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  • .NET CORE与Spring Boot编写控制台程序应有的优雅姿势

    本文分别说明.NET CORE与Spring Boot 编写控制台程序应有的“正确”方法,以便.NET程序员、JAVA程序员可以相互学习与加深了解,注意本文只介绍用法,不会刻意强调哪种语言或哪种框架写的控制台程序要好。

    本文所说的编写控制台程序应有的“正确”方法,我把正确二字加上引号,因为没有绝对的正确,因人而异,因系统设计需求而异,我这里所谓的正确方法是指使用面向对象,依赖注入IOC,切面控制AOP等编码规范来提升程序的性能、整洁度、可读性、可维护性等,最终达到让人感觉有点高大上,有点优雅的样子

    先来说说.NET CORE编写控制台程序,目前网络上大把的讲解ASP.NET CORE的编写规范,反而对于.NET CORE控制台程序编写规范介绍比较少,大多停留在Hello Word 程序中,而本文则来讲讲.NET CORE控制台的编写规范(应有的优雅姿势)^ v ^

     如果说不讲什么IOC,DI,AOP等,不讲扩展性,规范性,全部面向过程(方法)编程,那估计没什么好讲的,因为无非就是定义一个class,然后在class中定义一堆的method(方法),如果在方法中需要使用到其它第三方组件,则直接单独引用,引用后进行简单封装util工具类的静态方法,甚至也不用封装,直接使用原生的方法,总之全部都是方法调方法。而这里所演示的编写控制台方法均是尽可能的使用.NET CORE所具有的特性,只有这样才能体现出.NET CORE框架的优势,否则普通控制台程序与.NET CORE控制台程序有什么区别。

    编写.NET CORE控制台程序优雅姿势一:(直接使用.NET CORE的 IOC、Logging、Config组件)

    代码如下:

    //Program.cs
    
    using Microsoft.Extensions.DependencyInjection;
    using System;
    using Microsoft.Extensions.Logging;
    using Microsoft.Extensions.Configuration.Json;
    using Microsoft.Extensions.Configuration;
    using System.IO;
    
    namespace NetCoreConsoleApp
    {
        class Program
        {
            static void Main(string[] args)
            {
                //设置config文件
                var config = new ConfigurationBuilder()
                                    .SetBasePath(Directory.GetCurrentDirectory())
                                    .AddJsonFile("appSettings.json", optional: true, reloadOnChange: true).Build();
    
                //设置依赖注入
                var provider = new ServiceCollection()
                                        .AddLogging(configLogging => //设置日志组件
                                        {
                                            configLogging.SetMinimumLevel(LogLevel.Information);
                                            configLogging.AddConsole();
                                        })
                                       .AddScoped<IConfiguration>(p => config)
                                       .AddScoped<HostService>()
                                       .BuildServiceProvider();
    
                var hostService = provider.GetService<HostService>();
    
                hostService.RunAsync();//统一入口服务
    
                Console.WriteLine("提示:程序已正常启动运行,按任意键停止运行并关闭程序...");
                Console.ReadLine();
    
            }
        }
    }
    
    
    //HostService.cs
    using Microsoft.Extensions.Configuration; using Microsoft.Extensions.Logging; using System; using System.Diagnostics; using System.Threading; using System.Threading.Tasks; namespace NetCoreConsoleApp { public class HostService { private readonly IConfiguration config; private readonly ILogger<HostService> logger; public HostService(IConfiguration config, ILogger<HostService> logger) { this.config = config; this.logger = logger; } public void RunAsync() { Task.Run((Action)Execute); } /// <summary> /// 控制台核心执行入口方法 /// </summary> private void Execute() { //TODO 业务逻辑代码,如下模拟 Stopwatch stopwatch = Stopwatch.StartNew(); for (int i = 1; i <= 100; i++) { Console.WriteLine("test WriteLine:" + i); Thread.Sleep(100); } stopwatch.Stop(); logger.LogInformation("Logging - Execute Elapsed Times:{}ms", stopwatch.ElapsedMilliseconds); } } }

    因为要使用.NET CORE相关核心组件,故需要引用相关的NuGet包(引用包的方式有多种方式),而且默认的.NET CORE控制台只会生成DLL并不会生成EXE启动程序,故如果仅在WIN系统下使用,还需要设置生成方式等,详细配置属性如下:(项目文件csproj)

