草庐IT

java - Spring Boot - 无法确定数据库类型 NONE 的嵌入式数据库驱动程序类

coder 2023-04-26 原文

这是尝试运行我的网络应用程序时引发的错误:

[INFO] WARNING: Nested in org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private javax.sql.DataSource org.springframework.boot.autoconfigure.orm.jpa.JpaBaseConfiguration.dataSource; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfiguration$NonEmbeddedConfiguration.class]: Instantiation of bean failed; nested exception is org.springframework.beans.factory.BeanDefinitionStoreException: Factory method [public javax.sql.DataSource org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration$NonEmbeddedConfiguration.dataSource()] threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Cannot determine embedded database driver class for database type NONE. If you want an embedded database please put a supported one on the classpath.:
    [INFO] org.springframework.beans.factory.BeanCreationException: Cannot determine embedded database driver class for database type NONE. If you want an embedded database please put a supported one on the classpath.
    [INFO]  at org.springframework.boot.autoconfigure.jdbc.DataSourceProperties.getDriverClassName(DataSourceProperties.java:91)
    [INFO]  at org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration$NonEmbeddedConfiguration.dataSource(DataSourceAutoConfiguration.java:100)
    [INFO]  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    [INFO]  at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    [INFO]  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    [INFO]  at java.lang.reflect.Method.invoke(Method.java:606)
    [INFO]  at com.google.appengine.tools.development.agent.runtime.Runtime.invoke(Runtime.java:115)
    [INFO]  at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:166)
    [INFO]  at org.springframework.beans.factory.support.ConstructorResolver$3.run(ConstructorResolver.java:580)
    [INFO]  at java.security.AccessController.doPrivileged(Native Method)
    [INFO]  at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:577)
    [INFO]  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1094)
    [INFO]  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:989)
    [INFO]  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
    [INFO]  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
    [INFO]  at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
    [INFO]  at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
    [INFO]  at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
    [INFO]  at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
    [INFO]  at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1017)
    [INFO]  at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:960)
    [INFO]  at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:858)
    [INFO]  at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:480)
    [INFO]  at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:87)
    [INFO]  at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:289)
    [INFO]  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1185)
    [INFO]  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
    [INFO]  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
    [INFO]  at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
    [INFO]  at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
    [INFO]  at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
    [INFO]  at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
    [INFO]  at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:370)
    [INFO]  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1094)
    [INFO]  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:989)
    [INFO]  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
    [INFO]  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
    [INFO]  at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
    [INFO]  at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
    [INFO]  at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
    [INFO]  at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
    [INFO]  at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:973)
    [INFO]  at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:750)
    [INFO]  at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    [INFO]  at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:683)
    [INFO]  at org.springframework.boot.SpringApplication.run(SpringApplication.java:313)
    [INFO]  at org.springframework.boot.builder.SpringApplicationBuilder.run(SpringApplicationBuilder.java:142)
    [INFO]  at org.springframework.boot.legacy.context.web.SpringBootContextLoaderListener.initWebApplicationContext(SpringBootContextLoaderListener.java:60)
    [INFO]  at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106)
    [INFO]  at org.mortbay.jetty.handler.ContextHandler.startContext(ContextHandler.java:548)
    [INFO]  at org.mortbay.jetty.servlet.Context.startContext(Context.java:136)
    [INFO]  at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1250)
    [INFO]  at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:517)
    [INFO]  at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:467)
    [INFO]  at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
    [INFO]  at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    [INFO]  at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
    [INFO]  at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    [INFO]  at org.mortbay.jetty.Server.doStart(Server.java:224)
    [INFO]  at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
    [INFO]  at com.google.appengine.tools.development.JettyContainerService.startContainer(JettyContainerService.java:249)
    [INFO]  at com.google.appengine.tools.development.AbstractContainerService.startup(AbstractContainerService.java:306)
    [INFO]  at com.google.appengine.tools.development.AutomaticInstanceHolder.startUp(AutomaticInstanceHolder.java:26)
    [INFO]  at com.google.appengine.tools.development.AbstractModule.startup(AbstractModule.java:79)
    [INFO]  at com.google.appengine.tools.development.Modules.startup(Modules.java:88)
    [INFO]  at com.google.appengine.tools.development.DevAppServerImpl.doStart(DevAppServerImpl.java:254)
    [INFO]  at com.google.appengine.tools.development.DevAppServerImpl.access$000(DevAppServerImpl.java:47)
    [INFO]  at com.google.appengine.tools.development.DevAppServerImpl$1.run(DevAppServerImpl.java:212)
    [INFO]  at com.google.appengine.tools.development.DevAppServerImpl$1.run(DevAppServerImpl.java:210)
    [INFO]  at java.security.AccessController.doPrivileged(Native Method)
    [INFO]  at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerImpl.java:210)
    [INFO]  at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:277)
    [INFO]  at com.google.appengine.tools.util.Parser$ParseResult.applyArgs(Parser.java:48)
    [INFO]  at com.google.appengine.tools.development.DevAppServerMain.run(DevAppServerMain.java:219)
    [INFO]  at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMain.java:210)

