Java不允许我使用记录

Question

我正在运行JDK 15(刚刚下载(，当我尝试使用记录时遇到编译错误：

public class Runner {
// This gives a compile error
record Point(int x, int y) {}
}

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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>something</groupId>
<artifactId>other-thing</artifactId>
<version>1.0.0-SNAPSHOT</version>
<properties>
<java.version>15</java.version>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<source>${java.version}</source>
<target>${java.version}</target>
</configuration>
</plugin>
</plugins>
</build>
</project>

Answer 1

Records仍然是Java 15中的预览功能，因此在运行编译器时需要添加--enable-preview参数：

<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<source>${java.version}</source>
<target>${java.version}</target>
<compilerArgs>
<arg>--enable-preview</arg>
</compilerArgs>
</configuration>
</plugin>