oracle的startwithconnectbyprior是根据条件递归查询"树"，分为四种使用情况： 第一种：startwith子节点ID='...'connectbyprior子节点ID=父节点ID1select*frommdm_organizationostartwitho.org_code='10000008'connectbyprio
listagg()WITHINGROUP()SELECTT.DEPTNO,listagg(T.ENAME,',')WITHINGROUP(ORDERBYT.ENAME)namesFROMSCOTT.EMPTWHERET.DEPTNO='20'GROUPBYT.DEPTNO
一、安装redis0、安装wget>yuminstallwget;安装gcc>yuminstallgcc1、新建目录mkdir-p/usr/softwgethttp://download.redis.io/releases/redis-5.0.5.tar.gz或者手动下载之后放到/usr/soft目录下2、解压tar-zxvfredis-5.0.5.tar.gz3、编译和安装进入到re
1、网络配置1.1动态获取IPdhclient1.2静态IP修改/etc/sysconfig/network-scripts/ifcfg-ens33TYPE=EthernetPROXY_METHOD=noneBROWSER_ONLY=no**BOOTPROTO=static**DEFROUTE=yesIPV4_FAILURE_FATAL=noIPV6INIT=yesIPV6_AUTOCONF=ye
第一步、创建Maven工程，配置POM<?xmlversion="1.0"encoding="UTF-8"?><projectxmlns="http://maven.apache.org/POM/4.0.0"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://maven.a
第一步、配置线程池packagecom.kyy.springboot.pool;importorg.springframework.context.annotation.Bean;importorg.springframework.context.annotation.Configuration;importorg.springframework.scheduling.concurrent.Thr
1、ArrayList线程不安全；CopyOnWriteArrayList线程安全packageconcurrent;importjava.util.ArrayList;importjava.util.Iterator;importjava.util.List;importjava.util.concurrent.CopyOnWriteArrayList;/***Auth:zhouhonglian
packageconcurrent;importjava.util.Random;importjava.util.concurrent.Callable;importjava.util.concurrent.ExecutorService;importjava.util.concurrent.Executors;importjava.util.concurrent.Future;/***@Auth
packageconcurrent;importjava.util.concurrent.locks.Condition;importjava.util.concurrent.locks.ReentrantLock;/***Auth:zhouhongliang*Date：2019/8/1*线程等待与唤醒机制Condition*按指定顺序执行线程*/publicclassConditionDemo{
packageconcurrent;importjava.util.concurrent.*;importjava.util.concurrent.locks.ReentrantLock;/***@Auther：zhl*@Date：2019/7/13*@Description：并发测试，重入锁ReentrantLock解决并发问题*/publicclassConcurrentSample{//并发
packageconcurrent;importjava.util.concurrent.BrokenBarrierException;importjava.util.concurrent.CyclicBarrier;importjava.util.concurrent.ExecutorService;importjava.util.concurrent.Executors;/***Auth:zh
packageconcurrent;importjava.text.SimpleDateFormat;importjava.util.Date;importjava.util.concurrent.ExecutorService;importjava.util.concurrent.Executors;importjava.util.concurrent.Semaphore;importjava.
packageconcurrent;importjava.util.Random;importjava.util.concurrent.*;/***Auth:zhouhongliang*Date：2019/8/1*分配多个线程共同执行某个任务，等待子线程都结束，主线程才结束*/publicclassCallableDemo{publicstaticvoidmain(String[]args)thr
packageconcurrent;importjava.util.concurrent.CountDownLatch;importjava.util.concurrent.ExecutorService;importjava.util.concurrent.Executors;/***Auth:zhouhongliang*Date：2019/8/1*CountDownLatch倒计时锁*阻塞主线
一、主程序packagecom.kyy.springboot;importorg.springframework.boot.SpringApplication;importorg.springframework.boot.autoconfigure.SpringBootApplication;/***启动程序*@Auther：zhouhongliang*@Date：2019/7/30*@Descr
1、去除代码中的波浪线~~settings>Editor>Inspections>General>DuplicatedCode复选框不勾选
示例模拟10000次请求，每次并发数为100，每次请求，计数器加1,最后输出计数器值。上代码：packageconcurrent;importjava.util.concurrent.ExecutorService;importjava.util.concurrent.Executors;importjava.util.concurrent.Semaphore;/***@Auther：zhl*@D
开始...1、服务器端：publicclassServerSocketApp{publicstaticvoidmain(String[]args){try{ServerSocketserverSocket=newServerSocket(9999);System.out.println("服务已启动");while(true){Socketsocket=serverSocket.accept();
maven-assembly打包并运行，关键是可以设置MainClass
使用IDEA开发过程中常用的快捷键
简单使用springboot开发，让初学者感受到springboot的强大，只需简单的配置和几行代码就可以构建一个web应用
//初始化1000.155BigDecimalbigDecimal=newBigDecimal(1000.155);//直接舍去小数点后2两位bigDecimal=bigDecimal.setScale(2,BigDecimal.ROUND_DOWN);System.out.println(bigDecimal);//1000.15//去除小数,向上进位bigDecimal=bigDecimal.
阅读目录一、什么是nativemethod二、为什么使用nativemethod三、JVM怎么使nativemethod跑起来四、示例Java调用C语言本地库
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