Programmer Think

1. General 1.1 concept of reflection Reflection is the key to being regarded as a dynamic language. Reflection mechanism allows programs to obtain the internal information of any class with the help of Reflection API during execution, and can directly operate the internal properties and methods of any object. After loading the Class, an o ...

1, Generics Genericity is another widely used feature in Java. Genericity means that the parameter type is not fixed, that is, any data type can be used. It also has another name, that is, parametric type - that is, not only the data itself is a parameter, but also the data type can be specified as a parameter - class Interfaces or methods can ...

What is reflection? java reflection mechanism is to know all the properties and methods of any class in the running state; For any object, you can call any of its methods and properties; This kind of dynamically acquired information and the function of dynamically calling object methods are called the reflection mechanism of java language (the ...

This article mainly introduces the related contents of reflection optimization of mybatis. Let's understand how reflection optimization of mybatis is done and why reflection optimization is needed. It is based on version 3.4.6Knowledge pointsWhat is reflectionWhy should mybatis be optimizedHow is mybatis optimizedWhat is reflectionWhen it comes ...

Foreword: let's talk about reflection Codeword is not easy. Pay attention Reprint, please explain! Mind map:   catalogue What is reflection The following content will be explained around the Student class Class class Reflection instantiation Reflect dynamic method calls Reflection read / write properties                    Wh ...

catalogue 1, Annotation (also annotated) ■ comments and meta comments acting on the code: □ comments applied to the code: □ meta annotation (annotation applied to other annotations): □ highlight @ Retention and @ Target: ❀ important application of Annotation: using Annotation in reflection (1) Annotation on class name: (2) ...

Four methods to obtain Class instances Call the properties of the runtime classCall getClass() through the object of the runtime classCalling Class static method: the most commonly used method in forName(String classPath) developmentLoader using class: ClassLoader (just know) package day_12_29; import org.junit.Test; /** * @author ...

preface I often use the reflection mechanism in practical projects, so I will take some summary notes on the learned reflection usage for future replay. There is such a class: package com.example.demo; import com.alibaba.fastjson.annotation.JSONField; public class User { private String name; @Value( value ="age_a") private ...

0. Concept Reflection Library: a collection of tools that can be used to write programs that dynamically manipulate Java code. Reflection: a program that can analyze the ability of classes, which can be used to The ability to analyze classes at run time Check objects at run time Implementation of generic array operation code Using Method objec ...

Reflection (you also want to get the information in the class when the class is loaded) / / use the class in another way Normally, you need to load the class first, and then create an object call When we don't know the properties, methods, constructors and comments in the class, we also want to call the properties and methods in the class. We ...