HiSEN

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Posted on Edited on Symbols count in article: 1.3k Reading time ≈ 1 mins.

这个接口为免费的

一、接口地址

等号后面的为需要翻译的英文

1
http://fanyi.youdao.com/openapi.do?keyfrom=xinlei&key=759115437&type=data&doctype=json&version=1.1&q=hisen

二、代码样例

把全世界200+国家和地区的名字翻译为英文，并且入库

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@Autowired
SmsCountryService countryService;

@Test
public void updateZhName(){
  // 有道翻译接口
  String url = "http://fanyi.youdao.com/openapi.do?keyfrom=xinlei&key=759115437&type=data&doctype=json&version=1.1&q=";
  // 查询出所有的英文国家名字
  List<SmsCountry> countries = countryService.queryAllName();
  // httpclient
  CloseableHttpClient client = HttpClientBuilder.create().build();
  // 翻译每个国家的名字，并且更新数据库
  for (SmsCountry country:countries) {
    HttpGet request = new HttpGet(url + URLEncoder.encode(country.getName()));
    try {
      CloseableHttpResponse response = client.execute(request);
      String str = EntityUtils.toString(response.getEntity(), "utf-8");
      JSONObject jsonObject = JSON.parseObject(str);
      // 取出json字符串中数组的值
      String s = (String) jsonObject.getJSONArray("translation").get(0);
      System.out.println(">>>>> " + s);
      if (!StringUtil.isEmpty(s)){
      SmsCountry smsCountry = new SmsCountry();
      smsCountry.setId(country.getId());
      smsCountry.setNameZh(s);
      countryService.updateNameById(smsCountry);
      }
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
}

Posted on Edited on Symbols count in article: 2.1k Reading time ≈ 2 mins.

利用Java8的流和lambda表达式能很方便的对list对象进行去重
而且不会造成代码入侵

插播：Java8 对List进行求和、分组、提取对象单个属性：https://www.jianshu.com/p/c71eaeaaf30c

下面的例子仅供参考
github：https://github.com/hisenyuan

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package com.hisen.collection.list.duplicate;

import com.alibaba.rocketmq.shade.com.alibaba.fastjson.JSON;
import Java.util.ArrayList;
import Java.util.List;
import Java.util.concurrent.ConcurrentHashMap;
import Java.util.function.Function;
import Java.util.function.Predicate;
import Java.util.stream.Collectors;

/**
 * @author hisenyuan
 * @time 2018/4/19 14:06
 * @description list对象根据属性去重 lambda + stream
 */
public class ListDuplicateTest {


    public static void main(String[] args) {
        List<Person> list = new ArrayList<>();
        for (int i = 0; i < 100; i++) {
            Person person = new Person();
            person.setAge(10);
            person.setName("hsien");
            person.setWeight(i);
            list.add(person);
        }
        Person bean = new Person();
        bean.setName("hisenyuan");
        bean.setAge(33);
        bean.setWeight(65);
        list.add(bean);

        List<Person> collect = list.stream().filter(distinctByKey(Person::getName))
                .collect(Collectors.toList());
        System.out.println(JSON.toJSONString(collect));
    }

    /**
     * 函数式接口 T -> bollean
     * @param keyExtractor
     * @param <T>
     * @return
     */
    public static <T> Predicate<T> distinctByKey(Function<? super T, ?> keyExtractor) {
        ConcurrentHashMap<Object, Boolean> map = new ConcurrentHashMap<>(16);
        return t -> map.putIfAbsent(keyExtractor.apply(t),Boolean.TRUE) == null;

//        这个也可以，不过感觉效率要低一些，线程不是那么安全
//        Set<Object> seen = ConcurrentHashMap.newKeySet();
//        return t -> seen.add(keyExtractor.apply(t));
    }

    /**
     * 内部类
     */
    static class Person {
        private int age;
        private String name;
        private int weight;

        public int getAge() {
            return age;
        }

        public void setAge(int age) {
            this.age = age;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public int getWeight() {
            return weight;
        }

        public Person() {
        }
        public void setWeight(int weight) {
            this.weight = weight;
        }
    }
}

