ARCUsed in conjunction with non ARC in a project.
1，Select the Targets in the project and select the Target you want to operate.2，Select Build Phases, double-click the file that requires ARC in Complie Sources, and enter: – fobjc – arc in the input box, and – fno – objc – arc if you don’t want ARC
There is no problem with mixing. It doesn’t matter if ARC code continues to insist on who will apply for release. Previous libraries did not have time to rewrite.
And I don’t know what third-party code you’re using. Generally speaking, there...
802.11b/gOr 802.11b/g/n generally supports 13 channels.
Channel is also called channel, frequency band, is a wireless signal (electromagnetic wave) as the transmission carrier of data signal transmission channel. Wireless networks (routers, AP hotspots, and computer wireless network cards) can run on multiple channels. All kinds of wireless network devices should be completed within the coverage of wireless signals.We use different channels to avoid interference between signals. Channel partition of 2.4GHz (=2400MHz) frequency band. There are actually 14 channels (Fourteenth channels are show...
This version is based on spring cloud.Finchley.RELEASE） spring boot ( 2.0.4.RELEASE )
Crater 1:spring cloud starts from 2.0., and the dependency packet that needs to be introduced will change. The biggest feature is spring-cloud-starter-.netflix,Many dependent components have more than one Netflix when configuring Maven.Not before.）
Tramp Pit 2: if the version of spring cloud does not match the version of the dependent component, it will go wrong directly. Maven dependency is generally not found in the corresponding jar package.
ps ： If you do not determine the version number correspon...
Note 1:cd xxx
BUILD_ID=DONTKILLME nohup python manage.py runserver 0.0.0.0:8000 &
BUILD_ID=DONTKILLME : Programs running in the background in Jenkins are automatically killed by jenkins, so you need to add BUILDID to this parameter so your program won't be killed.
Evolution of database architecture
In the era of less business data, we can use a single-machine database to meet the business use. With more and more business requests, the amount of data in the database increases rapidly. At this time, the single-machine database can no longer meet the performance requirements of the business, and the database master-slave replication architecture comes into being.
Master-slave replication separates the write operation from the read operation of the database, uses multiple slaver replication to process the read request, Master to process the write reques...
The following demo introduces the use of reflection mechanism to read notes.
First, custom annotations, one to annotate classes, and another to annotate properties, such as the following demo
package Annotation;
import java.lang.annotation.ElementType;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;import java.lang.annotation.Target;
public class TestAnn { @Target(value= {ElementType.TYPE }) @Retention(RetentionPolicy.RUNTIME) public @interface ann{//Used to convert class names to table names. String value();} @Target(value= {ElementType.FIELD }) ...
Write in front of
There are many similar articles on the internet, but on the same road, others may go smoothly and stumble on their own. Record the process of building your own course.
Environmental preparation
1，jira7.3The operation is dependent on the Java environment, that is to say, it is necessary to install JDK and if more than 1.8, it is as follows:
View installed version: RPM -qa|grep java*
You can choose to have multiple versions of the JDK coexist, and I’m simply rude — uninstalled
There are two ways to uninstall, one is normal deletion, the other is strong deletio...
development environment:
> two, configuration
1.GOPATH：This is your working directory. Please add a new GOPATH to the system to specify your working directory and create a new one in the working directory.bin,pkg,srcThree folders.
2.Git：Add the bin directory under the GIT installation directory to the Path environment variable.
3.Using vscode to open the SRC folder, add two files as follows:
{
"files.autoSave": "onFocusChange",
"go.buildOnSave": true,
"go.lintOnSave": true,
"go.vetOnSave": true,
"go.buildTags": "",
"go.buildFlags": [],
"go.lintFlags":...
