mybatis：SQL拦截器

打印执行的SQL语句

import java.sql.Connection;
import java.text.DateFormat;
import java.util.Date;
import java.util.List;
import java.util.Locale;
import java.util.Properties;

import org.apache.ibatis.executor.statement.StatementHandler;
import org.apache.ibatis.mapping.BoundSql;
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.Plugin;
import org.apache.ibatis.plugin.Signature;
import org.apache.ibatis.reflection.MetaObject;
import org.apache.ibatis.session.Configuration;
import org.apache.ibatis.type.TypeHandlerRegistry;
import org.mybatis.spring.boot.autoconfigure.MybatisProperties;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

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

  private Logger log = LoggerFactory.getLogger(MybatisInterceptor.class);

  @SuppressWarnings("unused")
  @Autowired
  private MybatisProperties mybatisProperties;

  @Override
  public Object intercept(Invocation invocation) throws Throwable {
    try {
      StatementHandler statementHandler = (StatementHandler) invocation.getTarget();
      BoundSql boundSql = statementHandler.getBoundSql(); // BoundSql就是封装myBatis最终产生的sql类
      log.debug(boundSql.getSql());
    } catch (Exception e) {
      log.error(e.toString());
    }
    return invocation.proceed(); // 执行完上面的任务后，不改变原有的sql执行过程
  }

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

  @Override
  public void setProperties(Properties properties) {

  }

  private String getParameterValue(Object obj) {
    String value = null;
    if (obj instanceof String) {
      value = "'" + obj.toString() + "'";
    } else if (obj instanceof Date) {
      DateFormat formatter = DateFormat.getDateTimeInstance(DateFormat.DEFAULT, DateFormat.DEFAULT, Locale.CHINA);
      value = "'" + formatter.format(obj) + "'";
    } else {
      if (obj != null) {
        value = obj.toString();
      } else {
        value = "";
      }

    }
    return value;
  }

  public String showSql(Configuration configuration, BoundSql boundSql) {
    Object parameterObject = boundSql.getParameterObject();
    List<ParameterMapping> parameterMappings = boundSql.getParameterMappings();
    String sql = boundSql.getSql().replaceAll("[\s]+", " ");
    if (!parameterMappings.isEmpty() && parameterObject != null) {
      TypeHandlerRegistry typeHandlerRegistry = configuration.getTypeHandlerRegistry();
      if (typeHandlerRegistry.hasTypeHandler(parameterObject.getClass())) {
        sql = sql.replaceFirst("\?", getParameterValue(parameterObject));
      } else {
        MetaObject metaObject = configuration.newMetaObject(parameterObject);
        for (ParameterMapping parameterMapping : parameterMappings) {
          String propertyName = parameterMapping.getProperty();
          if (metaObject.hasGetter(propertyName)) {
            Object obj = metaObject.getValue(propertyName);
            sql = sql.replaceFirst("\?", getParameterValue(obj));
          } else if (boundSql.hasAdditionalParameter(propertyName)) {
            Object obj = boundSql.getAdditionalParameter(propertyName);
            sql = sql.replaceFirst("\?", getParameterValue(obj));
          }
        }
      }
    }
    return sql;
  }

}