Java design pattern Decorator Pattern

1, Scenario description (1) Questions In the system, Crystal Report tool is used to generate reports initially, and the reports are sent to the client for viewing. At this time, defining a Crystal Report tool class can complete the generation of crystal reports. The SSRS report service is added to subsequent report tools. At this time, th ...

Posted by luzlin on Mon, 20 Apr 2020 20:36:51 -0700

Important core attribute knowledge of Linux files

1, users Linux is a multi-user, multi task operating system Multiple users: multiple users log in at the same time Multitask: each user can perform multiple tasks User: Management of Linux system Users are generally divided into user name and user ID (UID) The user name is convenient for the administrator to use, and the user ID is the o ...

Posted by Hybrid Kill3r on Fri, 10 Apr 2020 06:44:04 -0700

Ubuntu TFTP service building and exception maintenance

TFTP is a file transfer protocol similar to FTP, but it does not require user authentication and cannot list directories. The TFTP server always listens for requests from PXE clients on the network. When it detects that PXE client requests PXE service in the network, it will provide network data package containing boot ...

Posted by Vermillion on Thu, 09 Apr 2020 11:03:26 -0700

The installation of ES cluster and the use of plug-ins

ES cluster installation 1)ELK is a log analysis platform, not a software, but a complete set of solutions. It is the acronym of three software products. ELK represents: Elasticsearch: responsible for log retrieval and storage Logstash: responsible for the collection, analysis and processing of logs Ki ...

Posted by pradeepmamgain on Sun, 15 Mar 2020 02:32:31 -0700

Formal learning linux-13

1.vsftpd main configuration file The main configuration file (/ etc/vsftpd/vsftpd.conf), which contains a lot of annotation information, has little actual parameter information. [root@linuxprobe ~]# mv /etc/vsftpd/vsftpd.conf /etc/vsftpd/vsftpd.conf_bak [root@linuxprobe ~]# grep -v "#" /etc/vsftpd/vsftpd.conf_bak > /etc/vsftpd/vsftpd.conf ...

Posted by Fataqui on Sat, 14 Mar 2020 21:10:22 -0700

linux configuration firewall configuration

Article directory 1, The concept of firewall 2, Firewall configuration 1. View firewall commands 2. Configure firewall commands 3, centos7 and below 4, Cloud platform access policy configuration 5, Copyright notice 1, The concept of firewall Firewall technology is a kind of technology that hel ...

Posted by Datnigz2002 on Mon, 09 Mar 2020 19:58:46 -0700

#Network programming -- Example of TCP ECHO echo programming

Article directory Flow protocol and packet sticking Sticky bag readn writen Client sends fixed length package code Echo client / server echosrv.c echocli.c Reference material Flow protocol and packet sticking TCP is a transport service based on byte stream. It has no boundary and can not guar ...

Posted by dethron on Tue, 25 Feb 2020 23:16:25 -0800

Network commands in linux

write explain Command name: write Command path / usr/bin/write Execute permission: all users Function Description: send information to the user, and save with Ctrl+D grammar Write < user name > Example # Send a message to tenentity write eternity [root@izm5e2q95pbpe1hh0kkwoiz ~]# write eternity write: eternity is logged in more than o ...

Posted by pdpullmn612 on Wed, 19 Feb 2020 04:49:04 -0800

CoolFire lecture series lecture 1

Author: CoolFire [coolfires@hotmail.com] (2001-10-12 15:00:00) CoolHC Volume 1 By CoolFire Author E-Mail: coolfires@hotmail.com Lin Zhenglong, a famous hacker in Taiwan, is the leader of Chinese hackers. Won COG information security Lifetime Achievement Award in 2011Lin Zhenglong Baidu Encycl ...

Posted by random1 on Tue, 11 Feb 2020 22:57:36 -0800

Install R's machine learning GUI tool rattle package

This is a good tool for R to play machine learning. Install the rattle() package &gt; install.packages("rattle") &gt; library(rattle) Rattle: A free graphical interface for data science with R. XXXX 5.3.0 Copyright (c) 2006-2018 Togaware Pty Ltd. //Type 'rattle()' to flick, wiggle, and tumble your data. Rattler, you're too naughty Ru ...

Posted by grga on Sun, 02 Feb 2020 03:01:36 -0800