GUI for Java Learning

1. What is a GUI The full name of GUI is Graphical User Interface. Graphical interface or graphical user interface refers to the user interface of computer operation environment which is displayed graphically. GUI is easier for users to use than the command line interface used by earlier computers. The wide application of GUI is one of the ...

Posted on Mon, 06 Dec 2021 13:20:29 -0500 by snteran

mybatis source code interpretation II - full analysis of call process

Official documents Interpret according to the jdbc stage of preliminary preparation to configureSplicing sql statementsLoad the data source and get the ConnectionGet StatementExecute get resultsResult conversioncloseexception handling Example 1: com.dzq.MybatisSessionTest The most basic function, read the source code according to t ...

Posted on Wed, 01 Dec 2021 04:06:01 -0500 by unclebob

Java object oriented polymorphism

1. Interface When all methods in a class are abstract methods, we can define them as interfaces. An interface is also a reference data type, which is more abstract than an abstract class. There are two important meanings of the interface: Definition of rulesProgram scalability Interface definition format: public interface interface int ...

Posted on Mon, 22 Nov 2021 13:01:02 -0500 by work_it_work

Reflection, proxy mode

JavaSE advanced JUnit unit testing, reflection, annotation, dynamic proxy Chapter I Junit unit test 1.1 Junit concept Unit test refers to the test code written by programmers to verify the expected correctness of the methods in their own classes. Once the unit test has written these test codes, it can be used all the time and can realize au ...

Posted on Wed, 17 Nov 2021 01:07:22 -0500 by stlewis

java data type

  int type (4 bytes) (- 2 ^ 31 ~ 2 ^ 31-1) In java, one int byte accounts for 4 bytes, which is not directly related to the operating system (8 binary bits = 1 byte) System.out.println(Integer.MAX_VALUE);//Calculate the maximum and minimum of shaping respectively System.out.println(Integer.MIN_VALUE); If the result of the operation exceed ...

Posted on Thu, 11 Nov 2021 05:37:47 -0500 by Sulphy

[java basic syntax] explain generics in Java in detail

preface: The knowledge of generics is actually ahead Generic and wrapper classes in Java This chapter has introduced some, but those knowledge is to pave the way for the later introduction of Java collection framework. Today's chapter will fully introduce generics in Java together with the previous chapter! 1. Review of the previous ...

Posted on Wed, 10 Nov 2021 22:54:58 -0500 by electricshoe

[JavaSE] Lambda, Int and Integer

[JavaSE] Lambda, Int and Integer 1, Inner class and anonymous inner class ​ Internal classes are classes defined in classes. Their main function is to put logically related classes together. Anonymous inner class is a special inner class. It has no class name. When defining a class or implementing an interface, it generates an object of the c ...

Posted on Thu, 04 Nov 2021 03:06:16 -0400 by zzman

Detailed explanation of Java construction method / garbage collection mechanism / brief description of JVM tuning / memory leak

Construction method Constructors, also known as constructors, are used to create and initialize objects. Detailed explanation of construction method (need to master) Called through the new keyword. Although the constructor has a return value, the return value type cannot be customized (the return value type is this class), and return cannot ...

Posted on Wed, 03 Nov 2021 19:33:15 -0400 by Dang

[JavaSE series] Java classes and objects, all things are objects

⭐ ♪ previous words ⭐ ️ This article introduces you to Java classes and objects. I believe you have heard of object-oriented programming. Java is an object-oriented programming language. Different from C language, C language is a process oriented programming language. We can understand the difference between object-oriented and process-oriented ...

Posted on Wed, 03 Nov 2021 18:44:37 -0400 by redreset

Java - classes and objects

catalogue 1, Write in front 2, Preliminary cognition of class and object   3, Classes and instantiation of classes 1. Class 2. Class instantiation   4, Member of class 1. Field / attribute / member variable   2. Method 3. static keyword 4. Summary 5, Encapsulation   1. private implementation encapsulation 2. get ...

Posted on Tue, 02 Nov 2021 18:03:17 -0400 by deltawing