Programmer Think

Based on JDK 1.7 Inheritance and implementation methods public class ArrayList<E> extends AbstractList<E> implements List<E>, RandomAccess, Cloneable, java.io.Serializable { Let's look at the main methods add(E) to add elements /** * Appends the specified element to the end of this list. * * @param e e ...

The following operations are performed on the Aliyun server. The default yum source is Aliyun.If the default is not Aliyun or 163, it is recommended to modify it before yum operation. Modify yum source to Ali source Check if installed rpm -qa | grep java rpm -qa | grep jdk rpm -qa | grep gcj No output means no installation ...

No matter when you start, it's important not to stop after you start Three SqlSession s DefaultSqlSession and SqlSessionManager and SqlSessionTemplate are three common sqlsesion s I have From the class diagram, you can see that all three of them have implemented SqlSession, that is, they can all represent a session.Unlike others, SqlSessionM ...

I. overview This paper is based on JDK8 The underlying LinkedList is realized by the data structure of two-way collection Memory does not need continuous space guarantee Element search can only be sequential traversal search Better performance for add and delete operations LinkedList can be used as List, queue and stack. It supports adding an ...

1. First contact with websocket, spend more than a day looking for relevant materials, and refer to relevant examples on the network( https://www.cnblogs.com/qilin-3611/p/7054270.html )A simple front-end and back-end demo is arranged. The back-end demo directly uses the demo of the article in the link. After downloading, tomcat ...

  the previous section introduces the Java bytecode structure, and this section introduces the bytecode enhancement technology. Java bytecode enhancement refers to modifying and enhancing the function of Java bytecode after it is generated, which is equivalent to modifying the binary file of application program.   common bytecode enha ...

Preparation Install MongoDB jdk 1.8 maven 3.0 idea Environmental dependence Introduce spring boot starter data mongodb dependency in pom file: <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-mongodb</artifactId> </depen ...

I. Introduction public class Thread implements Runnable { /* Slightly ahead */ /* ThreadLocal values pertaining to this thread. This map is maintained * by the ThreadLocal class. */ ThreadLocal.ThreadLocalMap threadLocals = null; /* Slightly later */ } First of all, we see that there is a property threadLocals in Thread ...

1. First install the jave environment jdk Download address I use the latest version. Sometimes the version corresponds to elastic search 2. Install elastic search Download address 3. Install the Laravel scout full-text search package. Here I use version 5.0.3, Tamayo / Laravel scout elastic. The version here is very important, otherwise I will ...

1, background In Dubbo, many extensions are loaded through SPI mechanism, such as Protocol, Cluster, LoadBalance, etc. Sometimes, some extensions do not want to be loaded in the framework startup phase, but they want to be loaded according to the runtime parameters when the extension method is called. It sounds contradictory. If the extension i ...