Java 导入apache poi时getResourceAsStream返回null?
我通过使用maven汇编插件添加Java 导入apache poi时getResourceAsStream返回null?,java,apache-poi,maven-assembly-plugin,Java,Apache Poi,Maven Assembly Plugin,我通过使用maven汇编插件添加,从jar中读取属性文件。起初它是有效的。但是当我添加maven依赖ApachePOI时,结果变成null。类路径似乎无效 Java主类 import java.io.IOException; import java.io.InputStream; import java.util.Properties; public class Main { public static void main(String[] args) throws IOExcepti
,从jar中读取属性文件。起初它是有效的。但是当我添加maven依赖ApachePOI时,结果变成null
。类路径似乎无效
Java主类
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
public class Main {
public static void main(String[] args) throws IOException {
Properties properties = new Properties();
InputStream in = Main.class.getClassLoader().getResourceAsStream("config/application.properties");
properties.load(in);
System.out.println(properties.getProperty("application.ip"));
}
}
和pom.xml
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
<plugin>
<artifactId> maven-assembly-plugin </artifactId>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
<archive>
<manifest>
<mainClass>Main</mainClass>
</manifest>
<manifestEntries>
<Class-Path>.</Class-Path>
</manifestEntries>
</archive>
</configuration>
<executions>
<execution>
<id>make-assembly</id>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
<dependencies>
<!-- if add this dependency,I will get null in Main when getResourceAsStream("config/application.properties")-->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>4.1.0</version>
</dependency>
</dependencies>
而application.properties
application.ip=127.0.0.1
application.port=80
没有poi依赖,我得到了以下结果:
$ java -jar poi-demo-1.0-SNAPSHOT-jar-with-dependencies.jar
127.0.0.1
添加poi依赖项时,我得到空值:
$ java -jar poi-demo-1.0-SNAPSHOT-jar-with-dependencies.jar
Exception in thread "main" java.lang.NullPointerException
at java.util.Properties$LineReader.readLine(Unknown Source)
at java.util.Properties.load0(Unknown Source)
at java.util.Properties.load(Unknown Source)
at Main.main(Main.java:16)
资源必须是您的WAR或JAR文件之一。@user207421我不这么认为。例如,springboot将使用当前目录中application.properties的配置,而不是jar中的application.properties。资源必须是WAR或jar文件之一。@user207421我不这么认为。例如,springboot将使用当前目录中application.properties的配置,而不是jar中的application.properties。
$ java -jar poi-demo-1.0-SNAPSHOT-jar-with-dependencies.jar
Exception in thread "main" java.lang.NullPointerException
at java.util.Properties$LineReader.readLine(Unknown Source)
at java.util.Properties.load0(Unknown Source)
at java.util.Properties.load(Unknown Source)
at Main.main(Main.java:16)