sc

sc online tutorial

::: tip Search classes loaded by JVM. :::

sc stands for search class. This command can search all possible classes loaded by JVM and show their information. The supported options are: [d]、[E]、[f] and [x:].

Supported Options

Name	Specification
class-pattern	pattern for the class name
method-pattern	pattern for the method name
`[d]`	print the details of the current class, including its code source, class specification, its class loader and so on.
If a class is loaded by more than one class loader, then the class details will be printed several times
`[E]`	turn on regex match, the default behavior is wildcards match
`[f]`	print the fields info of the current class, MUST be used with `-d` together
`[x:]`	specify the depth of recursive traverse the static fields, the default value is '0' - equivalent to use `toString` to output
`[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)
`[cs <arg>]`	Specify the return value of class's ClassLoader#toString(). Long format is`[classLoaderStr <arg>]`

::: tip class-patten supports full qualified class name, e.g. com.taobao.test.AAA and com/taobao/test/AAA. It also supports the format of 'com/taobao/test/AAA', so that it is convenient to directly copy class name from the exception stack trace without replacing '/' to '.'. :::

::: tip sc turns on matching sub-class match by default, that is, sc will also search the sub classes of the target class too. If exact-match is desired, pls. use options disable-sub-class true. :::

Usage

Wildcards match search

bash

$ sc demo.*
demo.MathGame
Affect(row-cnt:1) cost in 55 ms.

View class details

bash

$ sc -d demo.MathGame
class-info        demo.MathGame
code-source       /private/tmp/math-game.jar
name              demo.MathGame
isInterface       false
isAnnotation      false
isEnum            false
isAnonymousClass  false
isArray           false
isLocalClass      false
isMemberClass     false
isPrimitive       false
isSynthetic       false
simple-name       MathGame
modifier          public
annotation
interfaces
super-class       +-java.lang.Object
class-loader      +-sun.misc.Launcher$AppClassLoader@3d4eac69
                    +-sun.misc.Launcher$ExtClassLoader@66350f69
classLoaderHash   3d4eac69

Affect(row-cnt:1) cost in 875 ms.

View class fields

bash

$ sc -d -f demo.MathGame
class-info        demo.MathGame
code-source       /private/tmp/math-game.jar
name              demo.MathGame
isInterface       false
isAnnotation      false
isEnum            false
isAnonymousClass  false
isArray           false
isLocalClass      false
isMemberClass     false
isPrimitive       false
isSynthetic       false
simple-name       MathGame
modifier          public
annotation
interfaces
super-class       +-java.lang.Object
class-loader      +-sun.misc.Launcher$AppClassLoader@3d4eac69
                    +-sun.misc.Launcher$ExtClassLoader@66350f69
classLoaderHash   3d4eac69
fields            modifierprivate,static
                  type    java.util.Random
                  name    random
                  value   java.util.Random@522b4
                          08a

                  modifierprivate
                  type    int
                  name    illegalArgumentCount


Affect(row-cnt:1) cost in 19 ms.

Search class by ClassLoader#toString (on the premise that a ClassLoader instance whose toString() returns apo has loaded some classes including demo.MathGame, demo.MyBar, demo.MyFoo)
bash
```
$ sc -cs apo *demo*
demo.MathGame
demo.MyBar
demo.MyFoo
Affect(row-cnt:3) cost in 56 ms.
```