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2024-09-24-TIL

Posted
By August
1 min read

2024-09-24-TIL

Today I Learned

Spring MVC Request Life Cycle

Java 23

…

Java Proxy

Proxy provides static methods for creating dynamic proxy classes and instances, and it is also the superclass of all dynamic proxy classes created by those methods.

To create a proxy for some interface Foo:

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     InvocationHandler handler = new MyInvocationHandler(...);
     Class<?> proxyClass = Proxy.getProxyClass(Foo.class.getClassLoader(), Foo.class);
     Foo f = (Foo) proxyClass.getConstructor(InvocationHandler.class).
                     newInstance(handler);

or more simply:

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     Foo f = (Foo) Proxy.newProxyInstance(Foo.class.getClassLoader(),
                                          new Class<?>[] { Foo.class },
                                          handler);

A dynamic proxy class (simply referred to as a proxy class below) is a class that implements a list of interfaces specified at runtime when the class is created, with behavior as described below. A proxy interface is such an interface that is implemented by a proxy class. A proxy instance is an instance of a proxy class. Each proxy instance has an associated invocation handler object, which implements the interface InvocationHandler. A method invocation on a proxy instance through one of its proxy interfaces will be dispatched to the invoke method of the instance’s invocation handler, passing the proxy instance, a java.lang.reflect.Method object identifying the method that was invoked, and an array of type Object containing the arguments. The invocation handler processes the encoded method invocation as appropriate and the result that it returns will be returned as the result of the method invocation on the proxy instance.

Java Reflection

JDK CGLIB

TIL, 2024-TIL
TIL Reverse Proxy
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