1. When running the javacc2_1 class, you need to pay attention to the class path to avoid the error that the main function cannot be found. The most direct way is to put it in the java default path and run it.
2. Two of the classes define variable enum, which is not allowed in higher versions of jdk and needs to be modified manually. When using ant, the corresponding class file must be copied to the corresponding package according to the error message.
3. It’s okay to create an index. For everything else, just follow the installation instructions.
This way you can learn about javacc, ant, and other tools, but another simpler method is to build a project in eclipse, copy the corresponding files to the project, and deploy and debug. At this time, establishing the index requires setting relevant parameters at runtime. Of course, you can also rewrite the class yourself and directly pass in the parameters instead of obtaining them from the main function parameters.