guru99 java

Basic concepts of Java (1) What is Java and java?What is JavaJava? A development language (core feature: cross-platform, object-oriented, the name is here: what does 2 in J2EE mean). For developers, Java is basically equal to Jdk. Jdk version introduction here: Java develope

Java. Lang. virtualmachineerror Virtual Machine error. Indicates that the virtual machine is damaged or the resources required to continue the operation are insufficient. Java. Lang. arithmeticexception Arithmetic condition exception. For example, integer division by zero. Java. Lang. arrayindexoutofboundsexception An error occurred while exiting the array index.

Review of java basics-Java data types, review of java Data Types 1. java data type. 8 Basic Types and 3 reference types Basic type (also called original type): byte, short, int, long, char, float, double, boolean Reference Type: Class, interface, array 2. Basic java Data Typ

Welcome to other blogs on this topic: Deep Dive into Java Virtual Machine (I)-detailed explanation of the underlying structure of Java Virtual Machine Deep Dive into Java Virtual Machine (II)-class lifecycle (I) class loading and Connection In-depth Java Virtual Machine (III)-class lifecycle (ii) class initialization

foundation is solid to have a higher breakthrough. Just want Masons silently for themselves, for the family for the future lay the groundwork.As you can see, string is a class that does not need to create a new object using new. It is immutable (Constant), and its value (like "ABC" is created, cannot be changed). Naturally, string actually implements the function of the sequence of the basic type char, so the Chinese name "string". Here it is possible to doubt that Mason will find the JDK sourc

silently for themselves, for the family for the future lay the groundwork.As you can see, string is a class that does not need to create a new object using new. It is immutable (Constant), and its value (like "ABC" is created, cannot be changed). Naturally, string actually implements the function of the sequence of the basic type char, so the Chinese name "string". Here it is possible to doubt that Mason will find the JDK source code evidence to show you:This code is from the JDK1.7 source, the

This article describes Java SE, Java EE, Java I made the difference and shared some of the author's achievements. Currently, Java platforms can be divided into three versions based on software developers, service providers, and equipment manufacturers. Se, Java EE, and

Java-8 most popular images for understanding the Java mechanism and 8 images for Java The world is always better than ten million words! The following eight figures are from the Java tutorial of Program Creek. Currently, this is the most popular article on this website.I hope this article will help you review the knowl

A figure shows the Java Collection classes (summary of the Java Collection classes) and the java There are a lot of articles about Java Collection classes, but I recently saw a very interesting image, basically showing the overall framework of Java collections, which is very

Dark Horse programmer _ Java exception common Java Library Class, dark horse _ javaJava exception 1: Basic concepts of exceptions Exceptions are a type of command flow that causes program interruption. They are abnormal during runtime. in Java, all exceptions follow the object-oriented design philosophy, all exceptions exist in the form of objects and classes.2.

Why learn Java1. Arrangements2. LifeBasic data types and arrays1. The name of the identifier should have a rule, so it's called a naming convention. 1. A standard English name 2. Package Lowercase 3. class first uppercase 4. Constant all uppercase 5. Variable first letter lowercase, followed by the first letter of the word2.unicode Character Set65,536 characters The first 128 ASCII code corresponds to the Java language using the Unicode standard chara

Java Note: Part 4: Java program first run; Part 4: java # Daily nagging # This blog won't be published on time, because Xiaoxing has something to do today. However, I was eager to hear from fans, so I stayed up late last night. Thanks to xiaoxinghahahao (for example, I have to finish my Java notes like watching TV seri

JAVA Virtual Machine installation and JAVA environment configuration, JAVA virtual machine environment Configuration I recently helped others install the Java Virtual Machine. After the installation, problems have been solved for a long time. So I would like to share my experience with you. First, if

Java experiment 10-java database programming, 10-java Database Programming Purpose: 1) understand the composition and structure of JDBC 2) master the connection technology between Java programs and databases 3) Master how to use the DriverManager class, Connection, Statement, and ResultSet classes provided in the

Java Learning Series (21) Java object-oriented explanation, java object-oriented Reprinted please indicate the source: http://blog.csdn.net/lhy_ycu/article/details/45295947 I. Preface Annotation in Java is used in many aspects, such as @ Test, Spring, SpringMVC, and other frameworks in unit tests.

JAVA Learning (III): Basic Java syntax (conversion of variables, constants, data types, operators and data types), java OperatorsBasic Java syntax (conversion of variables, constants, data types, operators, and data types) 1. Variables In Java, you can declare variables by

The Java heap is the closest memory space for Java applications. Almost all objects are present in the heap. Java heap completely self-active management, through the garbage collection mechanism, the garbage object will voluntarily clean up. No explicit release is required. Depending on the Java garbage collection mec

[Java tutorial 04] basic Java syntax, 04 java In the previous article, we ran a simple java program, but did not explain the content and meaning of the Code. Learning, we need to know it, but to know it, so this article will explain the basic syntax of the java program. Afte

Java virtual machine architecture, Java Virtual MachineLifecycle of a Java Virtual Machine A running java VM instance is responsible for running a java program. When a Java program is started, a virtual machine instance is born. W

Java 7: Reading Notes on core technologies and best practices-java source code and byte code operations, java 7 Best Practices General process: developers write the java source code (. java)-> javac (compiler)-> java byte code (.