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Spring4.x Learning Notes-Spring Concept, IOC Concept and Basic Usage 2019-04-04
1. Spring Framework Related Concepts Open Source Lightweight Framework Spring framework mainly involves two partsAOP: Aspect Oriented Programming (Optimization of Code Extension)IOC: Inversion of Control (Change in Object Creation Method) Spring is a one-stop framework, providing technical support in javaee three layers.Web layer (presentation layer): springMVCServive Layer (Business Logic Layer): IOC of springDao Layer (Data Access Layer): spring's jdbcTemplate 2. IOC Operation Basis of spring (Configuration File Method) 1, the

[JZOJ4816]label 2019-04-04
general idea of topic A tree of size nn, each node can be given an integer weight within [1,m][1,m].It is required that the absolute value of the weight difference between adjacent nodes is not less than kk. Find the number of schemes and modulo 109+710 9+7. TT group data for one test point. 1≤T≤10,1≤n,k≤102,m≤1091\le T\le 10,1\le n,k\le 10^2,m\le10^9 topic analysis An obvious method is to make fx,yf_{x,y} represent the number of schemes where the value of point xx takes yy.

[Spring] IOC Implementation Principle-Reflection and Factory Mode 2019-04-04
Reflection Mechanism ConceptLet's consider a scenario. If an object wants to view its own member properties while the program is running, what should we do?Consider another scenario. What if we want to obtain Class information of a class at runtime, such as its attributes, construction methods, and general methods before considering whether to create its objects?This requires reflection! We. java files will become. class files after compilation. This is like a mirror, itself is.

[spring Getting Started Learning Notes ][spring IoC Principles] 2019-04-04
What is IoC Inversion of Control (abbreviated as IoC) is a design principle in object-oriented programming, which can be used to reduce the degree of coupling between computer codes.One of the most common methods is called Dependency Injection (DI) and another is called Dependency Lookup.Through Inversion of Control, when an object is created, an external entity that regulates all objects in the system passes the references of the objects it depends on to it.

pca and ica Learning and Understanding 2019-04-04
This article is a summary of mathematics and principles after learning. pca readings from Principal Component Analysis (PCA) Recently, I reviewed linear regression and explained the relationship between the two variables in the probability book. Are there any relationships between variables X and Y?Of course, in the book, x is a variable, y is a random variable, and y is assumed to obey the positive distribution.Then assuming that they are linearly related, their relationship must be y = ax+b.

word2vec usage process (Java version) 2019-04-04
here only introduces how to use, not the principle (want to know the principle of see here) 1. download Word2Vec(Java version address) 2. Prepare a corpus according to your own situation (sogou 2012 News Data) 3. Processing corpus. Take sogou 2012 News Data for Example; (1) firstly, HTML tags are processed and converted to utf8 encoding format: catnews _ tensite _ XML.dat | iconv-fgb18030-ttf-8-c | grep " < content >"

1. IOC, one of Spring2 cores 2019-04-04
1. IOC, one of Spring2 cores 1. Introduction and Function of spring Spring is an open source design framework, which solves the loose coupling problem between business logic layer and other layers. Therefore, it applies interface-oriented programming ideas throughout the entire system.Spring is a lightweight Java development framework that emerged in 2003 and was created by Rod Johnson.Simply put, Spring is a layered Java Platform, Standard Edition/Ee Full-Stack (one-stop) lightweight

Basic Concepts of IoC in Spring (1) 2019-04-04
What is IoCIn the development of practical applications, it is necessary to avoid and reduce the dependency relationship between objects as much as possible, that is, to reduce the coupling degree.Ioc, on the other hand, solves various dependency relationships between general business objects and between business objects and persistence layer.In the implementation without Ioc, the objects are controlled by the internal code of the program.When an object needs to depend on another object, use new to create its dependent object to realize the connection between the two components, and this S implementation will cause the coupling between the components.

Bean&amp;#x27;s perception of IOC container 2019-04-04
Beans managed by a container generally do not need to know the state of the container and directly use the Bean, but in some cases, it is necessary to directly operate the IOC container in the Bean. At this time, it is necessary to set the perception of the container in the Bean.Spring IOC also provides this function, which is accomplished through a specific aware interface.Aware interfaces include the following:

Concise Discussion on the Benefits of Spring IOC 2019-04-04
Concise Discussion on the Benefits of Spring IOC   IOC: Inversion of Control, it is not a technology, it is a design pattern.The so-called Inversion of Control is the relationship between programs controlled by the container, instead of being directly controlled by the programming code in the traditional implementation.To put it bluntly, the container controls the dependency between objects. DI:Dependency Injection depends on injection, that is, the dependency relationship between components (objects) is determined by the container during runtime.