    <Project Sdk="Microsoft.NET.Sdk">
    
      <PropertyGroup>
        <OutputType>Exe</OutputType>
        <TargetFramework>netcoreapp2.2</TargetFramework>
        <RuntimeIdentifiers>win10-x64</RuntimeIdentifiers>
        <SelfContained>false</SelfContained>
      </PropertyGroup>
    
      <ItemGroup>
        <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="2.2.0" />
        <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="2.2.0" />
        <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="2.2.0" />
      </ItemGroup>
    
    </Project>
    View Code

     如上代码虽简单但代码编写顺序很关键,这里进行说明一下:

    1.因为一般应用程序都会有config文件,故我们需要先通过new ConfigurationBuilder来设置config文件的方式及路径;

    2.因为要使用.NET CORE默认的IOC框架,故new ServiceCollection,然后将相关的依赖服务组件注册到IOC容器中;

    3.config、logging 均是一个程序最基本的依赖组件,故将其注册到IOC容器中,注册logging有专门的扩展方法(AddLogging),而config没有则直接使用通过的注册方法(当然也可以基于ServiceCollection写一个AddConfiguration扩展方法)

    4.控制台需要一个核心的入口方法,用于处理核心业务,不要直接在Program中写方法,这样就不能使用IOC,同时也没有做到职责分明,Program仅是程序启动入口,业务处理应该有专门的入口,故上述代码中有HostService类(即:核心宿主服务类, 意为存在于控制台中的服务处理类,在这个类的构造涵数中列出所需依赖的服务组件,以便实例化时IOC可以自动注入这个参数),并注册到IOC容器中,当然也可以先定义一个IHostService接口然后实现这个接口。(如果有多个HostService类实例,建议定义一个IHostService接口,接口中只需要入口方法定义即可,如:RunAsync)

    5.当各组件初始化设置OK、IOC注册到位后,就应该通过IOC解析获得HostService类实例,并执行入口方法:RunAsync,该方法为异步后台执行,即调用该方法后,会在单独的后台线程处理核心业务,然后主线程继续往下面走,输出关闭提示信息,最后的Console.ReadLine();很关键,这个是等待输入流并挂起当前主线程,目的大家都知道,不要让控制台程序关闭。

     通过上述的讲解及源代码展示,有没有感觉优雅呢?如果觉得这样还算优雅,那下面展示的第二种更优雅的姿势

    编写.NET CORE控制台程序优雅姿势二:(使用通用主机也称泛型主机HostBuilder)

    代码如下:Program.cs

    using Microsoft.Extensions.DependencyInjection;
    using Microsoft.Extensions.Hosting;
    using Microsoft.Extensions.Logging;
    using NLog.Extensions.Logging;
    using Microsoft.Extensions.Configuration;
    using System.IO;
    using Polly;
    using System;
    
    namespace NetCoreConsoleApp
    {
        class Program
        {
            static void Main(string[] args)
            {
                var host = new HostBuilder()
                    .ConfigureHostConfiguration(configHost =>
                    {
                        configHost.SetBasePath(Directory.GetCurrentDirectory());
                    })
                    .ConfigureAppConfiguration(configApp =>
                    {
                        configApp.AddJsonFile("appsettings.json", optional: false, reloadOnChange: true);
                    })
                    .ConfigureServices((context, services) =>
                    {
                        //添加数据访问组件示例:services.AddTransient<IDbAccesser>(provider =>
                        //{
                        //    string connStr = context.Configuration.GetConnectionString("ConnDbStr");
                        //    return new SqlDapperEasyUtil(connStr);
                        //});
    
                        //添加HttpClient封装类示例:services.AddHttpClient<GitHubApiClient>()
                        //.AddTransientHttpErrorPolicy(builder => builder.WaitAndRetryAsync(3, t => TimeSpan.FromMilliseconds(800)));
    
                        services.AddHostedService<DemoHostedService>();
                    })
                    .ConfigureLogging((context, configLogging) =>
                    {
                        configLogging.ClearProviders();
                        configLogging.SetMinimumLevel(LogLevel.Trace);
                        configLogging.AddNLog(context.Configuration);
                    })
                    .UseConsoleLifetime()
                    .Build();
    
                host.Run();
            }
        }
    }
    

    DemoHostedService类代码:

    using Microsoft.Extensions.Configuration;
    using Microsoft.Extensions.Hosting;
    using Microsoft.Extensions.Logging;
    using System;
    using System.Diagnostics;
    using System.Threading;
    using System.Threading.Tasks;
    
    namespace NetCoreConsoleApp
    {
        public class DemoHostedService : IHostedService
        {
            private readonly IConfiguration config;
            private readonly ILogger logger;
    
            public DemoHostedService(IConfiguration config, ILogger<DemoHostedService> logger)
            {
                this.config = config;
                this.logger = logger;
            }
    
            public Task StartAsync(CancellationToken cancellationToken)
            {
                Console.WriteLine(nameof(DemoHostedService) + "已开始执行...");
    