Posted on Edited on In Symbols count in article: 1.6k Reading time ≈ 1 mins.
1
effective Java # 2

Builder模式，不直接生成想要的对象，而是让客户端利用所有必要的参数调用构造器，

得到一个builder对象。然后客户端在builder对象上调用类似于setter的方法，

来设置每个相关可选的参数，最后调用无参的build来生成不可变的对象。

完整代码+测试：github:完整代码+测试

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public class NutritionFacts {

  private final int servingSize;
  private final int servings;
  private final int calories;
  private final int fat;
  private final int sodium;
  private final int carbohydrate;

  private NutritionFacts(Builder builder) {
    servingSize = builder.servingSize;
    servings = builder.servings;
    calories = builder.calories;
    fat = builder.fat;
    sodium = builder.sodium;
    carbohydrate = builder.carbohydrate;
  }

  public static class Builder {

    // Required parameters
    private final int servingSize;
    private final int servings;

    private int calories = 0;
    private int fat = 0;
    private int carbohydrate = 0;
    private int sodium = 0;

    public Builder(int servingSize, int servings) {
      this.servingSize = servingSize;
      this.servings = servings;
    }

    public Builder calories(int val) {
      calories = val;
      return this;
    }

    public Builder fat(int val) {
      this.fat = val;
      return this;
    }

    public Builder carbohydrate(int val) {
      this.carbohydrate = val;
      return this;
    }

    public Builder sodium(int val) {
      this.sodium = val;
      return this;
    }

    public NutritionFacts build() {
      return new NutritionFacts(this);
    }
  }



  @Override
  public String toString() {
    return "NutritionFacts{" +
        "servingSize=" + servingSize +
        ", servings=" + servings +
        ", calories=" + calories +
        ", fat=" + fat +
        ", sodium=" + sodium +
        ", carbohydrate=" + carbohydrate +
        '}';
  }
}

Posted on Edited on In Symbols count in article: 469 Reading time ≈ 1 mins.

effective Java：

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单元素的枚举类型已经成为实现Singleton的最佳方法

理由：

  1. 因为枚举单例有序列化和线程安全的保证
  2. 避免反射和并发困扰

单例模式模式：完整代码+测试

主要代码：

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public class EnumSingleton {

  private EnumSingleton() {
  }

  public static EnumSingleton getInstance() {
    return Singleton.INSTANCE.getInstance();
  }

  private enum Singleton {
    INSTANCE;
    private EnumSingleton singleton;

    Singleton() {
      singleton = new EnumSingleton();
    }

    public EnumSingleton getInstance() {
      return singleton;
    }
  }
}

Posted on Edited on In Symbols count in article: 5.3k Reading time ≈ 5 mins.

忘记开始是在什么地方看到docker这个东西

后面觉得挺好玩，也试了很多次，找过很多的教程。

搭建了一个zookeeper的集群(docker-compose)

然后当我需要搭建redis集群的时候，发现里面很多的概念还不是很懂

比如：volume network

然后加了docker的群，遇到了在以前idea群里面熟的一个人

花了一天的时间看完他传的一本书，昨天买的几本书晚上也到了。
（docker从入门到实践、Java并发编程的艺术、effective Java中文版 2）

这本书总体来说还行，就是过时了，还在用link，毕竟三年前的东西

有些例子也报错，主要是ruby相关的不行，提醒需要2.2以上的版本

下面是随便做的一点笔记

Read more »

Posted on Edited on In Symbols count in article: 3.2k Reading time ≈ 3 mins.

