java - 在 Eclipse Maven 项目中更改动态 Web 模块版本

Question

我正在尝试设置 Dynamic Web Module 3.0 以支持 Java 6 开发。每当我执行 Maven > Update Project 时，我都会在 eclipse 的“问题”选项卡中收到此错误。

Dynamic Web Module 3.1 需要 Java 1.7 或更新版本。

它看起来好像没有任何问题，但我一定是遗漏了什么，因为我一直收到这个错误。

下面是我的.settings/org.eclipse.wst.common.project.facet.core.xml的内容

<?xml version="1.0" encoding="UTF-8"?>
<faceted-project>
  <fixed facet="jst.java"/>
  <fixed facet="jst.web"/>
  <installed facet="jst.java" version="1.6"/>
  <installed facet="jst.web" version="3.0"/>
</faceted-project>

在 eclipse 中，我的 Java 编译器正确设置为 1.6。在 Project Facets 选项卡中，Dynamic Web Module 被正确指定为版本 3.0，并且 Java 在 Project Facets 下也显示为 1.6。

在我的 pom.xml 文件中，我还相应地设置了 Java 版本:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.1</version>
    <configuration>
        <source>1.6</source>
        <target>1.6</target>
    </configuration>
</plugin>

作为旁注，我还应该提到我正在使用 WebApplicationInitializer 进行纯 Java 构建并且没有 web.xml 文件。

非常感谢任何帮助，因为我试图消除这个看似无关的错误消息。

编辑:添加了 pom.xml 内容

<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/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>net.XXXXX</groupId>
    <artifactId>XXXXX</artifactId>
    <version>1.0-SNAPSHOT</version>

    <name>XXXXX</name>
    <packaging>war</packaging>
    <url>http://maven.apache.org</url>

    <build>
        <finalName>XXXXX</finalName>

        <plugins>

            <!-- Source level should be 1.6 (not Maven default) for Java EE 6 projects -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.6</source>
                    <target>1.6</target>
                </configuration>
            </plugin>

            <!-- When using xml-less approach, need to disable Maven's warning about 
                missing web.xml -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <configuration>
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                </configuration>
            </plugin>

        </plugins>
    </build>
    <dependencies>

        <!-- JUnit testing -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
            <scope>test</scope>
        </dependency>

        <!-- Spring Core -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>4.0.2.RELEASE</version>
        </dependency>

        <!-- Spring MVC -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.0.2.RELEASE</version>
        </dependency>

        <!-- Spring Context without commons-logging -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.0.2.RELEASE</version>
            <exclusions>
                <exclusion>
                    <groupId>commons-logging</groupId>
                    <artifactId>commons-logging</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <!-- Spring Security core -->
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-core</artifactId>
            <version>3.2.1.RELEASE</version>
        </dependency>

        <!-- Spring Security config -->
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-config</artifactId>
            <version>3.2.1.RELEASE</version>
        </dependency>

        <!-- Spring Security web -->
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-web</artifactId>
            <version>3.2.1.RELEASE</version>
        </dependency>

        <!-- jcl-over-slf4j -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>jcl-over-slf4j</artifactId>
            <version>1.7.6</version>
        </dependency>

        <!-- slf4j-api -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.6</version>
        </dependency>

        <!-- slf4j-log4j12 -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>1.7.6</version>
        </dependency>

        <!-- log4j -->
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>

        <!-- Need servlet API for compiling the classes. Not needed in runtime -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.1.0</version>
            <scope>provided</scope>
        </dependency>

        <!-- Required for xml-less configuration of Spring via @Configuration annotations -->
        <dependency>
            <groupId>cglib</groupId>
            <artifactId>cglib-nodep</artifactId>
            <version>3.1</version>
        </dependency>

        <!-- Required for getting Spring working with Hibernate -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-orm</artifactId>
            <version>4.0.2.RELEASE</version>
        </dependency>

        <!-- Hibernate -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>4.3.4.Final</version>
        </dependency>

        <!-- For using JPA instead of "pure Hibernate" -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>4.3.4.Final</version>
        </dependency>

        <!-- DB connection pooling for production applications -->
        <dependency>
            <groupId>commons-dbcp</groupId>
            <artifactId>commons-dbcp</artifactId>
            <version>20030825.184428</version>
        </dependency>

        <!-- Concrete JDBC driver for MySQL DB -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.29</version>
        </dependency>

        <!-- Add Taglib support -->
        <dependency>
            <groupId>jstl</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>

    </dependencies>

</project>

Answer 1

在我们的项目中，我们添加更改 web.xml 根元素的声明，更改自:

<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd">

到:

<web-app xmlns="http://java.sun.com/xml/ns/javaee" 
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
         version="2.5" >

可能 Eclipse 期望它满足不同的 Servlet 版本规范。在我们的案例中，我们既没有编译问题也没有运行时问题。

编辑:在您的情况下，如果您没有使用 web.xml 文件，则存在以下 pom 的依赖项，这可能会混淆 Eclipse 的 maven 插件:

<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>javax.servlet-api</artifactId>
    <version>3.1.0</version>
    <scope>provided</scope>
</dependency>

将其更改为“3.0.1”。 (事实证明 WebApplicationInitializer 需要“Servlet 3.0+ 环境”而不是 3.1+)