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我是 SPRING 的初学者，我遇到了这个错误 Configuration question: Unable to locate Spring NamespaceHandler for XML schema namespace

我的 spring-app-context.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:p="http://www.springframework.org/schema/p"
       xmlns:http="http://www.springframework.org/schema/c"

       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="provider" class="com.alex.sp.HelloWorldMessageProvider"/>

    <bean id="renderer" class="com.alex.sp.StandardOutMessageRenderer"
          p:messageProvider-ref="provider"/>

StandardOutMessageRenderer.java

package com.alex.sp;

import com.alex.sp.Interface.MessageProvider;
import com.alex.sp.Interface.MessageRenderer;

public class StandardOutMessageRenderer implements MessageRenderer {

    private MessageProvider messageProvider;

    public StandardOutMessageRenderer(){
        System.out.println(" --> StandardOutMessageRenderer: constructor called");
    }

    @Override
    public void render() {
        if (messageProvider == null) {
            throw new RuntimeException(
                    "You must set the property messageProvider of class:"
                            + StandardOutMessageRenderer.class.getName());
        }
        System.out.println(messageProvider.getMessage());
    }

    @Override
    public void setMessageProvider(MessageProvider provider) {
        System.out.println(" --> StandardOutMessageRenderer: setting the provider");
        this.messageProvider = provider;
    }

    @Override
    public MessageProvider getMessageProvider() {
        return this.messageProvider;
    }
}

我的主要课程

import com.alex.sp.HelloWorldConfiguration;
import com.alex.sp.Interface.MessageRenderer;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class HelloSpringDI {

    public static  void main(String... args){
        ApplicationContext ctx = new
                ClassPathXmlApplicationContext("spring-app-context.xml");
         //       AnnotationConfigApplicationContext(HelloWorldConfiguration.class);

        MessageRenderer renderer = ctx.getBean("renderer", MessageRenderer.class );
        renderer.render();
    }
}

我的 pom.xml 文件

<?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>

    <groupId>gl2</groupId>
    <artifactId>gl2</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.version>1.8</maven.compiler.version>
        <classpathentry path="src/main/resources" kind="src" />
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>5.2.2.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.2.2.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context-support</artifactId>
            <version>5.2.2.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>5.2.2.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jcl</artifactId>
            <version>5.2.2.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-expression</artifactId>
            <version>5.2.2.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aop</artifactId>
            <version>5.2.2.RELEASE</version>
        </dependency>

    </dependencies>


    <build>
        <pluginManagement>
            <plugins>

                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <version>3.6.1</version>
                    <configuration>
                        <source>${maven.compiler.version}</source>
                        <target>${maven.compiler.version}</target>
                    </configuration>
                </plugin>

                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-shade-plugin</artifactId>
                    <version>3.2.1</version>
                    <executions>
                        <execution>
                            <phase>package</phase>
                            <goals><goal>shade</goal></goals>
                            <configuration>
                                <transformers>
                                    <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                                        <mainClass>HelloSpringDI</mainClass>
                                    </transformer>
                                    <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                                        <resource>spring-app-context.xml</resource>
                                    </transformer>

                                </transformers>
                            </configuration>
                        </execution>
                    </executions>
                </plugin>

 <!--               <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-assembly-plugin</artifactId>
                    <version>3.2.0</version>
                    <configuration>
                        <archive>
                            <manifest>
                                <mainClass>HelloSpringDI</mainClass>
                            </manifest>
                        </archive>
                        <descriptorRefs>
                            <descriptorRef>jar-with-dependencies</descriptorRef>
                        </descriptorRefs>
                    </configuration>
                    <executions>
                        <execution>
                            <id>make-assembly</id>
                            <phase>package</phase>
                            <goals>
                                <goal>single</goal>
                            </goals>
                        </execution>
                    </executions>
                </plugin>
-->
            </plugins>
        </pluginManagement>

        <plugins> <!-- did NOT work without this  -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
            </plugin>
        </plugins>



    </build>


</project>

示例在 intelliJ IDEA 中工作，但是当我制作 jar 并运行 mvn clean package java -jar ./target/gl2-1.0-SNAPSHOT.jar 时出现异常：

Exception in thread "main" org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: Unable to locate Spring NamespaceHandler for XML schema namespace [http://www.springframework.org/schema/p]
Offending resource: class path resource [spring-app-context.xml]

        at org.springframework.beans.factory.parsing.FailFastProblemReporter.error(FailFastProblemReporter.java:72)
        at org.springframework.beans.factory.parsing.ReaderContext.error(ReaderContext.java:119)
        at org.springframework.beans.factory.parsing.ReaderContext.error(ReaderContext.java:111)
        at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.error(BeanDefinitionParserDelegate.java:274)
        at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.decorateIfRequired(BeanDefinitionParserDelegate.java:1456)
        at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.decorateBeanDefinitionIfRequired(BeanDefinitionParserDelegate.java:1420)
        at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.decorateBeanDefinitionIfRequired(BeanDefinitionParserDelegate.java:1401)
        at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.processBeanDefinition(DefaultBeanDefinitionDocumentReader.java:308)
        at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.parseDefaultElement(DefaultBeanDefinitionDocumentReader.java:197)
        at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.parseBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:176)
        at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.doRegisterBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:149)
        at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.registerBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:96)
        at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.registerBeanDefinitions(XmlBeanDefinitionReader.java:514)
        at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:394)
        at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:337)
        at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:305)
        at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:188)
        at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:224)
        at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:195)
        at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:257)
        at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:128)
        at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:94)
        at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:133)
        at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:637)
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:522)
        at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:144)
        at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:85)
        at HelloSpringDI.main(HelloSpringDI.java:12)
4

1 回答 1

0

springframework 不存在模式 p。如果您查看 https://www.springframework.org/schema/，您会看到所有可用的模式。如果我正确理解您的代码，那么您只需将 HelloWorldMessageProvider 类的实例设置为 StandardOutMessageRenderer 类的对象。然后你不需要定义额外的弹簧模式。然后你可以使用setter注入 <bean id="renderer" class="com.alex.sp.StandardOutMessageRenderer"> <property name="provider" ref="provider"/> </bean>

查看https://www.springbyexample.org/examples/intro-to-ioc-basic-setter-injection.html以获得解释。

于 2020-01-05T13:36:55.937 回答