Programmer Group

1, Introduction to Comparable Comparable is a sort interface. If a class implements the comparable interface, it means that the class supports sorting. The list or array of objects of classes that implement the comparable interface can be automatically sorted through Collections.sort or Arrays.sort. In addition, the object implementing this i ...

Chapter 6 data type conversion Author: Zhang Zimo Java programs require that the data involved in calculation must be consistent in data types. If the data types are inconsistent, type conversion will occur. 1, Automatic conversion What data type will result from the addition of an int variable and a byte variable?  int i = 1;  byte b = 2; ...

catalogue 1, Overview of arrays 2, Array declaration creation 3, Array usage 4, Multidimensional array 5, Arrays tool class 6, Sparse array (Extended) 1, Overview of arrays ◆ an array is an ordered collection of data of the same type ◆ array describes several data of the same type, which are arranged and combined in a certain order. ...

abnormal Concept: an unexpected condition that occurs during program operation, rather than a compilation error. 1 Classification of anomalies For example:1. Throwable: The parent class of all exceptions. 2. Error: Throwable Subclass, indicating error, JVM collapse,Hardware problems or operating system related problems;Features: can not be a ...

Expiration: Secrets of JAVA Training Chapter 1: Pain Secrets of JAVA Training Chapter II: Gradually Magic Secrets of JAVA Training Chapter III: Jedi Strike Back Secrets of JAVA Training Chapter IV: Closed-door Training Secrets of JAVA Training Chapter V: "Wage and Gallbladder" Secrets of JAVA Training Chapter VI: Battle JAVA Refinemen ...

1, Encapsulation 1.1 package overview 1. Why encapsulation? If I want to use the washing machine, I just need to press the switch and washing mode. Is it necessary to understand the internal structure of the washing machine? Is it necessary to touch the motor?The computer we use has CPU, hard disk, keyboard, mouse, etc. each part works toget ...

1. Method concept and use 1.1 what is a method Method is a code fragment, similar to the "function" in C language. Function of the method: 1. It is a modular organization code (when the code scale is complex). 2. Make sure that the code is reused, and one code can be used in multiple locations. 3. Make the code better understo ...