【错误】Caused by: org.xml.sax.SAXParseException: cvc-elt.1: Cannot find the declara

TOMCAT启动报错：

org.springframework.beans.factory.xml.XmlBeanDefinitionStoreException: Line 10 in XML document from class path resource [conf/Task-Context.xml] is invalid; nested exception is org.xml.sax.SAXParseException: cvc-elt.1: Cannot find the declaration of element 'beans'.
Caused by: org.xml.sax.SAXParseException: cvc-elt.1: Cannot find the declaration of element 'beans'.
	at org.apache.xerces.util.ErrorHandlerWrapper.createSAXParseException(Unknown Source)
	at org.apache.xerces.util.ErrorHandlerWrapper.error(Unknown Source)
	at org.apache.xerces.impl.XMLErrorReporter.reportError(Unknown Source)
	at org.apache.xerces.impl.XMLErrorReporter.reportError(Unknown Source)
	at org.apache.xerces.impl.xs.XMLSchemaValidator.handleStartElement(Unknown Source)
	at org.apache.xerces.impl.xs.XMLSchemaValidator.startElement(Unknown Source)
	at org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanStartElement(Unknown Source)
	at org.apache.xerces.impl.XMLNSDocumentScannerImpl$NSContentDispatcher.scanRootElementHook(Unknown Source)
	at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Unknown Source)
	at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)

问题描述：发现断网的时候就报错，一旦联上网络就OK了，说明SPRING的XML头配置依赖网站，可以改用DTD。

先看原先的XML配置：

<?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:aop="http://www.springframework.org/schema/aop"
	xmlns:tx="http://www.springframework.org/schema/tx"
	 xmlns:task="http://www.springframework.org/schema/task"
	xsi:schemaLocation="
	http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
	http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
	http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd
	 http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task.xsd">

修改如下：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN"
"http://www.springframework.org/dtd/spring-beans.dtd">
<beans>

注：我的项目版本可能比较老，要是比较新的SPRING,DTD链接应该不太一样。