我相信我有正确的 datanucleus-appenginedatanucleus jar 组合:

2.1: Requires DataNucleus 3.1.x (core, api-jdo, api-jpa, enhancer). Requires SDK 1.6.4+ Note that this release of Datanucleus is no longer supported by the DataNucleus project

JPA 应用配置:

@Configuration
@EnableJpaRepositories("demo.core.entity")
@EnableTransactionManagement
class JpaApplicationConfig {
    private static final Logger logger = Logger
            .getLogger(JpaApplicationConfig.class.getName());
    @Bean
    public AbstractEntityManagerFactoryBean entityManagerFactory() {
        logger.info("Loading Entity Manager...");
        LocalContainerEntityManagerFactoryBean factory = new LocalContainerEntityManagerFactoryBean();
        factory.setPersistenceUnitName("transactions-optional");
        return factory;
    }
    @Bean
    public PlatformTransactionManager transactionManager() {
        logger.info("Loading Transaction Manager...");
        JpaTransactionManager txManager = new JpaTransactionManager();
        txManager.setEntityManagerFactory(entityManagerFactory().getObject());
        return txManager;
    }
    @Bean
    public PersistenceExceptionTranslator persistenceExceptionTranslator() {
        return new OpenJpaDialect();
    }
}

Application.java

@Configuration
@ComponentScan
@EnableAutoConfiguration
@RestController
public class Application {

    private static final EntityManagerFactory INSTANCE =
            Persistence.createEntityManagerFactory("transactions-optional");

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @RequestMapping("/")
    public String home() {
        return "Hello World";
    }

}

POM:

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="...">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.demohq</groupId>
    <artifactId>demo-boot</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>

    <name>demo-boot</name>
    <description>Demo project</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.1.0.BUILD-SNAPSHOT</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-legacy</artifactId>
            <version>1.1.0.BUILD-SNAPSHOT</version>
        </dependency>
        <!--<dependency>-->
            <!--<groupId>net.kindleit</groupId>-->
            <!--<artifactId>gae-runtime</artifactId>-->
            <!--<version>${gae.version}</version>-->
            <!--<type>pom</type>-->
            <!--<scope>provided</scope>-->
        <!--</dependency>-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aspects</artifactId>
        </dependency>
        <!--<dependency>-->
            <!--<groupId>org.hsqldb</groupId>-->
            <!--<artifactId>hsqldb</artifactId>-->
            <!--<scope>runtime</scope>-->
        <!--</dependency>-->
        <dependency>
            <groupId>com.google.appengine</groupId>
            <artifactId>appengine-api-labs</artifactId>
            <version>${gae.version}</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.google.appengine</groupId>
            <artifactId>appengine-api-stubs</artifactId>
            <version>${gae.version}</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.google.appengine</groupId>
            <artifactId>appengine-testing</artifactId>
            <version>${gae.version}</version>
            <scope>test</scope>
        </dependency>
        <!-- DataNucleus -->
        <dependency>
            <groupId>org.datanucleus</groupId>
            <artifactId>datanucleus-api-jpa</artifactId>
            <version>${datanucleus.jpa.version}</version>
        </dependency>
        <dependency>
            <groupId>org.datanucleus</groupId>
            <artifactId>datanucleus-core</artifactId>
            <version>${datanucleus.jpa.version}</version>
        </dependency>
        <dependency>
            <groupId>org.datanucleus</groupId>
            <artifactId>datanucleus-enhancer</artifactId>
            <version>${datanucleus.jpa.version}</version>
        </dependency>
        <dependency>
            <groupId>com.google.appengine.orm</groupId>
            <artifactId>datanucleus-appengine</artifactId>
            <version>${datanucleus.version}</version>
            <!-- Need to exclude the enhancer since it interfere with the enhancer plugin. -->
            <exclusions>
                <exclusion>
                    <groupId>org.datanucleus</groupId>
                    <artifactId>datanucleus-enhancer</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>javax.jdo</groupId>
            <artifactId>jdo-api</artifactId>
            <version>3.0.1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.geronimo.specs</groupId>
            <artifactId>geronimo-jpa_2.0_spec</artifactId>
            <version>1.1</version>
        </dependency>

