org.springframework.instrument.classloading

## Class SimpleLoadTimeWeaver

- java.lang.Object
- - org.springframework.instrument.classloading.SimpleLoadTimeWeaver

- All Implemented Interfaces:
    LoadTimeWeaver

      public class SimpleLoadTimeWeaver
      extends Object
      implements LoadTimeWeaver

  `LoadTimeWeaver` that builds and exposes a `SimpleInstrumentableClassLoader`.

  Mainly intended for testing environments, where it is sufficient to perform all class transformation on a newly created `ClassLoader` instance.

  Since:
    2.0
  Author:
    Rod Johnson, Juergen Hoeller
  See Also:
    `getInstrumentableClassLoader()`, `SimpleInstrumentableClassLoader`, `ReflectiveLoadTimeWeaver`

- - ### Constructor Summary

    Constructors
    Constructor and Description
    `SimpleLoadTimeWeaver()` Create a new `SimpleLoadTimeWeaver` for the current context `ClassLoader`.
    `SimpleLoadTimeWeaver(SimpleInstrumentableClassLoader classLoader)` Create a new `SimpleLoadTimeWeaver` for the given `ClassLoader`.

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `addTransformer(ClassFileTransformer transformer)` Add a `ClassFileTransformer` to be applied by this `LoadTimeWeaver`.
    `ClassLoader` | `getInstrumentableClassLoader()` Return a `ClassLoader` that supports instrumentation through AspectJ-style load-time weaving based on user-defined `ClassFileTransformers`.
    `ClassLoader` | `getThrowawayClassLoader()` This implementation builds a `SimpleThrowawayClassLoader`.

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Constructor Detail

    - #### SimpleLoadTimeWeaver

          public SimpleLoadTimeWeaver()

      Create a new `SimpleLoadTimeWeaver` for the current context `ClassLoader`.
      See Also:
        `SimpleInstrumentableClassLoader`

    - #### SimpleLoadTimeWeaver

          public SimpleLoadTimeWeaver(SimpleInstrumentableClassLoader classLoader)

      Create a new `SimpleLoadTimeWeaver` for the given `ClassLoader`.
      Parameters:
        `classLoader` - the `ClassLoader` to build a simple instrumentable `ClassLoader` on top of

  - ### Method Detail

    - #### addTransformer

          public void addTransformer(ClassFileTransformer transformer)

      Description copied from interface: `LoadTimeWeaver`
      Add a `ClassFileTransformer` to be applied by this `LoadTimeWeaver`.
      Specified by:
        `addTransformer` in interface `LoadTimeWeaver`
      Parameters:
        `transformer` - the `ClassFileTransformer` to add

    - #### getInstrumentableClassLoader

          public ClassLoader getInstrumentableClassLoader()

      Description copied from interface: `LoadTimeWeaver`
      Return a `ClassLoader` that supports instrumentation through AspectJ-style load-time weaving based on user-defined `ClassFileTransformers`.

      May be the current `ClassLoader`, or a `ClassLoader` created by this `LoadTimeWeaver` instance.

      Specified by:
        `getInstrumentableClassLoader` in interface `LoadTimeWeaver`
      Returns:
        the `ClassLoader` which will expose instrumented classes according to the registered transformers

    - #### getThrowawayClassLoader

          public ClassLoader getThrowawayClassLoader()

      This implementation builds a `SimpleThrowawayClassLoader`.
      Specified by:
        `getThrowawayClassLoader` in interface `LoadTimeWeaver`
      Returns:
        a temporary throwaway `ClassLoader`; should return a new instance for each call, with no existing state