Month: December 2018
Spring-Data-JPA @Query annotation Sort sorting
When it is difficult to use method names to achieve the desired query results, we can use @Query to query.@QueryIt is a convenient way to add custom queries.
Using @QueryAnnotation, there are two ways to use annotation, one is JPQL SQL language way, one is native SQL language.
1.User.java Entity class
package com.niugang.entity;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
//javax.persistence.Entit...
The difference between EM, PX and REM
px：IEPX cannot be adjusted as unit font size.
It’s a pixel, a relative length unit, relative to the screen resolution of the display.
em：The font size of the text relative to the current object. 1em=16px;
rem:When the font size is large, although it is still relative size, it has relative HTML root elements.
Oracle Solaris 11.4 GA version released, this will be Solaris’s masterpiece.
On August 28, local time, Oracle officially announced the release of Oracle Solaris 11.4 GA stable version, nearly three years after the release of the previous version 11.3. Oracle product management director Scott LynnThis is the best version of the four Oracle Solaris versions he has participated in.
The news about Solaris is also a little surprising to you. According to our previous reports, Oracle has erased Solaris 12 from the roadmap and fired all Solaris technicians, although there was no official announcement.B, but you can assume that Oracle Solaris 12 has actually been ...
Installation and unloading of Zabbix Agent
cmd /c “C:\zabbix\bin\win64\zabbix_agentd.exe -c c:\zabbix\conf\zabbix_agentd.win.conf -i”cmd /c “C:\zabbix\bin\win64\zabbix_agentd.exe -c c:\zabbix\conf\zabbix_agentd.win.conf -s”
cmd /c “C:\zabbix\bin\win64\zabbix_agentd.exe -c c:\zabbix\conf\zabbix_agentd.win.conf -x”cmd /c “C:\zabbix\bin\win64\zabbix_agentd.exe -c c:\zabbix\conf\zabbix_agentd.win.conf -d”
-c ：Specify all locations of configuration files-i ：Install client-s ：Boot client-x ：Stop client-d ：Uninstall client
Ubuntu package system is broken
Text linkAn error occurred when installing the software and encountered the problem of damage to the package management system. Find solutions on askubuntu.First:sudo apt-get -f install
There is no download to complete the file.Then: sudo apt-get updateThen:Repeat execution
sudo apt-get -f install
Until only the wrong package is left.Then:sudo dpkg —configure -aFinally, clear the cache.sudo apt-get clean
JAVA summary of basic knowledge 6 (one of object-oriented features: polymorphism)
> = On the left, run to see = right.
3，Static functions.
Compile time: refer to whether there are invocation members in the class of the referenced variable.
Runtime: it also refers to the members who are invoked in the class that the reference variable belongs to.
Why is this so?Because static methods do not belong to the object, but belong to the class that the method belongs to.
Invoking the static method reference is the static method in which class the reference is invoked.
Xargs of the linux——–find command
p.p1 { margin: 0.0px 0.0px 0.0px 0.0px; font: 18.0px "Hannotate SC"; color: #0433ff }
p.p2 { margin: 0.0px 0.0px 0.0px 0.0px; font: 17.0px "Hannotate SC" }
p.p3 { margin: 0.0px 0.0px 0.0px 0.0px; font: 17.0px "Hannotate SC"; min-height: 24.0px }
span.s1 { }
span.s2 { font: 18.0px "Hannotate SC"; color: #0433ff }
span.Apple-tab-span { white-space: pre }
Reference blog:
findCommand xargs
findThe difference between – exec and xargs in the command is that the find command passes all matched files together to exec for execution, but passes all matched files in batches to xargs for execution....