Note the problems encountered in using Jxls in the project

Cannot load XLS transformer. Please make sure a Transformer implementation is in classpath

Check whether components such as easyexcel are introduced into the project
if so, it needs to be excluded

<dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>easyexcel</artifactId>
      <version>2.2.10</version>
      <exclusions>
        <exclusion>
          <artifactId>poi</artifactId>
          <groupId>org.apache.poi</groupId>
        </exclusion>
        <exclusion>
          <artifactId>poi-ooxml</artifactId>
          <groupId>org.apache.poi</groupId>
        </exclusion>
        <exclusion>
          <artifactId>poi-ooxml-schemas</artifactId>
          <groupId>org.apache.poi</groupId>
        </exclusion>
      </exclusions>
    </dependency>

Then
the POI component 4 version is introduced

    <dependency>
      <groupId>org.apache.poi</groupId>
      <artifactId>poi</artifactId>
      <version>4.1.2</version>
    </dependency>
    <dependency>
      <groupId>org.apache.poi</groupId>
      <artifactId>poi-ooxml</artifactId>
      <version>4.1.2</version>
    </dependency>
    <dependency>
      <groupId>org.apache.poi</groupId>
      <artifactId>poi-ooxml-schemas</artifactId>
      <version>4.1.2</version>
    </dependency>

Because the project is iterative, complex excel is exported. Easyexcel can not meet the requirements. You can consider processing complex logic in the form of Jxls template.
it can solve the function of Excel processing by block, horizontal and column
official website: http://jxls.sourceforge.net/

In theory, it is not recommended to use several excel components at the same time. The idea plug-in Maven helper is recommended here to facilitate conflict handling.

When a problem is inexplicable and can not be solved by how to change it, see if there is a package conflict and if there is a problem with the network itself.