运行打包的jar时，Kotlin + Maven无法找到主类

Question

我试图打包（maven包）并运行（java -jar file.jar）一个包含java和kotlin代码的项目。 我已按照教程： https ： //michaelrice.com/2016/08/hello-world-with-kotlin-and-maven/

kotlin source src/main/kotlin java source src/main/java

我试图运行的文件位于src/main/kotlin/THEFILE.kt

在成功打包尝试运行jar后我得到一个错误Error: Could not find or load main class THEFILEKt

可能是什么原因以及如何解决？

提前致谢！！！

Pom.xml包含必要的kotlin插件和依赖：

<dependency>
        <groupId>org.jetbrains.kotlin</groupId>
        <artifactId>kotlin-stdlib-jdk8</artifactId>
        <version>${kotlin.version}</version>
</dependency>


<plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
        <plugin>
            <groupId>org.jetbrains.kotlin</groupId>
            <artifactId>kotlin-maven-plugin</artifactId>
            <version>${kotlin.version}</version>
            <executions>
                <execution>
                    <id>compile</id>
                    <phase>compile</phase>
                    <goals>
                        <goal>compile</goal>
                    </goals>
                    <configuration>
                        <sourceDirs>
                            <source>src/main/java</source>
                            <source>src/main/kotlin</source>
                        </sourceDirs>
                    </configuration>
                </execution>
                <execution>
                    <id>test-compile</id>
                    <phase>test-compile</phase>
                    <goals>
                        <goal>test-compile</goal>
                    </goals>
                </execution>
            </executions>
            <configuration>
                <jvmTarget>1.8</jvmTarget>
            </configuration>
        </plugin>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <executions>

                <execution>
                    <id>default-compile</id>
                    <phase>none</phase>
                </execution>

                <execution>
                    <id>default-testCompile</id>
                    <phase>none</phase>
                </execution>
                <execution>
                    <id>java-compile</id>
                    <phase>compile</phase>
                    <goals>
                        <goal>compile</goal>
                    </goals>
                </execution>
                <execution>
                    <id>java-test-compile</id>
                    <phase>test-compile</phase>
                    <goals>
                        <goal>testCompile</goal>
                    </goals>
                </execution>
                <execution>
                    <id>compile</id>
                    <phase>compile</phase>
                    <goals>
                        <goal>compile</goal>
                    </goals>
                </execution>
                <execution>
                    <id>testCompile</id>
                    <phase>test-compile</phase>
                    <goals>
                        <goal>testCompile</goal>
                    </goals>
                </execution>


            </executions>
        </plugin>

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-jar-plugin</artifactId>
            <version>2.6</version>
            <configuration>
                <archive>
                    <manifest>
                        <addClasspath>true</addClasspath>
                        <mainClass>
                            THEFILEKt

                        </mainClass>
                    </manifest>
                </archive>
            </configuration>
        </plugin>



        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-assembly-plugin</artifactId>
            <version>2.6</version>
            <executions>
                <execution>
                    <id>make-assembly</id>
                    <phase>package</phase>
                    <goals>
                        <goal>single</goal>
                    </goals>
                    <configuration>
                        <archive>
                            <manifest>
                                <mainClass>
                                    THEFILEKt
                                </mainClass>
                            </manifest>
                        </archive>
                        <descriptorRefs>
                            <descriptorRef>jar-with-dependencies</descriptorRef>
                        </descriptorRefs>
                    </configuration>
                </execution>
            </executions>
        </plugin>

Answer 1

当你同时拥有java和kotlin代码时会出现一些问题。 我注意到以下情况 -

• 如果我有一个名为src / main / java的文件夹，那么主类需要用Java编写。

• 如果我有一个名为src / main / kotlin的文件夹，那么主类需要用kotlin编写。

我没有尝试使用java和kotlin源文件夹。

我建议你将所有的java代码移动到kotlin文件夹。 它仍然有效。 也许当有一个java文件夹时，它希望主类在java中？ 不确定。

Answer 2

在删除maven-compiler-plugin之前我遇到了同样的问题。 pom.xml构建块：

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-surefire-plugin</artifactId>
            <configuration>
                <useSystemClassLoader>false</useSystemClassLoader>
            </configuration>
        </plugin>

        <!-- lombok -->
        <plugin>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok-maven-plugin</artifactId>
            <version>1.16.8.0</version>
            <executions>
                <execution>
                    <phase>generate-sources</phase>
                    <goals>
                        <goal>delombok</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>

        <!-- instead of default compiler -->
        <plugin>
            <groupId>org.jetbrains.kotlin</groupId>
            <artifactId>kotlin-maven-plugin</artifactId>
            <version>${kotlin.version}</version>
            <executions>
                <execution>
                    <id>compile</id>
                    <phase>process-sources</phase>
                    <goals>
                        <goal>compile</goal>
                    </goals>
                    <configuration>
                        <sourceDirs>
                            <source>src/main/java</source>
                            <source>src/main/kotlin</source>
                            <source>target/generated-sources/annotations</source>
                        </sourceDirs>
                    </configuration>
                </execution>
                <execution>
                    <id>test-compile</id>
                    <phase>test-compile</phase>
                    <goals>
                        <goal>test-compile</goal>
                    </goals>
                    <configuration>
                        <sourceDirs>
                            <source>src/test/java</source>
                            <source>src/test/kotlin</source>
                        </sourceDirs>
                    </configuration>
                </execution>
            </executions>
            <configuration>
                <jvmTarget>1.8</jvmTarget>
            </configuration>
        </plugin>
    </plugins>
</build>