【2】拦截器实例1

import lombok.extern.slf4j.Slf4j;
import org.apache.ibatis.cache.CacheKey;
import org.apache.ibatis.executor.Executor;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.mapping.ParameterMapping;
import org.apache.ibatis.plugin.Interceptor;
import org.apache.ibatis.plugin.Intercepts;
import org.apache.ibatis.plugin.Invocation;
import org.apache.ibatis.plugin.Signature;
import org.apache.ibatis.session.ResultHandler;
import org.apache.ibatis.session.RowBounds;
import org.springframework.stereotype.Component;
import java.lang.reflect.Field;
import java.util.Properties;
@Slf4j
@Component
@Intercepts({
       @Signature(type = Executor.class, method = "query", args = {MappedStatement.class, Object.class, RowBounds.class, ResultHandler.class, CacheKey.class, BoundSql.class})
})
public class TenantIntercepter implements Interceptor {
   @Override
   public Object intercept(Invocation invocation) throws Throwable {
       Object[] args = invocation.getArgs();
       MappedStatement mappedStatement = (MappedStatement) args[0];
       Object parameterObject = args[1];
       RowBounds rowBounds = (RowBounds) args[2];
       ResultHandler resultHandler = (ResultHandler) args[3];
       CacheKey cacheKey = (CacheKey) args[4];
       BoundSql boundSql = (BoundSql) args[5];
       Executor executor = (Executor) invocation.getTarget();
       // 如果是KnowledgeFileMapper下的selectPage方法，那么就要修改参数或sql
       String sql = boundSql.getSql();
       String newSql = sql.replace("AND tenant_id = ?", "AND tenant_id in (?, ?)");
       // 生成新的BoundSql
       BoundSql newBoundSql = new BoundSql(mappedStatement.getConfiguration(), newSql,
               boundSql.getParameterMappings(), boundSql.getParameterObject());
       // 赋值
       for (ParameterMapping mapping: boundSql.getParameterMappings()) {
           String prop = mapping.getProperty();
           if (boundSql.hasAdditionalParameter(prop)) {
               newBoundSql.setAdditionalParameter(prop, boundSql.getAdditionalParameter(prop));
           }
       }
       Field field = mappedStatement.getClass().getDeclaredField("boundSql");
       field.setAccessible(true);
       field.set(mappedStatement, newBoundSql);
       return executor.query(mappedStatement, parameterObject, rowBounds, resultHandler, cacheKey, boundSql);
   }
   @Override
   public Object plugin(Object target) {
       return Interceptor.super.plugin(target);
   }
   @Override
   public void setProperties(Properties properties) {
       Interceptor.super.setProperties(properties);
   }
}