                //TODO 业务逻辑代码,如下模拟
                Stopwatch stopwatch = Stopwatch.StartNew();
                for (int i = 1; i <= 100; i++)
                {
                    Console.WriteLine("test WriteLine:" + i);
                    Thread.Sleep(100);
                }
    
                stopwatch.Stop();
    
                logger.LogInformation("Logging - Execute Elapsed Times:{}ms", stopwatch.ElapsedMilliseconds);
    
                return Task.FromResult(0);
            }
    
            public Task StopAsync(CancellationToken cancellationToken)
            {
                Console.WriteLine(nameof(DemoHostedService) + "已被停止");
                return Task.FromResult(0);
            }
    
        }
    }
    

     

    因为要使用HostBuilder类及相关的.NET CORE组件(如上代码主要使用到了:Host、Dapper、Nlog、Polly等),故仍需引用相关的NuGet包,详细配置属性如下:(项目文件csproj)

    <Project Sdk="Microsoft.NET.Sdk">
    
      <PropertyGroup>
        <OutputType>Exe</OutputType>
        <TargetFramework>netcoreapp2.2</TargetFramework>
        <RuntimeIdentifiers>win10-x64</RuntimeIdentifiers>
        <SelfContained>false</SelfContained>
      </PropertyGroup>
    
      <ItemGroup>
        <PackageReference Include="Dapper" Version="1.60.6" />
        <PackageReference Include="Microsoft.Extensions.Configuration.FileExtensions" Version="2.2.0" />
        <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="2.2.0" />
        <PackageReference Include="Microsoft.Extensions.Hosting" Version="2.2.0" />
        <PackageReference Include="Microsoft.Extensions.Http.Polly" Version="2.2.0" />
        <PackageReference Include="NLog.Extensions.Logging" Version="1.5.1" />
        <PackageReference Include="System.Collections.Concurrent" Version="4.3.0" />
      </ItemGroup>
    
      <ItemGroup>
        <None Update="appsettings.json">
          <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
        </None>
        <None Update="nlog.config">
          <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
        </None>
      </ItemGroup>
    
    </Project>
    View Code

     如上代码所示,写过ASP.NET CORE程序的人可能比较眼熟,这与ASP.NET CORE的写法很类似,是的,你没有看错,HostBuilder是通用主机,是可以广泛应用于非HTTP的环境下,而ASP.NET CORE中的WebHostBuilder 主要用于HTTP WEB环境,使用方式基本类似,都是先定义HostBuilder,然后利用扩展方法注册、配置各种组件(中间件),最后调用Host的Run方法,开启后台服务执行,不同的是WebHostBuilder多了属于HTTP专有的一些属性及方法及其适用的中间件。

    由于这种写法比较通用,适用于已熟悉.NET CORE或ASP.NET CORE的人群,上手也较简单,故建议采取这种方式来写.NET CORE控制台程序。需要注意的是HostBuilder中最重要的是:注册HostedService 服务,如上代码中的DemoHostedService即是实现了IHostedService接口的宿主后台服务类,可以定义多个,然后都注册到IOC中,最后Host会按注册先后顺序执行多个HostedService服务的StartAsync方法,当停止时同样会执行多个HostedService服务的StopAsync方法

    下面再来看看使用Spring&Spring Boot框架来优雅的编写控制台程序 

    编写Spring控制台程序优雅姿势一:(只引用所必需的spring jar包、logger jar包,追求极简风)

    使用IDEA +MAVEN 创建一个quickstart 控制台项目,在maven POM XML中先引用所必需的spring jar包、logger jar包等,配置如下:

    <?xml version="1.0" encoding="UTF-8"?>
    
    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    
        <modelVersion>4.0.0</modelVersion>
    
        <artifactId>spring-console</artifactId>
    
        <name>spring-console</name>
        <!-- FIXME change it to the project's website -->
        <url>http://www.zuowenjun.cn</url>
    
        <properties>
            <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
            <maven.compiler.source>1.8</maven.compiler.source>
            <maven.compiler.target>1.8</maven.compiler.target>
            <spring.version>5.1.8.RELEASE</spring.version>
        </properties>
    
