Then we found another more simple and effective way
1. From http://download.csdn.net/download/qq_ 38355313/12156696 download the common package you need
2. Directly put the required module into the LIBS folder
3. Add the original
implementation fileTree(include: ['*.jar'], dir: 'libs')
Change to
implementation fileTree(include: ['*.jar','*.aar'], dir: 'libs')
This problem can be solved, and the pro test is effective.
When configuring webpack.config.js to automatically package, an Error: Cannot find module’@babel/core’ error occurred. I
initially thought that babel-core was not installed. After reinstalling babel-core several times, it still doesn’t work. Compared with the previous project, it is found that the version of babel-loader is different. The previous one was @7.1.5 version, but now it is @8.0.0 version.
Install back to the @7.1.5 version with a dubious mood
npm uninstall babel-loader
npm install babel-loader@7.1.5
And then npm run buildfound success!
I’m a little puzzled, it’s only a few days since the last installation, so I updated it to [email protected]. And it doesn’t support the original configuration anymore. No solution was found on the Internet, and the principle is still unclear. Mark it first, and after solving the problem of @8.0.0, I will come back to add.
Attach webpack.config.js code:
var webpack = require('webpack');
var path = require('path');
var HtmlWebpackPlugin = require('html-webpack-plugin');
module.exports = {
entry: __dirname + '/client/root/index',
output: {
path: path.join(__dirname + '/dist'),
filename: 'bundle.js',
},
module: {
loaders : [{
test :/(\.jsx|\.js)$/,
exclude : /node_modules/,
loader :'babel-loader',
options:{
presets:[
"env", "react",
]
}
},
{
test: /\.css$/,
loader: 'style-loader!css-loader'
},
{
test: /\.less$/,
loader: 'style-loader!css-loader!less-loader'
},
{
test: /\.(jpg|.png)$/,
loader: 'url-loader'
}
]
},
plugins: [
new HtmlWebpackPlugin({
template: __dirname + '/client/views/template.html'
}),
]
}
Regarding the [email protected]cause of the error has been found, thank you @Sky__zt for your answer.
(Forgot to read the official document)
The official default babel-loader | babel corresponding version needs to be the same: that is, the babel-loaderlatest version is requiredbabel
For details, please refer to: “npm_babel-loader”
Two solutions: 1. Roll back the lower version
npm install -D babel-loader@7 babel-core babel-preset-env
npm install -D babel-loader @babel/core @babel/preset-env webpack
phenomenon:
When I started the project today, this project used the Elasticsearch service and found that the background reported this error:
Caused by: io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: no further information: /127.0.0.1:9300
The error message is shown as below:
the reason:
This project uses the Elasticsearch search service, and the error message also prompts key information such as elasticsearch.transport. In fact, this error is caused by the failure of the Elasticsearch service to start successfully.
solution:
Restart the Elasticsearch service (if it doesn’t work once, try shutting it down and then restarting it).
I restarted several times before it succeeded.
When I created a new Vue project today, I made a mistake like the title, which was disgusting at that time
Try the method of online God
Find the content to be modified by C:: (users/owner). Vuerc “ Usetaobaoregistry “: false, if the value is true or false, it is not easy to use
Then a whim called CMD as administrator to recreate the project successfully
For reference only, by the way, ask if there is a big God how to solve this problem: how to make the CMD run smoothly under the permission of non administrator?
Today, we use C + + to encapsulate a function of OpenSSL. When a parameter forgets to assign a value, (the last one) prompts this (as shown in the figure below, I intentionally set it to a null value). But it’s hard.
Springboot project running error:
If you check the directory, the problem lies in the URL in the controller
(1) if: @ requestmapping (“/”)
the URL should be written:
(2) if the URL is like this:
Then @ requestmapping (“/ users”)
is a very simple question… As a result, I took a long walk to look at the XML file and properties for half a day… To record this little problem
Cmake error: the source directory “opencv installation directory” does not appear to contain cmakelists.txt
I want to build opencv 4.5.0 in Ubuntu 20.04 this morning; In the C + + environment, I tried to learn opencv in the Linux system, but I was not familiar with the use of Linux system. I was puzzled by one step in building the environment, and the error was as follows:
Cmake error: the source directory “opencv installation directory” does not appear to contain cmakelists.txt
In Baidu search, we found many solutions provided by big men. After some attempts, we failed collectively. After carefully studying the reasons for the error and checking our opencv installation directory, we found that the specific path of our cmakelists.txt is "home"/ ××××/ Opencv/opencv master/cmakelists.txt " instead of " home/ ×××/ Opencv/cmakelists. TXT ", finally found the cause of the error and solved the problem. Therefore, I hope this article can help some beginners like me. Thank you for your support!
