/*
 * Copyright 2002-2012 the original author or authors.
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 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
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 *      https://www.apache.org/licenses/LICENSE-2.0
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 * Unless required by applicable law or agreed to in writing, software
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package org.springframework.instrument.classloading;

import java.lang.instrument.ClassFileTransformer;

Defines the contract for adding one or more ClassFileTransformers to a ClassLoader.

Implementations may operate on the current context ClassLoader or expose their own instrumentable ClassLoader.

Author:Rod Johnson, Costin Leau
See Also:
Since:2.0
/** * Defines the contract for adding one or more * {@link ClassFileTransformer ClassFileTransformers} to a {@link ClassLoader}. * * <p>Implementations may operate on the current context {@code ClassLoader} * or expose their own instrumentable {@code ClassLoader}. * * @author Rod Johnson * @author Costin Leau * @since 2.0 * @see java.lang.instrument.ClassFileTransformer */
public interface LoadTimeWeaver {
Add a ClassFileTransformer to be applied by this LoadTimeWeaver.
Params:
  • transformer – the ClassFileTransformer to add
/** * Add a {@code ClassFileTransformer} to be applied by this * {@code LoadTimeWeaver}. * @param transformer the {@code ClassFileTransformer} to add */
void addTransformer(ClassFileTransformer transformer);
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.

Returns:the ClassLoader which will expose instrumented classes according to the registered transformers
/** * Return a {@code ClassLoader} that supports instrumentation * through AspectJ-style load-time weaving based on user-defined * {@link ClassFileTransformer ClassFileTransformers}. * <p>May be the current {@code ClassLoader}, or a {@code ClassLoader} * created by this {@link LoadTimeWeaver} instance. * @return the {@code ClassLoader} which will expose * instrumented classes according to the registered transformers */
ClassLoader getInstrumentableClassLoader();
Return a throwaway ClassLoader, enabling classes to be loaded and inspected without affecting the parent ClassLoader.

Should not return the same instance of the ClassLoader returned from an invocation of getInstrumentableClassLoader().

Returns:a temporary throwaway ClassLoader; should return a new instance for each call, with no existing state
/** * Return a throwaway {@code ClassLoader}, enabling classes to be * loaded and inspected without affecting the parent {@code ClassLoader}. * <p>Should <i>not</i> return the same instance of the {@link ClassLoader} * returned from an invocation of {@link #getInstrumentableClassLoader()}. * @return a temporary throwaway {@code ClassLoader}; should return * a new instance for each call, with no existing state */
ClassLoader getThrowawayClassLoader(); }