一个简单的工具类，更多Java小练习：https://github.com/hisenyuan/IDEAPractice

一、添加依赖

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<!-- POI start -->
<dependency>
  <groupId>org.apache.poi</groupId>
  <artifactId>poi</artifactId>
  <version>3.9</version>
</dependency>
<dependency>
  <groupId>org.apache.poi</groupId>
  <artifactId>poi-ooxml</artifactId>
  <version>3.9</version>
</dependency>
<dependency>
  <groupId>commons-collections</groupId>
  <artifactId>commons-collections</artifactId>
  <version>3.2.2</version>
</dependency>
<!-- POI end -->

二、测试类

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package com.hisen.jars.poi;

import Java.io.File;
import Java.io.IOException;
import Java.util.Arrays;
import Java.util.List;

/**
 * @author hisenyuan
 * @time 2018/1/12 17:43
 * @description 测试读取
 */
public class TestPoiExcelUtil {

  public static void main(String[] args) {
    File file = new File("C:\\work\\document\\银行信息.xlsx");
    try {
      // 每一个excelData为一行数据（存放在数组）
      List<String[]> excelData = POIExcelUtil.readExcel(file);
      for (String[] data:excelData) {
        System.out.println(Arrays.toString(data));
      }
    } catch (IOException e) {
      e.printStackTrace();
    }
  }

}

三、工具类代码

完整类：POIExcelUtil.Java

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package com.hisen.jars.poi;

import Java.io.File;
import Java.io.FileInputStream;
import Java.io.FileNotFoundException;
import Java.io.IOException;
import Java.io.InputStream;
import Java.util.ArrayList;
import Java.util.List;
import org.apache.log4j.Logger;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

/**
 * @author hisenyuan
 * @time 2018/1/12 16:35
 * @description 利用POI读取excel表格
 */
public class POIExcelUtil {

  private static Logger logger = Logger.getLogger(POIExcelUtil.class);
  private final static String XLS = "xls";
  private final static String XLSX = "xlsx";

  public static List<String[]> readExcel(File file) throws IOException {
    // 检查文件
    checkFile(file);
    Workbook workBook = getWorkBook(file);
    // 返回对象,每行作为一个数组，放在集合返回
    ArrayList<String[]> rowList = new ArrayList<>();
    if (null != workBook) {
      for (int sheetNum = 0; sheetNum < workBook.getNumberOfSheets(); sheetNum++) {
        // 获得当前sheet工作表
        Sheet sheet = workBook.getSheetAt(sheetNum);
        if (sheet == null) {
          continue;
        }
        // 获得当前sheet的开始行
        int firstRowNum = sheet.getFirstRowNum();
        // 获得当前sheet的结束行
        int lastRowNum = sheet.getLastRowNum();
        // 循环所有行(第一行为标题)
        for (int rowNum = firstRowNum; rowNum < lastRowNum; rowNum++) {
          // 获得当前行
          Row row = sheet.getRow(rowNum);
          if (row == null) {
            continue;
          }
          // 获得当前行开始的列
          short firstCellNum = row.getFirstCellNum();
          // 获得当前行的列数
          int lastCellNum = row.getPhysicalNumberOfCells();
          String[] cells = new String[row.getPhysicalNumberOfCells()];
          // 循环当前行
          for (int cellNum = firstCellNum; cellNum < lastCellNum; cellNum++) {
            Cell cell = row.getCell(cellNum);
            cells[cellNum] = getCellValue(cell);
          }
          rowList.add(cells);
        }
      }
    }
    return rowList;
  }
}

Posted on Edited on In Symbols count in article: 2.3k Reading time ≈ 2 mins.

一、说明

利用redis操作的原子性，实现Java 多线程并发的情况下实现计数器。

我本机测试多个线程操作之后，结果会出现一定的延迟，但是最终数字是ok的

应该是redis内部做了一个类似于队列的功能。

需要注意的是，得使用redis连接的线程池，不然会出现异常

这里有一个：JedisUtil 下面用到了

二、 代码实现

2.1 redis操作类

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package com.hisen.thread.count_click_by_redis;

import com.hisen.utils.JedisUtil;
import redis.clients.jedis.JedisPool;
/**
 * @author hisenyuan
 * @description 操作redis的线程类
 */
public class ClickRedis {

  /**
   * 必须使用线程池，而且线程池要大于并发数，否则会出现redis超时
   */
  private static JedisPool jedis = JedisUtil.getPool();

  public static void click() {
    jedis.getResource().incrBy("hisen", 1);
  }

  public static int getCount() {
    return Integer.parseInt(jedis.getResource().get("hisen"));
  }

  public static void declare() {
    jedis.getResource().del("hisen");
    jedis.close();
  }
}

