spring - java 9模块从A和B读取包X

Question

我正在尝试将 spring boot 与 java 9 和 gradle 一起使用。我无法运行我的简单代码，出现以下错误：-

Information:java: Errors occurred while compiling module 'Java9Gradle_main'
Information:javac 9-ea was used to compile java sources
Information:6/9/2017 10:40 PM - Compilation completed with 65 errors and 0 warnings in 15s 200ms
Error:java: module  reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module  reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.boot.starter.web reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.boot.starter.web reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.boot.autoconfigure reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.boot.autoconfigure reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.boot.starter.logging reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.boot.starter.logging reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.core reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.core reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module snakeyaml reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module snakeyaml reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.boot.starter.tomcat reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.boot.starter.tomcat reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module hibernate.validator reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module hibernate.validator reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module jackson.databind reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module jackson.databind reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.web reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.web reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.webmvc reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.webmvc reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.context reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.context reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module logback.classic reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module logback.classic reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module jcl.over.slf4j reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module jcl.over.slf4j reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module jul.to.slf4j reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module jul.to.slf4j reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module log4j.over.slf4j reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module log4j.over.slf4j reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module commons.logging reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module commons.logging reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module tomcat.embed.core reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module tomcat.embed.core reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module tomcat.embed.el reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module tomcat.embed.el reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module tomcat.embed.websocket reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module tomcat.embed.websocket reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module validation.api reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module validation.api reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module jboss.logging reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module jboss.logging reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module classmate reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module classmate reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module jackson.annotations reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module jackson.annotations reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module jackson.core reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module jackson.core reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.aop reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.aop reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.beans reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.beans reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.expression reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.expression reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module logback.core reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module logback.core reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module slf4j.api reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module slf4j.api reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.boot.starter reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.boot.starter reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
Error:java: module spring.boot reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging
Error:java: module spring.boot reads package org.apache.commons.logging.impl from both jcl.over.slf4j and commons.logging
D:\project\Java9Gradle\src\main\java\module-info.java
Error:(1, 1) java: module Java9Gradle.main reads package org.apache.commons.logging from both jcl.over.slf4j and commons.logging

我的依赖文件和 module-info.java 文件非常简单。

module Java9Gradle.main {
    requires spring.boot;
}


group 'Java9Gradle'
version '1.0-SNAPSHOT'

apply plugin: 'java'

sourceCompatibility = 1.9

repositories {
    mavenCentral()
}

dependencies {
    // https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter
    compile group: 'org.springframework.boot', name: 'spring-boot-starter', version: '1.5.3.RELEASE'
    // https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-web
    compile group: 'org.springframework.boot', name: 'spring-boot-starter-web', version: '1.5.3.RELEASE'
    testCompile group: 'junit', name: 'junit', version: '4.12'
}

有人可以帮忙吗？

谢谢，

阿马尔

Answer 1

排除传递依赖使其工作并调整 module-info.java ！！！

compile("org.springframework.boot:spring-boot-starter:1.5.3.RELEASE") {
        exclude group: 'commons-logging', module: 'commons-logging'
    }
    compile("org.springframework.boot:spring-boot-starter-web:1.5.3.RELEASE"){
        exclude group: 'commons-logging', module: 'commons-logging'
    }

Answer 2

根据Jigsaw 规格

互不干扰——Java 编译器、虚拟机和运行时系统必须确保包含同名包的模块不会相互干扰。如果两个不同的模块包含同名的包，那么从每个模块的角度来看，该包中的所有类型和成员都仅由该模块定义。一个模块中该包中的代码不得访问另一个模块中该包中的包私有类型或成员。

这在@Andy here的回答中被称为拆分包。因此，解决方案是解开这些包，并确保包含在您的模块中并且只能通过一个模块访问的包。jcl.over.slf4jcommons.logging

---

您可以分析这两个依赖项spring-boot-starter:1.5.3.RELEASE并spring-boot-starter-web:1.5.3.RELEASE确保两个模块中的任何一个都包含在您的项目中。

