尝试使用IntelliJ 12.1.4和Java 7创建一个使用Maven 3.0.5的jar时出错。我能够通过IDE运行项目没有任何问题,但是当我尝试打包它时,我得到了以下错误。
我的POM的相关部分(摘自Maven By Example
Sonatype
):
<build>
<plugins>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<descriptorRefs>jar-with-dependencies</descriptorRefs>
</configuration>
</plugin>
</plugins>
</build>
,错误是:
[ERROR] ...[33,55] error: diamond operator is not supported in -source 1.5
[ERROR] ...[207,7] error: try-with-resources is not supported in -source 1.5
[ERROR] ...[73,52] error: diamond operator is not supported in -source 1.5
[ERROR] ...[129,40] error: multi-catch statement is not supported in -source 1.5
[ERROR] ...[44,6] error: try-with-resources is not supported in -source 1.5
[ERROR] ...[28,39] error: diamond operator is not supported in -source 1.5
[ERROR] ...[31,7] error: try-with-resources is not supported in -source 1.5
[ERROR] ...[38,6] error: try-with-resources is not supported in -source 1.5
[ERROR] ...[34,41] error: diamond operator is not supported in -source 1.5
[ERROR] ...[77,43] error: diamond operator is not supported in -source 1.5
[ERROR] ...[84,6] error: try-with-resources is not supported in -source 1.5
[ERROR] ...[281,38] error: diamond operator is not supported in -source 1.5
[ERROR] ...[13,55] error: diamond operator is not supported in -source 1.5
[ERROR] ...[155,7] error: try-with-resources is not supported in -source 1.5
如何让maven使用source 1.7?
答案 0 :(得分:43)
要回答第一部分,请将以下行添加到POM以设置语言级别
<properties>
<maven.compiler.source>1.7</maven.compiler.source>
<maven.compiler.target>1.7</maven.compiler.target>
</properties>
添加这些行后,您可以成功构建jar,但是当您运行它时,您的jar会出现no main manifest attribute
错误。
这可以通过像java -cp app.jar com.somepackage.SomeClass
或者纠正这个并制作一个可执行的jar,让你的pom看起来像
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>copy-dependencies</id>
<phase>prepare-package</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<outputDirectory>${project.build.directory}/lib</outputDirectory>
<overWriteReleases>false</overWriteReleases>
<overWriteSnapshots>false</overWriteSnapshots>
<overWriteIfNewer>true</overWriteIfNewer>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<classpathPrefix>lib/</classpathPrefix>
<mainClass>fully.qualified.main</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>
这个pom通过将依赖项复制到构建目录,然后使用包含的库创建jar来克服jar-with-dependencies
descriptorRef的一些问题。
感谢@André Aronsen了解他的pom解决方案。
关于没有主要的清单错误,有很多关于这个问题的帖子,有些解决方案有效,有些则没有。这个解决方案对我有用,所以我已将它包含在这篇文章中以供完成。
使用Java 7,Maven 3.0.5和JetBrains IntelliJ IDEA 12.1.4 Ultimate测试。