Custom Class Loader

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Custom Class Loader
This is the manual for older MicroStream versions (Version < 5.0).
The new documentation (Version >= 5.0) is located at:
​https://docs.microstream.one/​
In certain environments or setups it is necessary to provide specific ClassLoader instances. This can be done by customizing the connection foundation.
If a single ClassLoader is sufficient, just create a new provider by handing over the instance:
EmbeddedStorageManager storage = EmbeddedStorage.Foundation(Paths.get("mydb"))
    .onConnectionFoundation(cf -> 
        cf.setClassLoaderProvider(ClassLoaderProvider.New(myClassLoader))    
    )
    .start();
Or return a ClassLoader depending on the requested type:
EmbeddedStorageManager storage = EmbeddedStorage.Foundation(Paths.get("mydb"))
    .onConnectionFoundation(cf -> 
        cf.setClassLoaderProvider(typeName -> {
            if(typeName.startsWith("com.company.module1."))
            {
                return module1ClassLoader;
            }
            if(typeName.startsWith("com.company.module2."))
            {
                return module2ClassLoader;
            }
            return ClassLoader.getSystemClassLoader();
        })    
    )
    .start();
Class Loader in Application Server
Most application servers load the session's classes with the context class loader. Just use the one of the current thread:
EmbeddedStorageManager storage = EmbeddedStorage.Foundation(Paths.get("mydb"))
    .onConnectionFoundation(cf -> 
        cf.setClassLoaderProvider(ClassLoaderProvider.New(
            Thread.currentThread().getContextClassLoader()
        ))    
    )
    .start();
Custom Legacy Type Handler
Custom Storing Behavior
Last modified 1yr ago
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