Answer 3

像 Apache Mina (sshd-core) 这样的多个库会出现此类问题，其中 sshd-core 和 sshd-common 之间存在拆分。与 Springfox Swagger 2 类似，您可以在其中遇到类似的拆分包问题：“模块 XXX 从 springfox.core 和 springfox.spi 读取包 springfox.documentation 服务。 ”

在分析了如何克服它的多种方法之后，我找到了一种适用于所有情况的解决方案。

这个想法是将有问题的库重新打包到单个 jar 中并将它们安装到您的公司（或本地存储库）中。如果您有公司范围的 nexus，则可以安装它，否则在运行整个构建之前，您可以手动将此类库安装到本地 maven 存储库。

虽然这些看起来有点矫枉过正，而且不容易做到，但实际上很容易。

您需要在主项目中创建新的 maven 模块（或者如果您没有运行多模块项目，则创建单独的 maven 项目）。然后将引入包拆分的依赖项添加到您的 pom.xml 并配置 maven 程序集插件以重新打包它们。

对于spring-fox，这将是

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-assembly-plugin</artifactId>
            <version>3.2.0</version>
            <configuration>
                <descriptorRefs>
                    <descriptorRef>jar-with-dependencies</descriptorRef>
                </descriptorRefs>
                <appendAssemblyId>false</appendAssemblyId>
            </configuration>
            <executions>
                <execution>
                    <id>make-assembly</id>
                    <phase>package</phase>
                    <goals>
                        <goal>single</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

<dependencies>
    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-swagger2</artifactId>
        <exclusions>
            <exclusion>
                <groupId>*</groupId>
                <artifactId>*</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-core</artifactId>
        <version>${io.springfox.version}</version>
        <exclusions>
            <exclusion>
                <groupId>*</groupId>
                <artifactId>*</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-swagger-ui</artifactId>
        <version>${io.springfox.version}</version>
        <exclusions>
            <exclusion>
                <groupId>*</groupId>
                <artifactId>*</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-spring-webmvc</artifactId>
        <version>${io.springfox.version}</version>
        <exclusions>
            <exclusion>
                <groupId>*</groupId>
                <artifactId>*</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-schema</artifactId>
        <version>${io.springfox.version}</version>
        <exclusions>
            <exclusion>
                <groupId>*</groupId>
                <artifactId>*</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-spring-web</artifactId>
        <version>${io.springfox.version}</version>
        <exclusions>
            <exclusion>
                <groupId>*</groupId>
                <artifactId>*</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>io.springfox</groupId>
        <artifactId>springfox-spi</artifactId>
        <exclusions>
            <exclusion>
                <groupId>*</groupId>
                <artifactId>*</artifactId>
            </exclusion>
        </exclusions>
    </dependency>

</dependencies>

请注意两点。首先<appendAssemblyId>false</appendAssemblyId>作为程序集插件的配置参数。第二次排除所有临时依赖项，使它们不包含在最终包中。

准备好 pom.xml 后，您可以转到新模块目录并运行clean install或clean package创建一个包，并将所有依赖项编译到单个 jar 中。jar 将位于您的目标文件夹下。这样，您将创建您命名的文件，例如springfox-all-3.0.0.jar（包含单个模块中的所有 springfox 代码）。

现在，您可以将此软件包安装到本地存储库中，或者更好地将其部署到您的 nexus，例如使用以下命令

mvn deploy:deploy-file -Dversion=3.0.0-SNAPSHOT -Durl=http://nexus.youc.company.net/nexus/content/repositories/yourRepoId -Dfile=springfox-all-3.0.0.jar -DgroupId=patched.io.springfox -DrepositoryId=yourRepoId -DartifactId=springfox-all

现在在您的 pom.xml 文件和 module-info.java 中使用此依赖项而不是项目中的单个依赖项集

module com.acme.your.module {

//  requires springfox.spring.web;
//  requires springfox.swagger2;
//  requires springfox.core;
//  requires springfox.spi;
  requires springfox.all;
}