行为型模式

The template-method pattern applies when the overall algorithm steps are fixed while some parts vary, with Java and Go implementations and a combined template/factory/strategy example.

The state pattern selects different processing logic according to the current state, with Java and Go examples.

The strategy pattern selects one of several algorithms for accomplishing the same task according to a type or context, with Java and Go examples.

The observer pattern broadcasts state changes from a subject to observers, with Java, Go, and application examples.

The chain-of-responsibility pattern links handlers that can process the same type of request, with Java, Go, and filter-chain examples.

Mediator-pattern notes with UML, a Java department example, and a Go computer-component example.

Command-pattern notes with a Java Course example, command objects, and a command invoker.

Memento-pattern notes showing how to save an object's state and restore it later.

A minimal original note for the interpreter design pattern.

Visitor-pattern notes separating data structures from operations, with a Java course example.

Iterator-pattern notes showing Java and Go implementations for traversing aggregate objects.