当我使用 -Djavax.xml.catalog.files=file://localhost/C:/path/to/Xml/catalog.xml 使用自定义 XML 目录时，我无法启动 Spring 5.3.10 应用程序。Spring 似乎没有为目录提供足够的信息来查找 URL。我可以使用在 Tomcat 中运行的 Spring 使用 WebMvc 并使用 Spring Boot 来重现这一点。
重现此问题的最简单方法是使用 STS 4 向导和以下非常简单的 Spring Boot 应用程序创建新的 Spring Boot 应用程序：
package com.example.demo;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ImportResource;
@SpringBootApplication
@ImportResource("classpath:beans.xml")
public class DemoApplication implements CommandLineRunner {
private String message;
@Autowired
@Qualifier("message")
public void setMessage(String message) {
this.message = message;
}
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
System.out.println("Exiting");
}
@Override
public void run(String... args) throws Exception {
System.out.println(message + " ma, I'm running");
}
}
beans.xml 文件非常简单，它只是制作 id 为 "message" 的 bean 并在其中放入一个字符串：
<?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:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
">
<bean id="message" class="java.lang.String">
<constructor-arg value="Hello" />
</bean>
</beans>
应用程序在没有 XML 目录的情况下可以正常工作，但是只要我使用 -Djavax.xml.catalog.files=file://localhost/C:/path/to/Xml/catalog.xml 启动应用程序，那么 Spring 就可以了t 从以下错误开始（我也有 -Djaxp.debug=99）：
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.5.6)
2021-11-03 13:04:28.909 INFO 17524 --- [ main] com.example.demo.DemoApplication : Starting DemoApplication using Java 11.0.2-redhat on ESDD-65912 with PID 17524 (C:\sts_workspace\sp121_EmailAssistant\demo\target\classes started by tperry2 in C:\sts_workspace\sp121_EmailAssistant\demo)
2021-11-03 13:04:28.910 INFO 17524 --- [ main] com.example.demo.DemoApplication : The following profiles are active: Development
JAXP: find factoryId =javax.xml.parsers.DocumentBuilderFactory
JAXP: loaded from fallback value: com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderFactoryImpl
JAXP: created new instance of class com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderFactoryImpl using ClassLoader: null
2021-11-03 13:04:29.172 WARN 17524 --- [ main] s.c.a.AnnotationConfigApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanDefinitionStoreException: Unexpected exception parsing XML document from class path resource [beans.xml]; nested exception is java.lang.NullPointerException: JAXP09020006: The argument 'systemId' can not be null.
2021-11-03 13:04:29.181 INFO 17524 --- [ main] ConditionEvaluationReportLoggingListener :
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2021-11-03 13:04:29.196 ERROR 17524 --- [ main] o.s.boot.SpringApplication : Application run failed
org.springframework.beans.factory.BeanDefinitionStoreException: Unexpected exception parsing XML document from class path resource [beans.xml]; nested exception is java.lang.NullPointerException: JAXP09020006: The argument 'systemId' can not be null.
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:417) ~[spring-beans-5.3.12.jar:5.3.12]
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:338) ~[spring-beans-5.3.12.jar:5.3.12]
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:310) ~[spring-beans-5.3.12.jar:5.3.12]
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:188) ~[spring-beans-5.3.12.jar:5.3.12]
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:224) ~[spring-beans-5.3.12.jar:5.3.12]
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:195) ~[spring-beans-5.3.12.jar:5.3.12]
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.lambda$loadBeanDefinitionsFromImportedResources$0(ConfigurationClassBeanDefinitionReader.java:390) ~[spring-context-5.3.12.jar:5.3.12]
at java.base/java.util.LinkedHashMap.forEach(LinkedHashMap.java:684) ~[na:na]
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitionsFromImportedResources(ConfigurationClassBeanDefinitionReader.java:354) ~[spring-context-5.3.12.jar:5.3.12]
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitionsForConfigurationClass(ConfigurationClassBeanDefinitionReader.java:156) ~[spring-context-5.3.12.jar:5.3.12]
at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitions(ConfigurationClassBeanDefinitionReader.java:129) ~[spring-context-5.3.12.jar:5.3.12]
at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:343) ~[spring-context-5.3.12.jar:5.3.12]
at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:247) ~[spring-context-5.3.12.jar:5.3.12]
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:311) ~[spring-context-5.3.12.jar:5.3.12]
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:112) ~[spring-context-5.3.12.jar:5.3.12]
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:746) ~[spring-context-5.3.12.jar:5.3.12]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:564) ~[spring-context-5.3.12.jar:5.3.12]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:754) ~[spring-boot-2.5.6.jar:2.5.6]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:434) ~[spring-boot-2.5.6.jar:2.5.6]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:338) ~[spring-boot-2.5.6.jar:2.5.6]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1343) ~[spring-boot-2.5.6.jar:2.5.6]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1332) ~[spring-boot-2.5.6.jar:2.5.6]
at com.example.demo.DemoApplication.main(DemoApplication.java:23) ~[classes/:na]
Caused by: java.lang.NullPointerException: JAXP09020006: The argument 'systemId' can not be null.
at java.xml/javax.xml.catalog.CatalogMessages.reportNPEOnNull(CatalogMessages.java:129) ~[na:na]
at java.xml/javax.xml.catalog.CatalogResolverImpl.resolveEntity(CatalogResolverImpl.java:70) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLEntityManager.resolveEntity(XMLEntityManager.java:1157) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaLoader.resolveDocument(XMLSchemaLoader.java:662) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.xs.traversers.XSDHandler.resolveSchema(XSDHandler.java:2082) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.xs.traversers.XSDHandler.constructTrees(XSDHandler.java:1031) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.xs.traversers.XSDHandler.parseSchema(XSDHandler.java:634) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaLoader.loadSchema(XMLSchemaLoader.java:617) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaValidator.findSchemaGrammar(XMLSchemaValidator.java:2710) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaValidator.handleStartElement(XMLSchemaValidator.java:2069) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaValidator.startElement(XMLSchemaValidator.java:829) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.scanStartElement(XMLNSDocumentScannerImpl.java:374) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl$NSContentDriver.scanRootElementHook(XMLNSDocumentScannerImpl.java:613) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:3060) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(XMLDocumentScannerImpl.java:836) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:605) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(XMLNSDocumentScannerImpl.java:112) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:534) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:888) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:824) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:141) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.parsers.DOMParser.parse(DOMParser.java:246) ~[na:na]
at java.xml/com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse(DocumentBuilderImpl.java:339) ~[na:na]
at org.springframework.beans.factory.xml.DefaultDocumentLoader.loadDocument(DefaultDocumentLoader.java:77) ~[spring-beans-5.3.12.jar:5.3.12]
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadDocument(XmlBeanDefinitionReader.java:432) ~[spring-beans-5.3.12.jar:5.3.12]
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:390) ~[spring-beans-5.3.12.jar:5.3.12]
... 22 common frames omitted
使用调试器，我已经确定在解析 applicationContext.xml 文件时尝试解析“http://www.w3.org/XML/1998/namespace”时出现问题，因为在 java.xml.catalog.CatalogResolverImpl 中是 resolveEntity方法检查 systemId 是否为空。
有没有办法通过 Spring 使用 Java 11+ 的 Java 内置 XML 目录功能？