Conceptions

Traditional reflection can often lead to verbose code. For instance, setAccessible(true) is a kind of regular code snippet. In com.alioth4j.reflect library, I encapsulate the regular usage of reflection API to simplify the processes of object creation and method invocation.
Meanwhile, drawing inspiration from the Builder pattern, I reimagine the way to use reflection: method chaining. This approach enchances code readability and mainainability.

Step-by-Step Usage

Step 1: Instantiate

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new Reflect<MyClass>()
    .clazz(MyClass.class)
    .construct(Class<?>[] parameterTypes, Object[] parameterValues)

or

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new Reflect<MyClass>(MyClass.class, Class<?>[] constructorParameterTypes, Object[] constructorParameterValues)

or

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new Reflect<MyClass>(existingObject)

or

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new Reflect<MyClass>()
    .exist(existingObject)

Step 2: Invoke methods

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.set(String fieldName, Object fieldValue) | .set(Map<String/* fieldName */, Object/* fieldValue */> setterMap)
.invoke(String methodName, Class<?>[] parameterTypes, Object[] parameterValues)

Step 3: Get the instance

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.reflect()

An Usage Example

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MyClass myInstance = new Reflect<MyClass>()
                .clazz(MyClass.class)
                .construct(Class<?>[] parameterTypes, Object[] parameterValues)
                .set(String fieldName, Object fieldValue)
                .invoke(String methodName, Class<?>[] parameterTypes, Object[] parameterValues)
                .reflect();

Implementation

public class Reflect<I>

Generics

Use <I> to improve type safety.

Fields

Two fields:

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private Class<? extends I> clazz;
private I instance;

Constructors

Constructor is (part of) the instantiation step. Just fill in the fields.

Methods

• Encapsulate the reflection API inside.
• Return this object to support method chaining.

public class ReflectException

• Thrown when an exception occurs during the usage of com.alioth4j.reflect.Reflect
• It is an encapsulation of the reflection-related exceptions, providing an unified way to handle exceptions
• As reflection is an unsafe mechanism itself, the safety should be guaranteed by the user

Conclusion

With the elegance of the Builder pattern, this library offers developers a simpler and cleaner way to leverage reflection in Java applications.