2.2 线程类,模拟点击

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package com.hisen.thread.count_click_by_redis;

/**
 * @author hisenyuan
 * @description 执行点击的线程类
 */
public class CountClickByRedisThread extends Thread{

  private int id;
  public CountClickByRedisThread(int id) {
    this.id = id;
  }

  @Override
  public void run() {
    super.run();
    ClickRedis.click();
    int count = ClickRedis.getCount();
    System.out.println("task:" + id + "\t 执行完毕\t线程编号：" + this.getId() + "\t当前值：" + count);
  }
}

2.3 主线程 - 启动类

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package com.hisen.thread.count_click_by_redis;

import Java.util.concurrent.ArrayBlockingQueue;
import Java.util.concurrent.ThreadPoolExecutor;
import Java.util.concurrent.TimeUnit;

public class Main {

  public static void main(String[] args) throws InterruptedException {
    /**
     * 5 - corePoolSize：核心池的大小
     * 10 - maximumPoolSize：线程池最大线程数，它表示在线程池中最多能创建多少个线程
     * 200 - keepAliveTime：表示线程没有任务执行时最多保持多久时间会终止。
     * unit - unit：参数keepAliveTime的时间单位，有7种取值
     * workQueue：一个阻塞队列，用来存储等待执行的任务
     */
    ThreadPoolExecutor executor = new ThreadPoolExecutor(
        50,
        100,
        200,
        TimeUnit.MICROSECONDS,
        new ArrayBlockingQueue<Runnable>(50));
    // 开启50个线程
    for (int i = 0; i < 50; i++) {
      executor.execute(new CountClickByRedisThread(i));
    }
    System.out.println("已经开启所有的子线程");
    // 启动一次顺序关闭，执行以前提交的任务，但不接受新任务。
    executor.shutdown();
    // 判断所有线程是否已经执行完毕
    while (true) {
      if (executor.isTerminated()) {
        System.out.println("所有的子线程都结束了！");
        // 清除redis数据
        ClickRedis.declare();
        break;
      }
      Thread.sleep(100);
    }
  }

}

Posted on Edited on In Symbols count in article: 4.2k Reading time ≈ 4 mins.

零、rabbitMQ介绍

rabbitMQ详细介绍

  1. 如果某个queue有多个订阅，消息分均分到消费者，而不是所有人都收到全部
  2. 接收消息有ack(acknowledgment)机制，发送消息是没有这个机制的
  3. 生产者将消息发送到Exchange（交换器），由Exchange将消息路由到一个或多个Queue中（或者丢弃）。

一、在ununtu上安装

1.1 安装

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echo 'deb http://www.rabbitmq.com/debian/ testing main' | sudo tee /etc/apt/sources.list.d/rabbitmq.list

wget -O- https://www.rabbitmq.com/rabbitmq-release-signing-key.asc | sudo apt-key add -

sudo apt-get update

sudo apt-get install rabbitmq-server

1.2 配置

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# 打开管理页面功能
sudo rabbitmq-plugins enable rabbitmq_management
# 查看安装的插件
sudo rabbitmqctl list_users
# 查看用户
sudo rabbitmqctl list_users
# 新增管理员用户
sudo rabbitmqctl add_user admin admin
# 授予管理员权限
sudo rabbitmqctl set_user_tags admin administrator
# 管理页面地址，用刚设置的账户登录管理页面

http://127.0.0.1:15672

二、Java小Demo

2.1 遇到的问题

  1. ACCESS_REFUSED - Login was refused using authentication mechanism PLAIN.
    帐号密码错误，建议使用2.3配置的账户，guest账户不靠谱

  2. connection error
    ip或者port错误，确认信息是否正确，虚拟机的话看看端口映射是否正常

2.2 配置用户

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# 添加普通用户
sudo rabbitmqctl add_user hisen hisen
# 添加权限
rabbitmqctl set_permissions -p "/"  hisen ".*" ".*" ".*"
# 列出用户权限
rabbitmqctl list_user_permissions hisen

2.3 添加maven依赖

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<dependency>
  <groupId>com.rabbitmq</groupId>
  <artifactId>amqp-client</artifactId>
  <version>5.0.0</version>
</dependency>

2.4 发送端代码

Read more »

Posted on Edited on In Symbols count in article: 2.8k Reading time ≈ 3 mins.