        <dependencies>
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>4.11</version>
                <scope>test</scope>
            </dependency>
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-core</artifactId>
                <version>${spring.version}</version>
            </dependency>
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-beans</artifactId>
                <version>${spring.version}</version>
            </dependency>
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-context</artifactId>
                <version>${spring.version}</version>
            </dependency>
            <dependency>
                <groupId>org.slf4j</groupId>
                <artifactId>slf4j-api</artifactId>
                <version>1.7.25</version>
            </dependency>
            <dependency>
                <groupId>ch.qos.logback</groupId>
                <artifactId>logback-classic</artifactId>
                <version>1.2.3</version>
            </dependency>
        </dependencies>
    
        <build>
            <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
                <plugins>
                    <!-- clean lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
                    <plugin>
                        <artifactId>maven-clean-plugin</artifactId>
                        <version>3.1.0</version>
                    </plugin>
                    <!-- default lifecycle, jar packaging: see https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
                    <plugin>
                        <artifactId>maven-resources-plugin</artifactId>
                        <version>3.0.2</version>
                    </plugin>
                    <plugin>
                        <artifactId>maven-compiler-plugin</artifactId>
                        <version>3.8.0</version>
                    </plugin>
                    <plugin>
                        <artifactId>maven-surefire-plugin</artifactId>
                        <version>2.22.1</version>
                    </plugin>
                    <plugin>
                        <artifactId>maven-jar-plugin</artifactId>
                        <version>3.0.2</version>
                    </plugin>
                    <plugin>
                        <artifactId>maven-install-plugin</artifactId>
                        <version>2.5.2</version>
                    </plugin>
                    <plugin>
                        <artifactId>maven-deploy-plugin</artifactId>
                        <version>2.8.2</version>
                    </plugin>
                    <!-- site lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#site_Lifecycle -->
                    <plugin>
                        <artifactId>maven-site-plugin</artifactId>
                        <version>3.7.1</version>
                    </plugin>
                    <plugin>
                        <artifactId>maven-project-info-reports-plugin</artifactId>
                        <version>3.0.0</version>
                    </plugin>
                </plugins>
            </pluginManagement>
            <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <configuration>
                        <source>8</source>
                        <target>8</target>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    </project>
    View Code

    然后采取自定义注解类(SpringBeansConfig)的方式注册相关Bean(包含配置映射类Bean:AppProperties),代码如下:

    //app.java
    
    package cn.zuowenjun.spring;
    
    import cn.zuowenjun.spring.cn.zuowenjun.spring.services.HostService;
    import org.springframework.context.annotation.AnnotationConfigApplicationContext;
    
    import java.io.IOException;
    
    /**
     * Hello world!
     */
    public class App {
        public static void main(String[] args) {
            AnnotationConfigApplicationContext applicationContext = new AnnotationConfigApplicationContext(SpringBeansConfig.class);
            HostService hostService = applicationContext.getBean(HostService.class);
    
            hostService.run();
    
            applicationContext.registerShutdownHook();
    
            try {
                System.in.read();
            } catch (IOException e) {
                System.out.println("等待读取输入数据报错:" + e.getMessage() + ",将直接退出程序!");
            }
        }
    }
    
    
    //AppProperties.java
    
    package cn.zuowenjun.spring;
    
    import org.springframework.beans.factory.annotation.Value;
    
    
    public class AppProperties {
    
        @Value("${app.name}")
        private String appName;
    
        @Value("${app.author}")
        private String appAuthor;
    
        @Value("${app.test.msg}")
        private String testMsg;
    
        public String getAppName() {
            return appName;
        }
    
        public void setAppName(String appName) {
            this.appName = appName;
        }
    
        public String getAppAuthor() {
            return appAuthor;
        }
    
        public void setAppAuthor(String appAuthor) {
            this.appAuthor = appAuthor;
        }
    
        public String getTestMsg() {
            return testMsg;
        }
    
        public void setTestMsg(String testMsg) {
            this.testMsg = testMsg;
        }
    }
    
    
    //SpringBeansConfig.java
    
    package cn.zuowenjun.spring;
    
    import cn.zuowenjun.spring.cn.zuowenjun.spring.services.HostService;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.context.annotation.PropertySource;
    import org.springframework.context.annotation.Scope;
    import org.springframework.core.annotation.Order;
    
    @Configuration
    @PropertySource(value = "classpath:app.properties", ignoreResourceNotFound = false)
    public class SpringBeansConfig {
    
        @Bean
        @Order(1)
        public HostService hostService() {
            return new HostService();
        }
    
