aircjm

1. 初步的调研，初步调研从企业的一些战略目标的角度来考虑问题，分析问题。 
2. 确立项目的目标，确认系统的目标要达成什么样的目标？1 
3. 再拆分，大致拆分一下子系统 
4. 接下来拟定方案 
5. 再进行可行性研究，他的输出产物：得到可行性研究报告 
6. 最后制定系统方案 他的输出产物：系统设计任务书


可行性分析需要从哪几个方面？ 
经济可行性

aircjm

#!/bin/bash
set -o errexit
 
# Author: David Underhill
# Script to permanently delete files/folders from your git repository.  To use 
# it, cd to your repository's root and then run the script with a list of paths
# you want to delete, e.g., git-delete-history path1 path2
 
if [ $# -eq 0 ]; then
    exit 0

aircjm

package main

import "fmt"

//  golang map相关 包含 定义 修改 遍历
func main() {

	// 创建一个hashmap  通过make(map[key_type]value_type) 来创建对应的map
	ageMap := make(map[int32]string)

aircjm

brew install homebrew/cask/docker
brew install go
brew install z
brew install zsh-autosuggestions
brew install zsh-syntax-highlighting
brew install redis
brew install android-file-transfer
brew install istat-menus
brew install sourcetree
brew install anki

aircjm

public class RedisDistributionLock {

    private static final Logger logger = LoggerFactory.getLogger(RedisDistributionLock.class);

    //key的TTL,一天
    private static final int finalDefaultTTLwithKey = 24 * 3600;

    //锁默认超时时间,20秒
    private static final long defaultExpireTime = 20 * 1000;

aircjm

package com.uorca.current.unit3;

import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

/**
 * 定时任务 两种不同的定时任务
 */
public class ScheduledExecutorServiceDemo {

aircjm

package com.uorca.unit3;

import java.util.concurrent.locks.ReentrantLock;

/**
 * 公平锁测试
 */
public class FairLock implements Runnable {

    // 设置锁是公平的。公平值得是按照时间先后的顺序，保障先到者获取资源。

aircjm

package com.uorca.unit3;

import java.util.concurrent.locks.ReentrantLock;

/**
 * 必须获取lock1和lock2的锁才能正确的执行下去，tryLock无参方法会在等待一段时间后跳出
 */
public class TryLock implements Runnable {

    public static ReentrantLock lock1 = new ReentrantLock();

aircjm

package com.uorca.unit3;

import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.ReentrantLock;

/**
 * 测试重入锁的限时等待功能
 */
public class TimeLock implements Runnable {

aircjm

package com.uorca.unit3;

import java.util.concurrent.locks.ReentrantLock;

/**
 * 重入锁竞争，测试中断响应功能
 */
public class IntLock implements Runnable {

    public static final ReentrantLock lock1 = new ReentrantLock();