mybatis插件实现自定义改写表名实例代码

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

     @Signature (type = Executor. class , method = "update" , args = {MappedStatement. class , Object. class }),})

public class RerouteToTableInterceptor implements Interceptor {

     private Map map;

     private Set<String> tableSet;

     public static boolean openInterceptor = false ;

     public RerouteToTableInterceptor() {

         //标识使用了该插件

         setOpenInterceptor( true );

     }

     @Override

     public Object intercept(Invocation invocation) throws Throwable {

         Object[] args = invocation.getArgs();

         MappedStatement ms = (MappedStatement) args[ 0 ];

         Object parameterObject = args[ 1 ];

         BoundSql boundSql = ms.getBoundSql(parameterObject);

         String sql = boundSql.getSql();

         MySqlStatementParser mySqlStatementParser = new MySqlStatementParser(sql);

         SQLStatement statement = mySqlStatementParser.parseStatement();

         SQLExprTableSource sqlTableSource = null ;

         if (statement instanceof SQLSelectStatement){

             SQLSelect selectQuery = ((SQLSelectStatement)statement).getSelect();

             MySqlSelectQueryBlock sqlSelectQuery = (MySqlSelectQueryBlock)selectQuery.getQuery();

             sqlTableSource = (SQLExprTableSource)sqlSelectQuery.getFrom();

         } else if (statement instanceof SQLInsertStatement){

             SQLInsertStatement sqlInsertStatement = (SQLInsertStatement)statement;

             sqlTableSource = sqlInsertStatement.getTableSource();

         } else if (statement instanceof SQLUpdateStatement){

             SQLUpdateStatement sqlUpdateStatement = (SQLUpdateStatement)statement;

             sqlTableSource = (SQLExprTableSource)sqlUpdateStatement.getTableSource();

         } else if (statement instanceof SQLDeleteStatement){

             SQLDeleteStatement sqlUpdateStatement = (SQLDeleteStatement)statement;

             sqlTableSource = (SQLExprTableSource)sqlUpdateStatement.getTableSource();

         }

         String tableName = sqlTableSource.toString();

         if (tableSet.contains(tableName)){

             SQLIdentifierExpr sqlExpr = (SQLIdentifierExpr)sqlTableSource.getExpr();

             String newTableName = (String)map.get(tableName);

             if (!StringUtils.isEmpty(newTableName) && null != newTableName)

                 sqlExpr.setName(newTableName);

         }

         BoundSql bs = new BoundSql(ms.getConfiguration(),statement.toString(),boundSql.getParameterMappings(),parameterObject);

         MappedStatement newMs = copyFromMappedStatement(ms, new BoundSqlSqlSource(bs));

         for (ParameterMapping mapping : boundSql.getParameterMappings()) {

             String prop = mapping.getProperty();

             if (boundSql.hasAdditionalParameter(prop)) {

                 bs.setAdditionalParameter(prop, boundSql.getAdditionalParameter(prop));

             }

         }

         args[ 0 ] = newMs;

         return invocation.proceed();

     }

     @Override

     public Object plugin(Object target) {

         return Plugin.wrap(target, this );

     }

     @Override

     public void setProperties(Properties properties) {}

     public Map getMap() {

         return map;

     }

     public void setMap(Map map) {

         tableSet = map.keySet();

         this .map = map;

     }

     public boolean isOpenInterceptor() {

         return openInterceptor;

     }

     public void setOpenInterceptor( boolean openInterceptor) {

         this .openInterceptor = openInterceptor;

     }

     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 && ms.getKeyProperties().length > 0 ) {

             builder.keyProperty(ms.getKeyProperties()[ 0 ]);

         }

         builder.timeout(ms.getTimeout());

         builder.parameterMap(ms.getParameterMap());

         builder.resultMaps(ms.getResultMaps());

         builder.resultSetType(ms.getResultSetType());

         builder.cache(ms.getCache());

         builder.flushCacheRequired(ms.isFlushCacheRequired());

         builder.useCache(ms.isUseCache());

         return builder.build();

     }

     public static class BoundSqlSqlSource implements SqlSource {

         private BoundSql boundSql;

         public BoundSqlSqlSource(BoundSql boundSql) {

             this .boundSql = boundSql;

         }

         public BoundSql getBoundSql(Object parameterObject) {

             return boundSql;

         }

     }

}