Java Agent and Javassist modify bytecode to join monitoring

problem description

1. We intend to add some bytecodes for monitoring before the actual operation, such as slow sql , dubbo concurrency , development release time to check mybatis/ibatis configuration files

the environmental background of the problems and what methods you have tried

2. We use Instrumentation to import the Agent jar package that we monitor and develop at startup, but we find that the following code using javassist doesn"t work


    <modelVersion>4.0.0</modelVersion>

    <groupId>top.huzhurong.agent</groupId>
    <artifactId>test</artifactId>
    <version>1.0-SNAPSHOT</version>


    <dependencies>
        <dependency>
            <groupId>org.javassist</groupId>
            <artifactId>javassist</artifactId>
            <version>3.23.1-GA</version>
        </dependency>
    </dependencies>
    
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.6.1</version>
                <configuration>
                    <target>1.8</target>
                    <source>1.8</source>
                    <encoding>utf-8</encoding>
                </configuration>
            </plugin>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <version>2.3.1</version>
                <configuration>
                    <archive>
                        <manifest>
                            <addClasspath>true</addClasspath>
                        </manifest>
                        <manifestEntries>
                            <Premain-Class>test.Agent</Premain-Class>
                            <Boot-Class-Path>javassist-3.23.1-GA.jar</Boot-Class-Path>
                            <Can-Redefine-Classes>true</Can-Redefine-Classes>
                            <Can-Set-Native-Method-Prefix>true</Can-Set-Native-Method-Prefix>
                        </manifestEntries>
                    </archive>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

google, Baidu has not found anything, and it is not easy to debug itself. It was possible to use ASM in the past. Thank you in advance