        @Bean
        @Order(0)
        @Scope("singleton")
        public AppProperties appProperties() {
            return new AppProperties();
        }
    
        //注册其它所需Bean...
    }
    
    
    //HostService.java
    
    package cn.zuowenjun.spring.cn.zuowenjun.spring.services;
    
    import cn.zuowenjun.spring.AppProperties;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.util.StopWatch;
    
    import java.util.Collections;
    import java.util.concurrent.ExecutorService;
    import java.util.concurrent.Executors;
    
    
    public class HostService {
    
        private static final Logger LOGGER = LoggerFactory.getLogger(HostService.class);
    
        @Autowired
        private AppProperties appProperties;
    
        //可以添加其它属性注入
    
        public void run() {
    //        ExecutorService pool = Executors.newSingleThreadExecutor();
    //        pool.execute(() -> execute());
    
            new Thread(this::execute).start();
        }
    
        /// <summary>
        /// 控制台核心执行入口方法
        /// </summary>
        private void execute() {
            //TODO 业务逻辑代码,如下模拟
            StopWatch stopwatch = new StopWatch();
            stopwatch.start();
            for (int i = 1; i <= 100; i++) {
                System.out.println("test WriteLine:" + i);
                try {
                    Thread.sleep(100);
                } catch (Exception e) {
                }
            }
            stopwatch.stop();
    
            System.out.println(String.join("", Collections.nCopies(30, "=")));
    
            System.out.printf("app name is:%s %n", appProperties.getAppName());
            System.out.printf("app author is:%s %n", appProperties.getAppAuthor());
            System.out.printf("app test msg:%s %n", appProperties.getTestMsg());
    
            LOGGER.info("Logging - Execute Elapsed Times:{}ms", stopwatch.getTotalTimeMillis());
        }
    }
    

     app.properties配置文件内容如下,注意应放在classpth目录下(即:resources目录下,没有需自行创建并设为resources目录):

    app.name=demo spring console
    app.author=zuowenjun
    app.test.msg=hello java spring console app!
    

     如上即上实现一个spring的控制台程序,当然由于是示例,故只引用了logger包,正常还需引用jdbc或ORM框架的相关jar包, 上述代码关键逻辑说明(同样要注意顺序):

    1.new AnnotationConfigApplicationContext类(spring IOC容器),创建一个IOC容器,类似.NET CORE中的ServiceProvider类;

    2.定义 SpringBeansConfig bean注册配置类(注册相关依赖),这个类中依次注入相关的bean,如果bean之间有依赖顺序关系,建议添加@Order并指明序号;该类作为AnnotationConfigApplicationContext的构造函数参数传入,以便IOC自动解析并完成实际注册;

    3.同样是定义一个HostService 宿主服务类,并实现run方法逻辑,一般采取后台线程异步执行,为了演示效果与.NET CORE的HostService 类相同,示例逻辑基本相同。另外还定义了AppProperties配置映射类,便于直接读取配置,.NET CORE同样也有类似注册bind到配置类中,然后在服务类中使用:IOptions<配置类>作为构造函数参数实现构造函数注入。只是由于篇幅有限故.NET CORE部份直接采取了注入IConfiguration,大家有兴趣可以查看网上相关资料。

    4.IOC容器初始化并注册成功后,即可解析HostService 类获得实例,执行run方法,run方法会开启线程在后台处理,并返回到主线程,直至in.read()阻塞挂起主线程,防止程序自动关闭。

    编写Spring boot控制台程序优雅姿势二:(引用spring boot jar包)

     使用IDEA+Spring Initializr来创建一个spring boot项目,创建过程中按需选择依赖的框架,我这里是示例,故除了默认spring-boot-starter依赖外,其余什么依赖都不添加,创建后Maven POM XML如下:

    <?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
        <modelVersion>4.0.0</modelVersion>
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.1.6.RELEASE</version>
            <relativePath/> <!-- lookup parent from repository -->
        </parent>
        <groupId>cn.zuowenjun.spring</groupId>
        <artifactId>springboot-console</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>springboot-console</name>
        <description>Demo project for Spring Boot</description>
        <url>http://www.zuowenjun.cn</url>
    
        <properties>
            <java.version>1.8</java.version>
        </properties>
    
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </dependency>
        </dependencies>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
            </plugins>
        </build>
    
