Installing jdk8 environment and the first java program on day1

Install jdk8 Step 1: download the JDK installation package. Here we download the jdk8 version of the official website of orical. Note: please check accept when downloading. Unpack and decompress after downloading: tar zxvf jdk-8u162-linux-x64.tar.gz Put JDK under / usr/lib/jdk8 mv jdk1.8.0_131/ /usr/lib/jdk8 Modify environment variables ...

Posted by harris97 on Wed, 01 Apr 2020 17:40:18 -0700

Operation mode of Retrofit2 under Kotlin project

Add dependency: Establish entity class to obtain network return data Describe the interface of the network request get mode: Post mode: Action to initiate request: Reference blog: http://blog.csdn.net/carson_ho/article/details/73732076 GitHub address: https://github.com/yangtianfu2018/Retrofit2Project Code ...

Posted by skiingguru1611 on Wed, 01 Apr 2020 17:36:14 -0700

Java data access object pattern

Java design pattern - Data Access Object Pattern The data access object pattern or DAO pattern separates the data access API from advanced business services. DAO patterns typically have the following interfaces and classes. The data provider interface defines standard operations for model objects. The data access object c ...

Posted by spidie on Wed, 01 Apr 2020 17:21:34 -0700

Android reads the meta of each part

In the Android manifest.xml manifest file, we can sometimes see the following configuration content similar to the beginning of the < meta data... > element: <meta-data       android:name="com.google.android.maps.v2.API_KEY"       android:value="AIzaSyBhBFOgVQclaa8p1JJeqaZHiCo2nfiyBBo" />   <meta-data  ...

Posted by beginPHP on Wed, 01 Apr 2020 17:04:31 -0700

Seven notes of ssh integration combined with xml

1. In the previous pure xml mode, we have many configuration files. We can use annotation and xml to develop. In this way, our configuration files will be much less. At the same time, we can directly see the configuration in the class, so that we can quickly build a ssh integration project First of all, we should consider: what do we need to re ...

Posted by FraXTC on Wed, 01 Apr 2020 16:31:22 -0700

March 2018 - the 13th CCF certification - the second java version

The second question of the 13th CCF certification It means that there are several small balls on a line, each moving in a certain direction at the same speed Reverse after collision At most, there will be two small balls colliding at the same time. I won't talk about it if there's proof Ask the position of all the balls at a ...

Posted by betportal on Wed, 01 Apr 2020 16:23:11 -0700

Evolution of singleton model, four singleton models

Single example implementation I A very simple implementation public class Singleton { public static Singleton instance = new Singleton(); private Singleton() { System.out.println("Singleton is create"); } public static Singleton getSingleton() { return instance; } } One disadv ...

Posted by gudfry on Wed, 01 Apr 2020 14:49:57 -0700

Remember a packet scan error

For a long time, I was very distressed about the problem of unable to inject dependency. For similar problems, I made the following summary: 1. For distributed architecture If the prompt indicates that the dependency cannot be injected, consider which project is not referenced. For the war package, all references should be made, for example:   ...

Posted by shams on Wed, 01 Apr 2020 11:06:51 -0700

Authority verification based on Spring Boot

Preface: There is a part of background management system, which needs to divide the roles of users, and then restrict the access content according to the corresponding permissions of roles; or some portal sites, only special personnel can see the corresponding page information. These all need permission control.   Technical points: Spring ...

Posted by Louis-Platt on Wed, 01 Apr 2020 10:38:23 -0700

Simple use of memcached java client

Simple use of memcached java client Start Memcached server ./memcached -d -m10 -u root -l 192.168.1.106 -p 2222 -c 256 -P /tmp/memcached.pid -The d option is to start a Daemons -m is the amount of memory allocated to Memcache, in MB, here is 10MB -u is the user running Memcache, here is r oot -l is the IP address ...

Posted by parkej60 on Wed, 01 Apr 2020 10:24:20 -0700