java 为什么maven编译失败？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/39825551/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Why maven compilation failure?
提问by testuser
I am trying build a java project with maven. I check maven command through mvn -vand it gives following output
我正在尝试用 maven 构建一个 java 项目。我检查了 Maven 命令mvn -v，它提供了以下输出
Apache Maven 3.3.9 (bb52d8502b132ec0a5a3f4c09453c07478323dc5; 2015-11-10T18:41:47+02:00)
Maven home: C:\Program Files\Apache\Maven\apache-maven-3.3.9\bin\..
Java version: 1.8.0_101, vendor: Oracle Corporation
Java home: C:\Program Files\Java\jdk1.8.0_101\jre
Default locale: en_US, platform encoding: Cp1252
OS name: "windows 10", version: "10.0", arch: "amd64", family: "dos"
I add org.joda.time.LocalTimeto HelloWorld.javaas follows
我添加org.joda.time.LocalTime到HelloWorld.java如下
package hello;
import org.joda.time.LocalTime;
public class HelloWorld {
public static void main(String[] args) {
LocalTime currentTime = new LocalTime();
System.out.println("The current local time is: " + currentTime);
Greeter greeter = new Greeter();
System.out.println(greeter.sayHello());
}
}
Therefore I add joda-timedependency to my pom.xml. Here is my pom.xml
因此，我joda-time向我的pom.xml. 这是我的pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<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>org.springframework</groupId>
<artifactId>gs-maven</artifactId>
<packaging>jar</packaging>
<version>0.1.0</version>
<dependencies>
<!-- tag::joda[] -->
<dependency>
<groupId>joda-time</groupId>
<artifactId>joda-time</artifactId>
<version>2.2</version>
</dependency>
<!-- end::joda[] -->
<!-- tag::junit[] -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<!-- end::junit[] -->
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>2.1</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<transformers>
<transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
<mainClass>hello.HelloWorld</mainClass>
</transformer>
</transformers>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
Whenever I am going to run the mvn compileit gives the output as
每当我要运行mvn compile它时，它都会给出输出
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building gs-maven 0.1.0
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ gs-maven ---
[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory H:\Projects\JAVA\web\unzipped\gs-maven\initial\src\main\resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ gs-maven ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding Cp1252, i.e. build is platform dependent!
[INFO] Compiling 2 source files to H:\Projects\JAVA\web\unzipped\gs-maven\initial\target\classes
[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR :
[INFO] -------------------------------------------------------------
[ERROR] /H:/Projects/JAVA/web/unzipped/gs-maven/initial/src/main/java/hello/HelloWorld.java:[3,21] package org.joda.time does not exist
[ERROR] /H:/Projects/JAVA/web/unzipped/gs-maven/initial/src/main/java/hello/HelloWorld.java:[7,9] cannot find symbol
symbol: class LocalTime
location: class hello.HelloWorld
[ERROR] /H:/Projects/JAVA/web/unzipped/gs-maven/initial/src/main/java/hello/HelloWorld.java:[7,37] cannot find symbol
symbol: class LocalTime
location: class hello.HelloWorld
[INFO] 3 errors
[INFO] -------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.647 s
[INFO] Finished at: 2016-10-03T09:11:07+03:00
[INFO] Final Memory: 14M/114M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile (default-compile) on project gs-maven: Compilation failure: Compilation failure:
[ERROR] /H:/Projects/JAVA/web/unzipped/gs-maven/initial/src/main/java/hello/HelloWorld.java:[3,21] package org.joda.time does not exist
[ERROR] /H:/Projects/JAVA/web/unzipped/gs-maven/initial/src/main/java/hello/HelloWorld.java:[7,9] cannot find symbol
[ERROR] symbol: class LocalTime
[ERROR] location: class hello.HelloWorld
[ERROR] /H:/Projects/JAVA/web/unzipped/gs-maven/initial/src/main/java/hello/HelloWorld.java:[7,37] cannot find symbol
[ERROR] symbol: class LocalTime
[ERROR] location: class hello.HelloWorld
[ERROR] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException
Please let me inform what I am doing wrong.
请让我告知我做错了什么。
N.B: I am just following Building Java Projects with Maventutorial as a beginner.
注意：作为初学者，我只是按照使用 Maven教程构建 Java 项目。
回答by Keshan Nageswaran
Your Maven is reading Java version as 1.8.0_101, Where as the pom.xml is not updated
您的 Maven 将 Java 版本读取为 1.8.0_101，其中 pom.xml 未更新
1) Try installing the required verison. Have the JAVA_HOMEand pom.xmlupdated to the same jdk installation path
1) 尝试安装所需的版本。将JAVA_HOME和pom.xml更新为相同的 jdk 安装路径
2) mvn clean install- What this does is clear any compiled files you have, making sure that you're really compiling each module from scratch.
2) mvn clean install- 这样做是清除您拥有的所有编译文件，确保您真正从头开始编译每个模块。
