Java 启用预览特性

问题

从Java 13开始支持文本块（多行字符串），可以替代从前丑陋的多行字符串拼接。即使是 Java14 该特性也是预览特性。

报错如下：Text Blocks is a preview feature and disabled by default. Use --enable-preview to enable

解决方案

eclipse

maven

修改 pom.xml 文件

<project>
	...
	<properties>
		<java.version>13java.version>
		<maven.compiler.source>13maven.compiler.source>
		<maven.compiler.target>13maven.compiler.target>
	properties>
	
	<build>
        <plugins>
            <plugin>
                <groupId>org.springframework.bootgroupId>
                <artifactId>spring-boot-maven-pluginartifactId>
                <configuration>
                    <arguments>--enable-previewarguments>
                    <jvmArguments>--enable-previewjvmArguments>
                configuration>
            plugin>
            <plugin>
                <groupId>org.apache.maven.pluginsgroupId>
                <artifactId>maven-surefire-pluginartifactId>
                <version>2.22.2version>
                <configuration>
                    <argLine>--enable-previewargLine>
                configuration>
            plugin>
            <plugin>
                <groupId>org.apache.maven.pluginsgroupId>
                <artifactId>maven-compiler-pluginartifactId>
                <version>3.8.1version>
                <configuration>
                    <compilerArgs>--enable-previewcompilerArgs>
                configuration>
            plugin>
        plugins>
    build>
	...
project>

gradle

在 build.gradle 里添加

tasks.withType(JavaCompile) {
    options.compilerArgs += "--enable-preview"
}

命令行

编译 javac --enable-preview -source 13 -encoding utf-8 test.java

执行 java --enable-preview test