QA Official

Spring IOC is slowly summing up.. 2019-04-10
1. Dependency Inversion Dependency inversion principle: Rely on abstraction, not on concreteness.Programming for interfaces, not for implementations.The level of abstraction includes the business logic of the application system and strategic decisions that are important to the whole system. It is the embodiment of inevitability and is relatively stable.While the specific level contains some minor implementation-related algorithms and logic, as well as tactical decisions, with considerable chance choices.Specific levels of code are subject to frequent changes.

ajax and the Essential Principle of jsonp with Padding's Cross-domain 2019-04-10
ajax Basic Concepts To understand this concept, one must first know synchronous interaction and asynchronous interaction. synchronous interaction: the client browser sends a request to the server, and the server returns a page. the returned page will overwrite the previous page. we call this interaction synchronous interaction asynchronous interaction: that is, the browser can be broken to send a request to the server, the server returns data, and the returned data will not overwrite the previous page.

arm neon instruction set 2019-04-10
arm neon instruction classification: normal instruction (q) 正常指令可对上述任意向量类型执行运算,并生成大小相同且类型通常与操作数向量相同的结果向量。 长指令(l) 长指令对双字向量操作数执

jsonp with Padding's Principle, Application Scenarios, Advantages and Disadvantages 2019-04-10
In the development test, cross-domain operations will inevitably be carried out under different domains. For security reasons, the same origin policy in the browser prevents scripts loaded from one domain from obtaining or operating. Document attributes under another domain, which need to be solved in a cross-domain way, such as using JSON with Padding, iFrame, etc. 1. Principle of JSON with Padding jsonp with Padding, namely json+padding, dynamically creates a script tag, and can obtain javascript, under any domain by using src attribute of the script tag.

(reprint) who should be responsible for the vicious expansion of rogue software? 2019-04-10
just saw a post on a BBS (XX community → introduction of new software), feel the same way and reprint it. Title: At present, the degree of hooliganism in rogue software is outrageous Similar to and, they jumped out of my maxthon every day and set it as an advertisement to filter. It was useless. Later, on the recommendation of Kanban friends, they used Huangshan to kill him.

Common Sorting Algorithms (2) (Select Sort) 2019-04-10
Related Articles: Common Sorting Algorithms (Zero) (Summary and Comparison of Various Sorting Algorithms) Common Sorting Algorithms (1) (Bubble Sort, Insert Sorting) Common Sorting Algorithms (2) (Select Sort) Common Sorting Algorithms (3) (Fast Sorting, Merge sort, Counting sort) Common Sorting Algorithms (4) (Radix sort, Bucket sort) Selection Sort Selection sorting is divided into three types: Straight Selection Sort, Tree Selection Sort (tournament sorting) and heapsort (max heap and Xiaogendui).Straight Selection Sort

Distributed Lock Principle and Implementation 2019-04-10
From: At present, almost many large websites and applications are deployed in a distributed way. The problem of data consistency in distributed scenarios has always been an important topic.The distributed CAP theory tells us that "no distributed system can satisfy Consistency, Availability and Partition tolerance at the same time, at most it can satisfy two at the same time."Therefore, many systems have to choose between the three at the

Firewall Series (II)-Packet Filtering, Firewall's Main Technology, State Detection Technology 2019-04-10
Firewall Series (II)-Main Technologies of Firewall Essential Knowledge: TCP/IP Basis Packet Filtering work object–> packetFirewall processes packets before they enter the systemThe Firewall module that implements Packet Filtering should be located at the network layer of the operating system protocol stack. Filter Objects filtering for IP View the packet header of each IP packet, compare the packet header data with the rule set, forward the packets allowed by the rule set, and reject the packets not allowed by the rule set

Firewall Series (III)-Agent Technology for Firewall's Main Technologies 2019-04-10
Firewall Series (III)-Main Technologies of Firewall Proxy Technology Proxy Technology Overview The Firewall of proxy technology runs between the internal network and the external network in the form of a proxy server, realizes the security control function at the application layer, and plays the role of transferring application services between the internal network and the external network. 1. Agent Execution Process (Two Cases) 1. The proxy server monitors the request

Firewall Technology (I) 2019-04-10
Firewall Technology (I) At present, effective measures to ensure network security mainly include: Firewall, identity authentication, encryption, digital signature and content check, etc. Firewall refers to the combination of a series of components arranged between different networks or network security domains.It is the only entrance and exit of information between different networks or network security domains. It can control (allow, deny and monitor) the flow of information into and out of the network according to the enterprise's security policies and has strong anti-attack capability.