Java

"This week began the evening 10 o'clock back to the bedroom after running, come back to take a bath after you do not want to read, plus their lazy, just a few days not updated ... The sins of sin, from this day onwards must continue to insist

String strings are read-only, immutableTo view the source code of the string class, you can find that the string class is decorated with the final keyword;In addition, you can also see the string class source code in other ways to implement, any can

We can usually set the margin directly in XML, such as:However, in some cases, it is necessary to write in Java code, but the view itself does not have a setmargin method, how to do?By looking at the Android API, we found that Android.view.ViewGroup.

I believe that all of you are very familiar with the basic data types, such as int, float, double, Boolean, Char, and so on. Basic data types do not have the properties of the object, such as the basic type cannot invoke the method, the function is

One, inheritWhen some classes have some common content, these common elements can be extracted into the parent class.1. Analysis of properties and methods common to multiple classes2. Extract a parent class from the common, create a parent class,

One, the objectObject: An objective thing is an object.Object contains: attributes (Features) and methods (actions)Two, classClass: A collection of groups of objects that have the same properties and methods.The relationship between classes and

Referenced from: http://blog.sina.com.cn/s/blog_6d6f5d7d0100s9nu.htmlOften see the use of the recordset in the program, commonly used are collection, HashMap, HashSet, ArrayList, because it is not clear the relationship between them, so in use often

Static represents the meaning of "global" or "static", which modifies member variables and member methods, and can also form statically static blocks of code that are independent of any object of that class by static decorated member variables and

Vo is a mapping to a table in a database, and a table corresponds to a VODAO is to use VO to access the real table, the operation of the database is done in DAOBo is the business layer that does the logical processingVO, PO, BO, QO, DAO, POJO,The

The Hashcode method returns the hash code value of the object.The Hashcode () method can be used to improve the efficiency of the search in the map, map will be based on different hashcode () in different locations, map in the search for an object

Author: Jakob Jenkov Translator: Li Jing ([email protected])This section briefly summarizes the Pushbackinputstream,sequenceinputstream and PrintStream in Java IO. Among them, the most common is printstream,system.out and System.err are printstream

Lock is an interface that provides unconditional, polling, timed, and interruptible lock-fetching operations, all of which are explicitly locked and unlocked.The package path is: Java.util.concurrent.locks.LockThe core method is lock (), Unlock (),

Goal1, Block2. GC (Learn)3. Package Import4. EncapsulationOne, block{} classification1, ordinary blockfunction: Organize code, solve the scope of variables, save memory.A variable with the same name cannot be declared within the same scope.2. Static

First, Java program operating mechanismPrograms written in the Java language need to be compiled to generate platform-independent bytecode (. class files ).This bytecode must use the Java Interpreter (JVM) to interpret execution.The JVM is a virtual

In the Java garbage collection algorithm in front of the garbage collection algorithm in the generational collector, today saw a video found inside will also very good, so decided to summarize.We know that in the generational collection algorithm

http://gimgen1026.iteye.com/blog/152023The Properties class is no longer new, it has been in early Java programming and almost nothing has changed. The Tiger version of J2SE enhances this class by specifying multiple key-value pairs separated by an

In windows, nginx + tomcat group + redis realize session sharing, nginxredis     In this example Nginx 1.9.13 Tomcat 7.0.64 Apsaradb hybriddb for redis 2.8   Procedure: ① Prepare two tomcat servers, modify the port, and modify the index. jsp content

Use Retrofit in combination with RxJava instructions PS: I haven't updated my blog after years. It's so busy. Today, Saturday finally took time out and decided to write an article about using Retrofit with RxJava. It is also useful for the projects

Java Abstract class, java Abstract Not to mention, let's start with a code segment. Public class Abstract {public static void main (String [] args) {cl2 c = new cl2 (); c. method () ;}} abstract class Abc {public abstract void method ();} class cl2

Install jdk For Windows and jdk For Windows 1. Download JDKView latest: http://www.oracle.com/technetwork/java/javase/downloads/index.htmlSelect the appropriate JDK for download Based on the Operating System2. Run the JDK Installer3. Select the