java power of 2

Seventh: " exceptions, assertions and logs " Summary of Knowledge pointsthis week, we learned about exception handling in Java, and here are some of the gains. I. The difference between an unchecked exception and a checked exception:unchecked Exception handling method: 1, capture 2, continue to throw 3, do not handle. checked Exception handling methods: 1, continue to throw, negative methods, can always be

Java Data Structure series-stack (2): Stack chain storage structure and its operations, java Data Structure Package Stack; import LinkList. singlyLinkList; public class LinkListStack {private SinglyLinkList

JAVA thread Learning (2), java thread LearningThis is a project with three classes.First:Package com;// Military thread// Simulate actions of both sidesPublic class ArmyRunnable implements Runnable {// Volatile ensures that the thread can correctly read the value written by other threads// VisibilityVolatile boolean keepRunning = true;@ OverridePublic void run ()

Generic programming means that the code you write can be reused by many different types of objects.Upper bound of generic variable: the upper bound declared by the extends keyword can be either a class or an interface.Generic variable lower bound: the type of a generic parameter that is fixed by the keyword super is a type or other superclass. When a generic variable is declared so, when a generic type is instantiated, it needs to be explicitly typed as the specified upper-bound type or its subc

the commonly used IO operations in Java can be divided into four parts: file class operation, Randomaccessfile class operation, Byte stream operation, character stream operation. as long as you master all the examples listed in this article, basically for the Java IO Stream operation can be said to be mastered. The following are examples of the operations that are commonly used in the four parts, in the fo

debugging tool 4: Constant (Master) (1) The amount of the value does not change during program execution (2) Classification: A: Literal constants B: Custom Constants (later) (3) Literal constants A: string constant "Hello" B: integer constant 12,23 C: decimal constant 12.345 D: Character constant ' a ', ' a ', ' 0 ' E: Boolean constant True,false F: Empty constant Null (said later) (4) provides four representations of integer constants in

Java BASICS (7) Object-oriented (2), java basics object-oriented Here are some of the knowledge points and code I summarized in my previous class. Most of the notes I think are very good and classic, sincerely hope that these will help those who want to learn! It is inconvenient to upload code by module. There are also many things, and they are also clear! If you

JAVA notes: Java Network Programming (2) URL and URLConnection, The full name of a URL is Uniform Resource Locator, which is a unified Resource Locator and can be used directly to find resources on the Internet. URLConnection is a class that encapsulates methods used to access remote network resources. It can be used to establish connections with remote servers a

JAVA 19th (java program exception handling (2 )) Capture of exception handling: This is a targeted way to handle exceptions. 6. try and catch Specific format: Try {// code to be checked for exceptions} catch (exception variables) // The amount of changes is used to accept objects with exceptions {// code for handling exceptions} finally {// code that will be e

Java Algorithm instance set (2), java Algorithm instance set This is a private possession of a computer teacher in Standford, which contains a lot of Java/C ++ algorithm implementation code. If you are interested, you can check it out. I have been learning Java for almost

Java Learning Chapter SixthThis week we learned about interfaces in Java, lambda expressions, and inner classes, and here are some of the things I Learned:1. Interface:Comparable x = new comparable (...); ERRORComparable x= new Employee (...); Ok(2) You can use instanceof to check whether an object implements an interface.if (AnObject instanceof comparable){ ....

Java programming ideology note (2) -- initialization and java programming ideology I. Problems With the development of the computer revolution, the "insecure" programming method has gradually become one of the main reasons for the high cost of programming. Initialization and cleanup are two security issues. Ii. java So

1. ConceptThe Java reflection mechanism is in the running state, for any class, can know all the properties and methods of this class, for any one object, can call any of its methods and properties; This dynamically acquired information and the ability to dynamically invoke the object's methods are called the reflection mechanisms of the Java language.2. Get the

JAVA class and object (2) ---- class definition basics, java ---- Classes are the basic elements of java programs and an important composite data type in java. It encapsulates the states and methods of a class of objects, and is the prototype of this class of objects. The im

Java. util package (2) -- Connection interface, java. util. localeConnection interface Introduction The Connection interface is the root interface of the java set and has no implementation class. It only contains sub-interfaces and various containers that implement sub-interfaces. It is mainly used to represent the abs

Java third week learning experience NBSP;NBSP;NBSP;NBSP;NBSP;NBSP;NBSP;NBSP;NBSP;NBSP;NBSP; Through this week's learning, I learned the core of Java, understood the definition of user-defined class, understood the declaration of objects, understood the use of constructors to initialize objects, used class properties and methods, and understood the purpose of the package and import statements. You know, as

pressure of the programmer to compile the program, use it well, you can make your program concise and clear.This week, the teacher led us to learn this chapter, while learning concepts, while practical examples, such a learning method I like, feel receptive to knowledge than blindly look at the concept of obscure faster and easier. But always feel a bit of difficulty in bridging the knowledge, this is what I owed in front of the account, some knowledge points smattering, and not in time to fill

A simple example1 Public void Testnum () {2 System.out.println (Math.Round (12.5)); 3 System.out.println (Math.Round ( -12.5)); 4 }56 output:137 -12The output is determined by theThe rounding rules of the math.round affect.TwoRounding method in Java 1.round_up: Rounding away from 0 directions. Rounding in the direction of the absolute maximum, as long as the bit is d

Download related source code:Java. util. ArrayListJava. util. AbstractListJava. util. ListArrayList is a variable-length array implementation of the List interface. All List operations are implemented and null values can be stored. Except for not synchronizing data, ArrayList is basically equivalent to Vector. Almost all methods are synchronized in the Vector, but the ArrayList only synchronizes writeObject and readObject. Other methods such as add (Object) and remove (int) are not synchronized.

(i) Inheritance in Java:　　 About inheritance, in Java class inheritance can only be single inheritance, not as flexible as c+++, can inherit more, the consequence of multiple inheritance is a variety of relationship chaos, equivalent to a child has 2 mother, social relations complex, not conducive to the development and maintenance of the late stages of the progr