arthas/arthas-tutorials-en/command/sm/sm.md

Search method from the loaded classes.

sm{{}} stands for search method. This command can search and show method information from all loaded classes. sm{{}} can only view the methods declared on the target class, that is, methods from its parent classes are invisible.

Options

Name	Specification
class-pattern	pattern for class name
method-pattern	pattern for method name
[d]{{}}	print the details of the method
[E]{{}}	turn on regex matching while the default mode is wildcard matching
[c:]{{}}	The hash code of the special class's classLoader
[classLoaderClass:]{{}}	The class name of the ClassLoader that executes the expression.
[n:]{{}}	Maximum number of matching classes with details (100 by default)

sm command Docs

Usage

• View methods of java.lang.String{{}} :

sm java.lang.String{{execute T2}}

• Specify ClassLoader

Find ClassLoaderHash:

sc -d demo.MathGame | grep classLoaderHash{{execute T2}}

• Specify Classloader

Note that the hashcode changes, you need to check the current ClassLoader information first, and extract the hashcode corresponding to the ClassLoader.

if you use-c{{}} , you have to manually type hashcode by -c <hashcode>{{}} .

For classloader with only one instance, it can be specified by --classLoaderClass{{}} using class name, which is more convenient to use.

sm --classLoaderClass sun.misc.Launcher$AppClassLoader demo.MathGame{{execute T2}}

• PS: Here the classLoaderClass in java 8 is sun.misc.Launcher$AppClassLoader, while in java 11 it's jdk.internal.loader.ClassLoaders$AppClassLoader. Currently killercoda using java 11.

The value of --classloaderclass{{}} is the class name of classloader. It can only work when it matches a unique classloader instance. The purpose is to facilitate the input of general commands. However, -c <hashcode>{{}} is dynamic.

• View method java.lang.String#toString{{}} details:

sm -d java.lang.String toString{{execute T2}}