        <!-- OpenJPA -->
        <dependency>
            <groupId>org.apache.openjpa</groupId>
            <artifactId>openjpa-persistence</artifactId>
            <version>2.3.0</version>
        </dependency>


    </dependencies>

    <properties>
        <start-class>demo.Application</start-class>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.7</java.version>
        <m2eclipse.wtp.contextRoot>/</m2eclipse.wtp.contextRoot>
        <datanucleus.jpa.version>3.1.1</datanucleus.jpa.version>
        <datanucleus.version>2.1.2</datanucleus.version>
        <gae.version>1.8.8</gae.version>
        <gae.home>${settings.localRepository}/com/google/appengine/appengine-java-sdk/${gae.version}/appengine-java-sdk/appengine-java-sdk-${gae.version}</gae.home>
        <gae.application.version>test</gae.application.version>
        <!--<org.springframework-version>4.0.5.RELEASE</org.springframework-version>-->
    </properties>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
            <!--
            <plugin>
                <groupId>net.kindleit</groupId>
                <artifactId>maven-gae-plugin</artifactId>
                <version>0.9.6</version>
                <dependencies>
                    <dependency>
                        <groupId>net.kindleit</groupId>
                        <artifactId>gae-runtime</artifactId>
                        <version>${gae.version}</version>
                        <type>pom</type>
                    </dependency>
                </dependencies>
            </plugin>
            -->
            <plugin>
                <groupId>com.google.appengine</groupId>
                <artifactId>appengine-maven-plugin</artifactId>
                <version>${gae.version}</version>
                <configuration>
                    <enableJarClasses>false</enableJarClasses>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-release-plugin</artifactId>
                <configuration>
                    <goals>gae:deploy</goals>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.tomcat.maven</groupId>
                <artifactId>tomcat6-maven-plugin</artifactId>
                <version>2.0</version>
                <configuration>
                    <path>/</path>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.datanucleus</groupId>
                <artifactId>maven-datanucleus-plugin</artifactId>
                <version>${datanucleus.jpa.version}</version>
                <configuration>
                    <api>JPA</api>
                    <!--<mappingIncludes>**/entity/*.class</mappingIncludes>-->
                    <verbose>true</verbose>
                </configuration>
                <dependencies>
                    <dependency>
                        <groupId>org.datanucleus</groupId>
                        <artifactId>datanucleus-core</artifactId>
                        <version>${datanucleus.jpa.version}</version>
                    </dependency>
                </dependencies>
                <executions>
                    <execution>
                        <phase>compile</phase>
                        <goals>
                            <goal>enhance</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

    <profiles>
        <!-- We can configure our integration server to activate this profile and 
            perform gae:deploy, thus uploading latest snapshot to the http://1.latest.<applicationName>.appspot.com 
            automatically -->
        <profile>
            <id>integration-build</id>
            <properties>
                <gae.application.version>stage</gae.application.version>
            </properties>
        </profile>

