1. Install Arthas

    curl -O https://alibaba.github.io/arthas/arthas-boot.jar
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  2. Start the Arthas

    java -jar arthas-boot.jar
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  3. Select the Java process to operate on

  4. The jad command decompiles the files that need to be changed, saves them, and the compiler modifies them

    jad  --source com.runlion.middleground.user.api.dto.CementRatioInfoDTO > /data/CementRatioInfoDTO.java
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  5. The SC command finds which classLoader loaded the current class

    sc -d com.runlion.middleground.user.api.dto.CementRatioInfoDTO | grep classLoader
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  6. The MC command recompiles the class in memory with the specified classloader

     mc -c 45a37759 /data/CementRatioInfoDTO.java -d /data
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  7. The re-define command loads the compiled class into the JVM

    redefine /data/com/runlion/middleground/user/api/dto/CementRatioInfoDTO.class
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