javassist-maven-plugin

A javassist maven plugin designed to alter class files after compilation. By creating your own ClassTransformer you can remove/add/edit code from/to/in your classes and write them back or to a different location.

Extend ClassTransformer

protected boolean filterCtClass(CtClass candidateClass)

override this if you wish to filter some specific classes.

protected void applyTransformations(CtClass classToTransform) throws Exception

is where you do the actual work. Some operations are quite tricky in javassist.

protected void writeFile(CtClass candidateClass, String classPath) throws Exception

override this if you wish to save your class file at a different location.

Add the following to your pom.xml

<project ...> ...

<dependencies>
	...
	<dependency>
		<groupId>nl.topicus.plugins</groupId>
		<artifactId>javassist-maven-plugin-core</artifactId>
		<version>1.0-SNAPSHOT</version>
		<scope>provided</scope>
	</dependency>
</dependencies>

<build>
	<plugins>
		...
		<plugin>
			<groupId>nl.topicus.plugins</groupId>
			<artifactId>javassist-maven-plugin</artifactId>
			<version>1.0-SNAPSHOT</version>
			<configuration>
				<transformerClasses>
					<transformerClass>
						<className>com.example.HelloWorldTransformer</className>
						<properties>
							<property>
								<name>filterPackageName</name>
								<value>com.example.entities</value>
							</property>
						</properties>
					</transformerClass>
				</transformerClasses>
			</configuration>
			<executions>
				<execution>
					<phase>process-classes</phase>
					<goals>
						<goal>javassist</goal>
					</goals>
				</execution>
			</executions>
		</plugin>
	</plugins>
</build>