        <!-- This profile will activate automatically during release and upload 
            application to the http://2.latest.<applicationName>.appspot.com (We might 
            want to set the 2nd version as our applications Default version to be accessible 
            at http://<applicationName>.appspot.com) -->
        <profile>
            <id>release-build</id>
            <activation>
                <property>
                    <name>performRelease</name>
                    <value>true</value>
                </property>
            </activation>

            <properties>
                <!-- During release, set application version in appengine-web.xml to 
                    2 -->
                <gae.application.version>release</gae.application.version>
            </properties>
        </profile>
    </profiles>

    <repositories>
        <repository>
            <id>spring-snapshots</id>
            <name>Spring Snapshots</name>
            <url>http://repo.spring.io/snapshot</url>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </repository>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>http://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>
    <pluginRepositories>
        <pluginRepository>
            <id>spring-snapshots</id>
            <name>Spring Snapshots</name>
            <url>http://repo.spring.io/snapshot</url>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </pluginRepository>
        <pluginRepository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>http://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </pluginRepository>
    </pluginRepositories>

</project>

我想知道我的应用中可能缺少什么?我按照这里的说明 Using Spring Data JPA on Google Appengine

最佳答案

您没有为 Spring Boot 提供足够的信息来自动配置 DataSource。为此,您需要使用 spring.datasource 前缀向 application.properties 添加一些属性。看看DataSourceProperties查看您可以设置的所有属性。

您需要提供适当的 url 和驱动程序类名称:

spring.datasource.url = …
spring.datasource.driver-class-name = …

关于java - Spring Boot - 无法确定数据库类型 NONE 的嵌入式数据库驱动程序类,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/24074749/

有关java - Spring Boot - 无法确定数据库类型 NONE 的嵌入式数据库驱动程序类的更多相关文章

  1. ruby - 在 Ruby 程序执行时阻止 Windows 7 PC 进入休眠状态 - 2

    我需要在客户计算机上运行Ruby应用程序。通常需要几天才能完成(复制大备份文件)。问题是如果启用sleep,它会中断应用程序。否则,计算机将持续运行数周,直到我下次访问为止。有什么方法可以防止执行期间休眠并让Windows在执行后休眠吗?欢迎任何疯狂的想法;-) 最佳答案 Here建议使用SetThreadExecutionStateWinAPI函数,使应用程序能够通知系统它正在使用中,从而防止系统在应用程序运行时进入休眠状态或关闭显示。像这样的东西:require'Win32API'ES_AWAYMODE_REQUIRED=0x0

  2. ruby - 解析 RDFa、微数据等的最佳方式是什么,使用统一的模式/词汇(例如 schema.org)存储和显示信息 - 2

    我主要使用Ruby来执行此操作,但到目前为止我的攻击计划如下:使用gemsrdf、rdf-rdfa和rdf-microdata或mida来解析给定任何URI的数据。我认为最好映射到像schema.org这样的统一模式,例如使用这个yaml文件,它试图描述数据词汇表和opengraph到schema.org之间的转换:#SchemaXtoschema.orgconversion#data-vocabularyDV:name:namestreet-address:streetAddressregion:addressRegionlocality:addressLocalityphoto:i

  3. ruby - 如何指定 Rack 处理程序 - 2

    Rackup通过Rack的默认处理程序成功运行任何Rack应用程序。例如:classRackAppdefcall(environment)['200',{'Content-Type'=>'text/html'},["Helloworld"]]endendrunRackApp.new但是当最后一行更改为使用Rack的内置CGI处理程序时,rackup给出“NoMethodErrorat/undefinedmethod`call'fornil:NilClass”:Rack::Handler::CGI.runRackApp.newRack的其他内置处理程序也提出了同样的反对意见。例如Rack

