26_ custom system class loader underlying source code analysis methods and analysis forName

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getting APPClassLoader, incoming extcl, as his parents


figure above, set the thread context class loader currently executing, that is, APPClassLoader

The figure above, the security manager of some code

The application is returned class loader

In the ClassLoader

class ClassLoader


above it can be seen that, if (cls! = Null) That is, you can set their own class loader used as a system class loader.
There constructor parameters invoked by reflection custom system class loader, parameters ClassLoader

This is the reason for loading custom placed this configuration method, the method in order to make the reflection in the run method of the ClassLoader call SystemClassLoaderAction

split line------------------------------------------------ ---------------------------
analytical method forName


forName:

return of the caller is calling forName method of that class
returned ccl method is to call forName that kind of class loader

For example: a custom class, called forName (database-driven jdbc link or something)
then the caller is my custom class
ccl class loader is to load my class

Look at this