时间:2021-01-13 09:58:05 | 栏目:JAVA代码 | 点击:次
场景:
系统模块查询数据库需要根据用户的id去筛选数据。那么如果在 每个sql加user_id的过滤显然不明确。所以要在查询前将sql拼接上条件,做统一管理。
开发环境:
spring boot + mybatis
只需一个拦截类即可搞定(在看代码前需要了解注解@Intercepts()):
@Component @Intercepts({ @Signature(type = Executor.class, method = "query", args = {MappedStatement.class, Object.class, RowBounds.class, ResultHandler.class }) }) public class SqlInterceptor implements Interceptor { private Logger logger = LoggerFactory.getLogger(SqlInterceptor.class); @Override public Object intercept(Invocation invocation) throws Throwable { logger.info("Interceptor......"); // 获取sql MappedStatement mappedStatement = (MappedStatement) invocation.getArgs()[0]; Object parameter = invocation.getArgs()[1]; BoundSql boundSql = mappedStatement.getBoundSql(parameter); String oldsql = boundSql.getSql(); logger.info("old:"+oldsql); // 判断sql是否有where条件。改变sql。 boolean status = oldsql.toLowerCase().contains("where"); if (status) { BoundSql newBoundSql = new BoundSql(mappedStatement.getConfiguration(), oldsql + " and 1=1", boundSql.getParameterMappings(), boundSql.getParameterObject()); MappedStatement newMs = copyFromMappedStatement(mappedStatement, new BoundSqlSqlSource(newBoundSql)); invocation.getArgs()[0] = newMs; } // 继续执行 Object result = invocation.proceed(); return result; } @Override public Object plugin(Object target) { return Plugin.wrap(target, this); } @Override public void setProperties(Properties properties) { } // 复制原始MappedStatement 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; } } }
这样重启访问即可发现每次查询都会走这边!