    </project>
    View Code

    然后创建相关的Bean类:HostService(宿主服务类,这个与前文定义类均相同)、AppProperties(配置映射类,这个是映射默认的application.properties配置文件,注意这里的映射方式与前文所描述稍有不周,采用:@ConfigurationProperties+属性映射,无需加@Value注解,映射属性时如果有-则应写成驼峰式,如果有.则应定义内部静态类,呈现层级属性完成映射,具体的用法可以参见我之前的文章):

    //HostService.java
    
    package cn.zuowenjun.spring.services;
    
    import cn.zuowenjun.spring.AppProperties;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Component;
    import org.springframework.util.StopWatch;
    
    import java.util.Collections;
    
    @Component
    public class HostService {
    
        private static final Logger LOGGER = LoggerFactory.getLogger(HostService.class);
    
        @Autowired
        private AppProperties appProperties;
    
        //可以添加其它属性注入
    
        public void run() {
    //        ExecutorService pool = Executors.newSingleThreadExecutor();
    //        pool.execute(() -> execute());
    
            new Thread(this::execute).start();
        }
    
        /// <summary>
        /// 控制台核心执行入口方法
        /// </summary>
        private void execute() {
            //TODO 业务逻辑代码,如下模拟
            StopWatch stopwatch = new StopWatch();
            stopwatch.start();
            for (int i = 1; i <= 100; i++) {
                System.out.println("test WriteLine:" + i);
                try {
                    Thread.sleep(100);
                } catch (Exception e) {
                }
            }
            stopwatch.stop();
    
            System.out.println(String.join("", Collections.nCopies(30, "=")));
    
            System.out.printf("app name is:%s %n", appProperties.getName());
            System.out.printf("app author is:%s %n", appProperties.getAuthor());
            System.out.printf("app test msg:%s %n", appProperties.getTestMsg());
    
            LOGGER.info("Logging - Execute Elapsed Times:{}ms", stopwatch.getTotalTimeMillis());
        }
    }
    
    
    //AppProperties.java
    
    package cn.zuowenjun.spring;
    
    import org.springframework.boot.context.properties.ConfigurationProperties;
    import org.springframework.stereotype.Component;
    
    @Component
    @ConfigurationProperties(prefix = "app")
    public class AppProperties {
    
        private String name;
    
        private String author;
    
        private String testMsg;
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public String getAuthor() {
            return author;
        }
    
        public void setAuthor(String author) {
            this.author = author;
        }
    
        public String getTestMsg() {
            return testMsg;
        }
    
        public void setTestMsg(String testMsg) {
            this.testMsg = testMsg;
        }
    }
    

    application.properties配置文件:(注意app.test.msg此处改为了app.test-msg,因为这样就可以直接映射到类的属性中,否则得定义内部类有点麻烦)

    app.name=demo spring console
    app.author=zuowenjun
    app.test-msg=hello java spring console app!

     最后改造spring boot application类,让SpringbootConsoleApplication类实现ApplicationRunner接口,并在run方法中编写通过属性依赖注入获得HostService类的实例,最后执行HostService的run方法即可,代码如下:

    package cn.zuowenjun.spring;
    
    import cn.zuowenjun.spring.services.HostService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.boot.ApplicationArguments;
    import org.springframework.boot.ApplicationRunner;
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    public class SpringbootConsoleApplication implements ApplicationRunner {
    
        @Autowired
        private HostService hostService;
    
        public static void main(String[] args) {
            SpringApplication.run(SpringbootConsoleApplication.class, args);
        }
    
        @Override
        public void run(ApplicationArguments args) throws Exception {
            hostService.run();
        }
    }
    

     如上步骤即完成了优雅编写spring boot控制台程序,关键点是ApplicationRunner,这个是给spring boot执行的入口,另一种思路,我们其实还可以把HostService类改造一下,让其实现ApplicationRunner接口,那么run方法即为spring boot的启动入口。

    总结一下:.

    NET CORE控制台程序优雅姿势一与Spring控制台优雅姿势一核心思想是一样的,都是手动创建各个依赖组件及IOC容器的实例,都是通过IOC容器显式的解析获得HostService类的实例,最后运行HostService#run方法。

    NET CORE控制台程序优雅姿势二与Spring控制台优雅姿势二核心思想也是一样的,都是利用IOC容器来直接管理注册的各个依赖组件,并由.NET CORE、Spring boot框架自行调度HostService#run方法。

    我个人更倾向优雅姿势二的方法来编写.NET CORE或Spring Boot的控制台程序,因为写得更少,做得更多。

     

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  • 原文地址:https://www.cnblogs.com/zuowj/p/11107243.html
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