caclite parser代码生成详解

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caclite parser代码生成详解

本文代码均已上传到gitee https://gitee.com/shoothzj/calcite-examples caclite的parser代码生成分为如下两个步骤

生成Parse.jj

文件目录如下

├── pom.xml └── src ├── main │ ├── codegen │ │ ├── config.fmpp │ │ ├── includes │ │ │ ├── compoundIdentifier.ftl │ │ │ └── parserImpls.ftl │ │ └── templates │ │ └── Parser.jj

添加calcite dependency

 <dependency> <groupId>org.apache.calcite</groupId> <artifactId>calcite-core</artifactId> </dependency>

配置drill-fmpp-maven-plugin插件如下

 <plugin> <groupId>org.apache.drill.tools</groupId> <artifactId>drill-fmpp-maven-plugin</artifactId> <executions> <execution> <configuration> <config>src/main/codegen/config.fmpp</config> <output>${project.build.directory}/generated-sources/fmpp</output> <templates>src/main/codegen/templates</templates> </configuration> <id>generate-fmpp-sources</id> <phase>validate</phase> <goals> <goal>generate</goal> </goals> </execution> </executions> </plugin>

codegen 模块的文件都拷贝自对应版本的calclite core/src/main/codegen路径 https://github.com/apache/calcite/tree/main/core/src/main/codegen

然后把https://github.com/apache/calcite/blob/main/core/src/main/codegen/default_config.fmpp 中的parser属性与config.fmpp中的parser属性合并。就可以通过mvn package命令生成Parser.jj了。当然，如果有定制化修改的需求，也可以在这个阶段修改config.fmpp

Parser.jj生成java代码

文件目录如下

├── pom.xml ├── src │ ├── main │ │ ├── codegen │ │ │ └── Parser.jj

Parser.jj就是我们上一步生成的Parser.jj，如果有什么想要的定制化修改，也可以在这个步骤改入到Parser.jj中。

添加calcite dependency

 <dependency> <groupId>org.apache.calcite</groupId> <artifactId>calcite-core</artifactId> </dependency>

配置javacc-maven-plugin如下

 <plugin> <groupId>org.codehaus.mojo</groupId> <artifactId>javacc-maven-plugin</artifactId> <executions> <execution> <id>javacc</id> <goals> <goal>javacc</goal> </goals> <configuration> <sourceDirectory>${project.basedir}/src/main/codegen</sourceDirectory> <includes> <include>/Parser.jj</include> </includes> </configuration> </execution> </executions> </plugin>

生成代码

无Parser.jj定制化修改，一步生成

如果不需要对Parser.jj进行定制化修改，那么可以通过连续运行两个插件来生成代码，这里给出pom文件样例，不再赘述

 <plugin> <groupId>org.apache.drill.tools</groupId> <artifactId>drill-fmpp-maven-plugin</artifactId> <executions> <execution> <configuration> <config>src/main/codegen/config.fmpp</config> <output>${project.build.directory}/generated-sources/fmpp</output> <templates>src/main/codegen/templates</templates> </configuration> <id>generate-fmpp-sources</id> <phase>validate</phase> <goals> <goal>generate</goal> </goals> </execution> </executions> </plugin> <plugin> <groupId>org.codehaus.mojo</groupId> <artifactId>javacc-maven-plugin</artifactId> <executions> <execution> <id>javacc</id> <goals> <goal>javacc</goal> </goals> <configuration> <sourceDirectory>${project.build.directory}/generated-sources/fmpp</sourceDirectory> <includes> <include>/Parser.jj</include> </includes> <lookAhead>2</lookAhead> <isStatic>false</isStatic> </configuration> </execution> <execution> <id>javacc-test</id> <phase>generate-test-sources</phase> <goals> <goal>javacc</goal> </goals> <configuration> <sourceDirectory>${project.build.directory}/generated-test-sources/fmpp</sourceDirectory> <outputDirectory>${project.build.directory}/generated-test-sources/javacc</outputDirectory> <includes> <include>/Parser.jj</include> </includes> <isStatic>false</isStatic> <ignoreCase>true</ignoreCase> <unicodeInput>true</unicodeInput> </configuration> </execution> </executions> </plugin>