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Chapter I Stream flow 1.1 INTRODUCTION (1) Multi step traversal code of traditional collection Almost all collections (such as Collection interface or Map interface) support direct or indirect traversal operations. When we need to operate on the elements in the Collection, in addition to the necessary addition, deletion and acquisitio ...

Algorithm efficiency There are two kinds of algorithm efficiency analysis: Time efficiency,Space efficiency. Time efficiency - > time complexity Space efficiency - > space complexity. Time complexity mainly measures the running speed of an algorithm, while space complexity mainly measures the additional space required by an algorithm I ...

1. Concept of Java Io flow Stream: represents any data source object capable of producing data or receiving end object capable of receiving data. The essence of flow: data transmission. According to the characteristics of data transmission, the flow is abstracted into various types to facilitate more intuitive data operation. Function: ...

⭐ ♪ previous words ⭐ ️ This article introduces you to the basic knowledge of Java - composition, polymorphism and interface, friends, long time no see, question A left to readers in the previous blog post package and inheritance. This article will introduce polymorphism and interfaces in detail. The inheritance introduced last time is the ba ...

introduction The. properties file in Java is a configuration file, which is mainly used to express configuration information; Generally speaking, the stored data is like the corresponding relationship between key and value in Map; In this way, attributes can be matched through key value pairs, and each key and its corresponding value in the at ...

1, What is a class loader class loader: responsible for loading. class files (stored physical files) into memory Class loading time:         1. Create an instance (object) of the class         2. Call the method of the class         3. Access class variables of classes or inter ...

Foreword: in the last article, we learned the sequence table and found that we have a certain grasp of the concept of the sequence table, but after learning the sequence table, we found that there are some places that we can't do better or difficult to do, so we have a linked list. This article will take you into the study of the linked list! ...

catalogue ✨ Write in front ✨ Initial knowledge of Java and development environment installation 🙌 Java Language Overview 🎆 What is the Java language 🎆 Master Java 🎆 Why Java 🙌 Is Java the best language 🙌 Installation of development environment 🎆 JDK installation 🎆 Installation of IEDA ✨ Data types and operators 🙌 Variabl ...

reflex 1. Class loader 1.1 loading of class When a program wants to use a class, if the class has not been loaded into memory, the system will initialize the class through three steps: loading, connecting and initialization. load This is to read the class file into memory and create a class object for it. When any Class is used, the sy ...

Overview of JDBC JDBC (Java Database Connectivity) is a set of interface to connect database provided by Java language. The implementation of interface is called database driver in JDBC and is provided by major database manufacturers. The reason for this is that the user doesn't need to care about how the underlying implementation is imple ...