatement) invocation.getArgs()[0];
        Object parameter = invocation.getArgs()[1];
        if (parameter instanceof SelectFilter){
            BoundSql boundSql = mappedStatement.getBoundSql(parameter);
            SelectFilter selectFilter =(SelectFilter)boundSql.getParameterObject();
            dealSelectFilter(mappedStatement,parameter,selectFilter,invocation);
        }
        // 继续执行
        Object result = invocation.proceed();
        return result;
    }

    private void dealSelectFilter(MappedStatement mappedStatement,Object parameter,SelectFilter selectFilter,Invocation invocation){
        BoundSql boundSql = mappedStatement.getBoundSql(parameter);
        String oldsql = boundSql.getSql();
        log.info("old:"+oldsql);

        Class entityClass = selectFilter.getEntityClass();
        TableName tableNameAnnotation = (TableName) entityClass.getDeclaredAnnotation(TableName.class);
        String tableName = tableNameAnnotation.value();
        Matcher matcher = Pattern.compile("^select\\s+\\*\\s+from\\s+" + tableName).matcher(oldsql.toLowerCase());
        if (matcher.find()){
            StringBuffer sqlBuilder=new StringBuffer();
            Field[] declaredFields = entityClass.getDeclaredFields();
            sqlBuilder.append("select ");
            List<String> fields=new ArrayList<>();
            for (Field declaredField : declaredFields) {
                TableField tableField = declaredField.getAnnotation(TableField.class);
                if (Objects.nonNull(tableField)&&tableField.exist()){
                    String name = declaredField.getName();
                    fields.add(tableField.value()+" "+name);
                }
            }
            String join = String.join(",", fields);
            sqlBuilder.append(join);
            sqlBuilder.append(" from ").append(tableName).append(" ");
            oldsql=sqlBuilder.toString();
        }

        selectFilter.buildWithWhere();
        List<ParameterMapping> parameterMappingList=new ArrayList<>();

        for (Object key : selectFilter.getSqlParamsMap().keySet()) {
            parameterMappingList.add(new ParameterMapping.Builder(mappedStatement.getConfiguration(),"sqlParamsMap."+key,Object.class).build());
        }

        BoundSql newBoundSql = new BoundSql(mappedStatement.getConfiguration(), oldsql + selectFilter.getSql(),
                parameterMappingList, boundSql.getParameterObject());
        MappedStatement newMs = copyFromMappedStatement(mappedStatement, new BoundSqlSqlSource(newBoundSql));
        invocation.getArgs()[0] = newMs;
    }


    /**
     * 复制原始MappedStatement
     * @param ms
     * @param newSqlSource
     * @return
     */
    private MappedStatement copyFromMappedStatement(MappedStatement ms, SqlSource newSqlSource) {
        MappedStatement.Builder builder = new MappedStatement.Builder(ms.getConfiguration(), ms.getId(), newSqlSource,
                ms.getSqlCommandType());
        builder.resource(ms.getResource());
        builder.fetchSize(ms.getFetchSize());
        builder.statementType(ms.getStatementType());
        builder.keyGenerator(ms.getKeyGenerator());
        if (ms.getKeyProperties() != null) {
            for (String keyProperty : ms.getKeyProperties()) {
                builder.keyProperty(keyProperty);
            }
        }
        builder.timeout(ms.getTimeout());
        builder.parameterMap(ms.getParameterMap());
        builder.resultMaps(ms.getResultMaps());
        builder.cache(ms.getCache());
        builder.useCache(ms.isUseCache());
        return builder.build();
    }

    public static class BoundSqlSqlSource implements SqlSource {
        BoundSql boundSql;

        public BoundSqlSqlSource(BoundSql boundSql) {
            this.boundSql = boundSql;
        }

        public BoundSql getBoundSql(Object parameterObject) {
            return boundSql;
        }
    }

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

以上拦截器通过拦截 SelectFilter参数对象进行自定义扩展查询，通过SelectFilter来构建where后面的语句

拦截器注册：

@Configuration
public class MybatisSelectFilterConfiguration {
    @Autowired
    private List<SqlSessionFactory> sqlSessionFactoryList;

    @PostConstruct
    public void addInterceptor() {

        MybatisListSelectFilterInterceptor listSelectFilterInterceptor=new MybatisListSelectFilterInterceptor();
        MybatisPageSelectFilterInterceptor pageSelectFilterInterceptor=new MybatisPageSelectFilterInterceptor();
        sqlSessionFactoryList.forEach(sqlSessionFactory -> {
            sqlSessionFactory.getConfiguration().addInterceptor(listSelectFilterInterceptor);
            sqlSessionFactory.getConfiguration().addInterceptor(pageSelectFilterInterceptor);
        });
    }
}

Mapper 方法

    @Select("select * from cy_xlxw")
    List<Xlxw> list(SelectFilter<Xlxw> selectFilter);

SelectFilter 代码：

mybatis拦截器 mybatis自定义查询 mybatis扩展查询 mybatis plus

https://www.leftso.com/article/1028.html