Mimic

Mimicing is, indeed, kind of way to bypass java single inheritance paradigm. It allows to copy all declared fields, constructors and methods in a given class into another class.

Mutliple plugins can be used to trigger AfterBurner on maven and gradle :

• for gradle
• for maven

An imperative equivalent of Mimic is available on GitHub : AfterBurner.

Example usage

You can find a sample in our repo.

Let's say we got a class Example and its base class ExampleAncestor :

public class ExampleAncestor {

    public void doStuff() {
    }
}

@Mimic(sourceClass = ExampleTemplate.class,
	mimicMethods = {@MimicMethod(methodName="doOtherStuff",mode=MimicMode.AT_BEGINNING)}
)
public class Example extends ExampleAncestor {

    @Override
    public void doStuff() {
        super.doStuff();
    }

    public void doOtherStuff() {
    }
}

As you can see, without Mimic, this class would basically do nothing.

BUT, as we used the Mimic annotations, it will receive code from the following template :

public class ExampleTemplate {

    public ExampleTemplate() {
        System.out.println("Inside constructor");
    }

    public void doStuff() {
        System.out.println("Inside doStuff");
    }

    public void doOtherStuff() {
    	System.out.println("Inside doOtherStuff");
    }
}

This means that :

1. the constructor of Example will receive the code of the constructor of ExampleTemplate
2. the method doStuff of Example will receive the code of the method doStuff of ExampleTemplate, after its call to super.doStuff (default mimic mode for methods).
3. the method doOtherStuff of Example will receive the code of the method doOtherStuff of ExampleTemplate, at the beginning of its body.

The resulting Example class will print :

Inside constructor
Inside doStuff
Inside doOtherStuff

Mimicing constructors and fields

Currently mimic supports :

• copying the code of each constructor of the source class into all constructors of the target class.
• copying all fields of the source class to the target class. In case a field exists in both class, an exception will be thrown.
• there are multiple modes to copy methods. See MimicMode class.

Enable Mimic in maven builds

Simply add the following to your maven build :

	<dependencies>
		...
		<dependency>
			<groupId>com.github.stephanenicolas.mimic</groupId>
			<artifactId>mimic-annotations</artifactId>
			<version>${mimic-library.version}</version>
			<scope>provided</scope>			
		</dependency>
		...
	</dependencies>
	
	<build>
		<plugins>
      ...
			<plugin>
				<groupId>de.icongmbh.oss.maven.plugins</groupId>
				<artifactId>javassist-maven-plugin</artifactId>
				<version>${javassist-maven-plugin.version}</version>
				<configuration>
					<includeTestClasses>false</includeTestClasses>
					<transformerClasses>
						<transformerClass>
							<className>com.github.stephanenicolas.mimic.MimicProcessor</className>
						</transformerClass>
					</transformerClasses>
				</configuration>
				<executions>
					<execution>
						<phase>process-classes</phase>
						<goals>
							<goal>javassist</goal>
						</goals>
					</execution>
				</executions>
				<dependencies>
					<dependency>
						<groupId>com.github.stephanenicolas.mimic</groupId>
						<artifactId>mimic-library</artifactId>
						<version>${mimic-library.version}</version>
					</dependency>
				</dependencies>
			</plugin>
			...
			</plugins>
	</build>			

Mimic will not add any byte to your app, but it will cut down boiler plate.