  4. ruby - 在 Ruby 中编写命令行实用程序 - 2

    我想用ruby​​编写一个小的命令行实用程序并将其作为gem分发。我知道安装后,Guard、Sass和Thor等某些gem可以从命令行自行运行。为了让gem像二进制文件一样可用,我需要在我的gemspec中指定什么。 最佳答案 Gem::Specification.newdo|s|...s.executable='name_of_executable'...endhttp://docs.rubygems.org/read/chapter/20 关于ruby-在Ruby中编写命令行实用程序

  5. ruby-on-rails - Rails 应用程序之间的通信 - 2

    我构建了两个需要相互通信和发送文件的Rails应用程序。例如,一个Rails应用程序会发送请求以查看其他应用程序数据库中的表。然后另一个应用程序将呈现该表的json并将其发回。我还希望一个应用程序将存储在其公共(public)目录中的文本文件发送到另一个应用程序的公共(public)目录。我从来没有做过这样的事情,所以我什至不知道从哪里开始。任何帮助,将不胜感激。谢谢! 最佳答案 无论Rails是什么,几乎所有Web应用程序都有您的要求,大多数现代Web应用程序都需要相互通信。但是有一个小小的理解需要你坚持下去,网站不应直接访问彼此

  6. ruby - 无法运行 Rails 2.x 应用程序 - 2

    我尝试运行2.x应用程序。我使用rvm并为此应用程序设置其他版本的ruby​​:$rvmuseree-1.8.7-head我尝试运行服务器,然后出现很多错误:$script/serverNOTE:Gem.source_indexisdeprecated,useSpecification.Itwillberemovedonorafter2011-11-01.Gem.source_indexcalledfrom/Users/serg/rails_projects_terminal/work_proj/spohelp/config/../vendor/rails/railties/lib/r

  7. ruby-on-rails - Rails 应用程序中的 Rails : How are you using application_controller. rb 是新手吗? - 2

    刚入门rails,开始慢慢理解。有人可以解释或给我一些关于在application_controller中编码的好处或时间和原因的想法吗?有哪些用例。您如何为Rails应用程序使用应用程序Controller?我不想在那里放太多代码,因为据我了解,每个请求都会调用此Controller。这是真的? 最佳答案 ApplicationController实际上是您应用程序中的每个其他Controller都将从中继承的类(尽管这不是强制性的)。我同意不要用太多代码弄乱它并保持干净整洁的态度,尽管在某些情况下ApplicationContr

  8. java - 等价于 Java 中的 Ruby Hash - 2

    我真的很习惯使用Ruby编写以下代码:my_hash={}my_hash['test']=1Java中对应的数据结构是什么? 最佳答案 HashMapmap=newHashMap();map.put("test",1);我假设? 关于java-等价于Java中的RubyHash,我们在StackOverflow上找到一个类似的问题: https://stackoverflow.com/questions/22737685/

  9. ruby-on-rails - 如何在我的 Rails 应用程序 View 中打印 ruby​​ 变量的内容? - 2

    我是一个Rails初学者,但我想从我的RailsView(html.haml文件)中查看Ruby变量的内容。我试图在ruby​​中打印出变量(认为它会在终端中出现),但没有得到任何结果。有什么建议吗?我知道Rails调试器,但更喜欢使用inspect来打印我的变量。 最佳答案 您可以在View中使用puts方法将信息输出到服务器控制台。您应该能够在View中的任何位置使用Haml执行以下操作:-puts@my_variable.inspect 关于ruby-on-rails-如何在我的R

  10. ruby - Ruby 有 `Pair` 数据类型吗? - 2

    有时我需要处理键/值数据。我不喜欢使用数组,因为它们在大小上没有限制(很容易不小心添加超过2个项目,而且您最终需要稍后验证大小)。此外,0和1的索引变成了魔数(MagicNumber),并且在传达含义方面做得很差(“当我说0时,我的意思是head...”)。散列也不合适,因为可能会不小心添加额外的条目。我写了下面的类来解决这个问题:classPairattr_accessor:head,:taildefinitialize(h,t)@head,@tail=h,tendend它工作得很好并且解决了问题,但我很想知道:Ruby标准库是否已经带有这样一个类? 最佳

随机推荐