Java

1.jvm:java the abbreviation for Virtual machine (Java vm).It is a fictitious computer, it is realized by simulating various computer functions on the actual computer.a very important feature of the Java language is its independence from the platform.

First, class loading mechanismThe classloader reads the binary data from the class's. class file into memory, places it in the method area, and then creates a Java.lang.Class object in the heap that encapsulates the data structure of the class

In the development of Java server-side code, we will encounter the external parameters of the validity of validation, and Hibernate-validator provides some common parameter check annotations, we can use.The hibernate-validator corresponding jar is

ObjectiveIn the previous article, we reviewed the basic Java data types, and this article reviews some of the modifiers in Java and string.Modifier descriptionJava modifiers fall into two main categories: Access modifiers Non-access

Back up data in tabular form(1) Import the POI jar packagePut under Lib: webroot\web-inf\lib\Poi-3.2-final-20081019.jar(2) StringBuffer converted to a two-dimensional arrayDefine a stringbuffer to \ r \ n A one-dimensional array with \ t divided

First, what is Jconsole?JConsole has been introduced from Java 5. JConsole is a built-in Java Performance Analyzer that can be run from the command line or in the GUI shell. You can easily monitor Java application performance and track code in Java

1. Java stream is divided into two kinds(1) Byte stream: can be used to read and write binary files and any type of file(2) Character stream: can be used to read and write text files, cannot manipulate binary filesStream of Byte stream

Writing the correct concurrency program requires proper management when accessing a mutable state.        It said earlier how to prevent multiple threads from accessing the same data at the same time by synchronizing, this chapter describes how to

JDK and JRE Concepts Jdk:java Development Kit Java Development Kit. The JDK is available to Java developers and includes Java development tools, as well as the JRE Jre:java Runtime Environment Java Runtime environment. including Java

Delayqueue, a thread-safe queue with deferred elements that returns an element that reaches the earliest delay time when non-blocking fetches an element from the queue, or empty (no element reaches the delay time). The generic parameters of the

Analysis of Distributed Lock implementation in Redis (2), analysis of redis Abstract: In the previous article, we mentioned three popular solutions for implementing distributed locks: database, Redis, and Zookeeper. This article mainly describes the

Java: Exception Handling, java Exception HandlingContent: Exception description Exception Handling Assertions     Start Date:Exception: An exception is an error that occurs during the running of the program. A common example is "Division by

Netty is a simple example of communication between the client and the server. Netty is based on NIO, and Netty provides high-level abstraction on NIO. In Netty, the Accept connection can be processed by a separate thread pool, and read/write

Small thread example -- control output, thread example --Small thread example -- control output Function: A small form with two buttons. Click start to start printing on the console. Click Stop to stop printing on the console. Import java. awt.

What does the volatile keyword in Java mean? How to use it ?, Volatile keywords Once a concurrent shared variable (class member variable, static member variable) being modified by the volatile keyword gives visibility (that is, the value of a

Notes-Virtual Machine (VM) installation, virtual machine vm A. Install CentOS7 in VMware14: Http://baijiahao.baidu.com? Id = 1583951426846264443 & wfr = spider & for = pc Note: B.Vmware workstation14 permanent key

Detailed description of DecimalFormat rounding in java, DecimalFormat is a subclass of NumberFormat used to format decimal numbers. It supports different types of numbers, including INTEGER (123), fixed point (123.4), Scientific notation (1.23E4),

JVM tuning series: garbage collection and jvm Tuning   Summary: jvm is a required series, which summarizes some common jvm collection mechanisms for easy reference. Before optimization, we must understand how it runs. java's Garbage Collection is

A deep understanding of Spring's transaction Propagation Behavior and a deep understanding of spring transactions Preface Spring defines seven types of transaction propagation behaviors in the TransactionDefinition interface. Transaction Propagation

Spring Boot uses the Allatori code obfuscation method, springallatori Allatori obfuscation Technology Allatori is a Java obfuscator, which belongs to the second generation, so it can protect your intellectual property rights in an all-round way.