This error occurs because a page appears in your Vue router global navigation guard, jumps to a page and then redirects to another interface
router.beforeEach((to,from,next)=>{
if(to.matched.some(record => record.meta.requiresAuth)){
if(!store.state.user){
//Jump to the landing page
next({
name:'login',
query:{//Pass the query string parameter via url
redirect: to.fullPath//Tell the landing page the page that needs to be returned if the login is successful
}
})
}else{
next()
}
}else{
next()
}
next()
})
If such code appears in Vue router, this error will occur. The solution is not to use multi-layer if and else
IO Error: The Network Adapter could not establish the connection
The Network Adapter could not establish the connection
The Network Adapter could not establish the connection
Connection timed out: connect, socket connect lapse 21004 ms. /10.10.10.3 1521 0 1 true
Connection timed out: connect, socket connect lapse 21004 ms. /10.10.10.3 1521 0 1 true
Connection timed out: connect
Connection timed out: connect
the database is 19C rac PDB environment, the current test even one of the VIP address, through the VPN, sqlplus and PL/SQL tools can connect to the database, but with Oracle sql The developer tool reported an error. Later, it tried dbeaver and dbvisualizer. It’s strange.
When using the dbeaver tool, we find that the connection is jdbc:oracle :thin
Think of these tools to go is it, so query
By searching jdbc:oracle : the network adapter could not establish the connection
Find the configuration file below:
Add this Addvmoption – DJava. Net. Preferipv4stack = true restart the client tool and connect again successfully.
relevant:
Dbeaver is modified as follows: dbeaver.ini
add to
-Djava.net.preferIPv4Stack=true
Error: undefined reference to ` xxx ‘in C + + means that an undefined method is referenced. There are many reasons for this problem. Here are two problems I encountered.
1. The corresponding header file is not referenced or the versions of library functions referenced in the header file are inconsistent. In different versions of libraries, the names of the same implementation method may be inconsistent, which causes this problem.
2. The method of using extern keyword is wrong. There are many uses of extern. The function of extern here is to refer to functions of other files.
a.h:
//a.h
#ifndef AH
#define AH
extern int test();//Here the return type and parameters must be the same as the implementation method
#endifaaa.cpp
//aaa.cpp
#include <stdio.h>
#include <iostream>
#include "a.h" //Both need to refer to the corresponding header file, otherwise an error will be reported
using namespace std;
int test()
{
cout << "abc" <<endl;
}bbb.cpp
//bbb.cpp
#include <stdio.h>
#include <iostream>
#include "a.h" //Both need to refer to the corresponding header file, otherwise an error will be reported
int main()
{
test();
}
Results of operation:
If any cpp file does not refer to the corresponding header file, an error will be reported.
When using the infinite scroll of element UI, the error occurs. The data displayed asynchronously has no initial data, and then the requested data is displayed. The error is reported when the initial data is displayed
just set an initial value for the error value
or add a judgment to render the data when there is data, and not display it when there is no data.
import requests
url = 'http://10.165.153.210/getToken'
headers = {
'Content-Type': 'application/json'
}
payload = {
'username': 'pad_view',
'password': '6368da1213cd4c4538128a0e9acd0288'
}
res = requests.post(url=url,method='post', data=payload, headers=headers)
print(res.text)3. Reasons
When you request to pass parameters, the JSON string and dictionary look the same, but the background serialization format is different. Therefore, a JSON parsing error will be reported when data is passed in
4. Solutions
Convert dictionary object to JSON string
4.1 import JSON
import json
4.2 convert dictionary object to JSON string
payload = json.dumps({
'username': 'username',
'password': 'password'
})
4.3 complete modification code, as follows
import requests
import json # import json
url = 'http://10.165.153.210/getToken'
headers = {
'Content-Type': 'application/json'
}
# Convert a dictionary object into a json string, using the json.dumps() method
payload = json.dumps({
'username': 'pad_view',
'password': '6368da1213cd4c4538128a0e9acd0288'
})
res = requests.post(url=url,method='post', data=payload, headers=headers)
# Print the response message
print(res.text)