使用ubuntu官方发布的docker镜像进行二次修改

这是一个菜鸟的脚本，执行命令应该是使用 & 连接，一个RUN命令搞定

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FROM    ubuntu
MAINTAINER      Fisher "hisenyuan@gmail.com"
RUN     /bin/echo 'root:hisen' |chpasswd
RUN     useradd hisen
RUN     /bin/echo 'hisen:hisen' |chpasswd
RUN     /bin/echo -e "LANG=\"en_US.UTF-8\"" >/etc/default/local
# 显示系统位数
RUN		uname -p
# 清空源 
RUN     echo "" > /etc/apt/sources.list
# 更换为阿里云源
RUN		echo "deb http://mirrors.aliyun.com/ubuntu/ xenial main restricted universe multiverse" >> /etc/apt/sources.list
RUN		echo "deb http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted universe multiverse" >> /etc/apt/sources.list
RUN		echo "deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted universe multiverse" >> /etc/apt/sources.list
RUN		echo "deb http://mirrors.aliyun.com/ubuntu/ xenial-proposed main restricted universe multiverse" >> /etc/apt/sources.list
RUN		echo "deb http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse" >> /etc/apt/sources.list
RUN		echo "deb-src http://mirrors.aliyun.com/ubuntu/ xenial main restricted universe multiverse" >> /etc/apt/sources.list
RUN		echo "deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted universe multiverse" >> /etc/apt/sources.list
RUN		echo "deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted universe multiverse" >> /etc/apt/sources.list
RUN		echo "deb-src http://mirrors.aliyun.com/ubuntu/ xenial-proposed main restricted universe multiverse" >> /etc/apt/sources.list
RUN		echo "deb-src http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse" >> /etc/apt/sources.list
# 更新源
RUN		apt-get update
# 安装软件
RUN     apt-get -y install vim
RUN     apt-get -y install curl
RUN     apt-get -y install wget
RUN     apt-get -y install net-tools
RUN     apt-get -y install iputils-ping
RUN     apt-get -y install git
# 创建软件文件夹
RUN     mkdir -p /usr/hisen/soft/Java
RUN     mkdir -p /usr/hisen/soft/tomcat
RUN     mkdir -p /usr/hisen/soft/maven
RUN     mkdir -p /usr/hisen/soft/download
# 添加本地软件包到指定文件夹（会自动解压，软件压缩包必须放在docker同级目录）
ADD jdk-8u151-linux-x64.tar.gz /usr/hisen/soft/Java/
ADD apache-tomcat-8.5.24.tar.gz /usr/hisen/soft/tomcat/
ADD apache-maven-3.5.2-bin.tar.gz /usr/hisen/soft/maven/

# 配置环境变量
# Java
ENV JAVA_HOME=/usr/hisen/soft/Java/jdk1.8.0_151
ENV JRE_HOME=$JAVA_HOME/jre
ENV CLASSPATH=.:$CLASSPATH:$JAVA_HOME/lib:$JRE_HOME/lib
ENV PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
# tomcat
ENV CATALINA_HOME=/usr/hisen/soft/tomcat/apache-tomcat-8.5.24
ENV CLASSPATH=.:$JAVA_HOME/lib:$CATALINA_HOME/lib
ENV PATH=$PATH:$CATALINA_HOME/bin
# maven
ENV MAVEN_HOME=/usr/hisen/soft/maven/apache-maven-3.5.2
ENV MAVEN_OPTS="-Xms256m -Xmx512m"
ENV PATH=${MAVEN_HOME}/bin:$PATH

# 监听端口
EXPOSE  22
EXPOSE  80
EXPOSE  8080
CMD     /usr/sbin/sshd -D