无法编译 maven 项目 [英] Cannot compile maven project
本文介绍了无法编译 maven 项目的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我使用 confluent 的人工制品开始了一个简单的项目.但是当我尝试使用 mvn clean install 或 mvn clean package 编译项目时，我收到类似
I started a simple project using an artefact from confluent. But when I try to compile the project using mvn clean install or mvn clean package I am getting message like
[ERROR] C:\Users\its\git\datakmu\service-stack\stream-data-preprocessor\src\main\java\at\ac\fhsalzburg\datakmu\service\DataPreProcessor.java:[1]
package at.ac.fhsalzburg.datakmu.service;
^
The type java.lang.Object cannot be resolved. It is indirectly referenced from required .class files
[ERROR] C:\Users\its\git\datakmu\service-stack\stream-data-preprocessor\src\main\java\at\ac\fhsalzburg\datakmu\service\DataPreProcessor.java:[3]
public class DataPreProcessor {
^^^^^^^^^^^^^^^^
Implicit super constructor Object() is undefined for default constructor. Must define an explicit constructor
[ERROR] C:\Users\its\git\datakmu\service-stack\stream-data-preprocessor\src\main\java\at\ac\fhsalzburg\datakmu\service\DataPreProcessor.java:[4]
public static void main(String[] args) {
^^^^^^
String cannot be resolved to a type
表示未找到基本 SDK 类，例如无法解析类型 java.lang.Object".我正在与其他几个 Maven 项目合作，它们工作正常.我不明白，这一定是一些愚蠢的错误.
indicating that basic SDK classes are not found like "The type java.lang.Object cannot be resolved". I am working with several other Maven project and they work fine. I do not get it, it must be really some stupid error.
在这里你可以找到 pom.xml 文件:
Here you can find the pom.xml file:
<!--
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->
<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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>stream-data-preprocessor</groupId>
<artifactId>stream-data-preprocessor</artifactId>
<version>0.1</version>
<packaging>jar</packaging>
<name>Kafka Streams Quickstart :: Java</name>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<slf4j.version>1.7.7</slf4j.version>
<log4j.version>1.2.17</log4j.version>
<java.version>8</java.version>
<avro.version>1.9.1</avro.version>
<gson.version>2.2.4</gson.version>
<kafka.version>2.5.0</kafka.version>
<confluent.version>5.5.1</confluent.version>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<repositories>
<repository>
<id>apache.snapshots</id>
<name>Apache Development Snapshot Repository</name>
<url>https://repository.apache.org/content/repositories/snapshots/</url>
<releases>
<enabled>false</enabled>
</releases>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
<repository>
<id>confluent</id>
<name>Confluent</name>
<url>https://packages.confluent.io/maven/</url>
</repository>
</repositories>
<!--
Execute "mvn clean package -Pbuild-jar"
to build a jar file out of this project!
-->
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>${maven.compiler.source}</source>
<target>${maven.compiler.target}</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.avro</groupId>
<artifactId>avro-maven-plugin</artifactId>
<version>${avro.version}</version>
<executions>
<execution>
<phase>generate-sources</phase>
<goals>
<goal>schema</goal>
</goals>
<configuration>
<sourceDirectory>${project.basedir}/src/main/resources/avro/</sourceDirectory>
<includes>
<include>SensorValue.avsc</include>
</includes>
<outputDirectory>${project.build.directory}/generated-sources</outputDirectory>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>io.confluent</groupId>
<artifactId>kafka-schema-registry-maven-plugin</artifactId>
<version>${confluent.version}</version>
<configuration>
<schemaRegistryUrls>
<param>http://localhost:28081</param>
</schemaRegistryUrls>
<subjects>
<transactions-value>src/main/resources/avro/Sentence.avsc</transactions-value>
</subjects>
<outputDirectory/>
</configuration>
<goals>
<goal>test-compatibility</goal>
</goals>
</plugin>
</plugins>
<pluginManagement>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>${maven.compiler.source}</source>
<target>${maven.compiler.target}</target>
<compilerId>jdt</compilerId>
</configuration>
<dependencies>
<dependency>
<groupId>org.eclipse.tycho</groupId>
<artifactId>tycho-compiler-jdt</artifactId>
<version>0.21.0</version>
</dependency>
</dependencies>
</plugin>
<plugin>
<groupId>org.eclipse.m2e</groupId>
<artifactId>lifecycle-mapping</artifactId>
<version>1.0.0</version>
<configuration>
<lifecycleMappingMetadata>
<pluginExecutions>
<pluginExecution>
<pluginExecutionFilter>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<versionRange>[2.4,)</versionRange>
<goals>
<goal>single</goal>
</goals>
</pluginExecutionFilter>
<action>
<ignore/>
</action>
</pluginExecution>
<pluginExecution>
<pluginExecutionFilter>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<versionRange>[3.1,)</versionRange>
<goals>
<goal>testCompile</goal>
<goal>compile</goal>
</goals>
</pluginExecutionFilter>
<action>
<ignore/>
</action>
</pluginExecution>
</pluginExecutions>
</lifecycleMappingMetadata>
</configuration>
</plugin>
</plugins>
</pluginManagement>
</build>
<dependencies>
<!-- Apache Kafka dependencies -->
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-streams</artifactId>
<version>${kafka.version}</version>
</dependency>
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
<version>${kafka.version}</version>
</dependency>
<!-- Dependencies below are required/recommended only when using Apache Avro. -->
<dependency>
<groupId>io.confluent</groupId>
<artifactId>kafka-avro-serializer</artifactId>
<version>${confluent.version}</version>
</dependency>
<dependency>
<groupId>org.apache.avro</groupId>
<artifactId>avro</artifactId>
<version>${avro.version}</version>
</dependency>
</dependencies>
</project>
据我所知，maven也配置正确:
Also maven is configured correctly, as far as I can see:
Maven home: C:\Users\its\scoop\apps\maven\current
Java version: 11.0.2, vendor: Oracle Corporation, runtime: C:\Program Files\Java\jdk-11.0.2
Default locale: de_AT, platform encoding: Cp1252
OS name: "windows 10", version: "10.0", arch: "amd64", family: "windows"
为了完整起见，主要的java类.我从原型中删除了所有其他代码片段:
For completeness the main java class. I deleted all other code snippets from the archetype:
package at.ac.fhsalzburg.datakmu.service;
public class DataPreProcessor {
public static void main(String[] args) {
//TODO
}
}
有人可以帮忙吗?如果您需要任何进一步的输入，请告诉我！谢谢
Could someone help? If you need any further input just let me know! Thx
推荐答案
在您的 pom.xml 中，您有以下代码段.在 src/main/resources 中创建 avro 文件夹或删除 avro 部分.然后执行 mvn clean verify 以确保您的项目构建
In your pom.xml you have the following snippet. Either create the avro folder in src/main/resources or remove the avro part. Then do a mvn clean verify to make sure your project builds
<execution>
<phase>generate-sources</phase>
<goals>
<goal>schema</goal>
</goals>
<configuration>
<sourceDirectory>${project.basedir}/src/main/resources/avro/</sourceDirectory>
<includes>
<include>SensorValue.avsc</include>
</includes>
<outputDirectory>${project.build.directory}/generated-sources</outputDirectory>
</configuration>
</execution>
这篇关于无法编译 maven 项目的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
查看全文
