我试图以最基本的方式弄清楚如何使用 TeaVM 从 .java 文件编译 wasm 文件。如果我使用 TeaVM 入门页面上提供的 maven .pom 文件，我的 .java 代码相当简单并且可以成功编译为 Javascript：
package org.teavm;
public class Scorer {
public static void main(String[] args) {
Double score = testScore();
//log(score);
}
//@JSBody(params = { "value" }, script = "console.log('Value is: ' + value)")
//public static native void log(double value);
public static double testScore(){
Double score = 8.0085;
return score;
}
}
当我想做同样的事情，但将其编译为 .wasm 而不是 .js 时，我的问题就出现了。（这就是为什么从 .java 代码中注释掉 JSO 内容的原因）。我的 .pom 文件如下：
<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>org.teavm</groupId>
<artifactId>teavm-maven-webapp</artifactId>
<version>0.6.1 </version>
<packaging>war</packaging>
<properties>
<java.version>1.8</java.version>
<teavm.version>0.6.1</teavm.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<!-- Emulator of Java class library for TeaVM -->
<dependency>
<groupId>org.teavm</groupId>
<artifactId>teavm-classlib</artifactId>
<version>${teavm.version}</version>
<scope>provided</scope>
</dependency>
<!-- JavaScriptObjects (JSO) - a JavaScript binding for TeaVM -->
<dependency>
<groupId>org.teavm</groupId>
<artifactId>teavm-jso-apis</artifactId>
<version>${teavm.version}</version>
<scope>provided</scope>
</dependency>
<!-- Servlet 3.1 specification -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
<scope>provided</scope>
</dependency>
</dependencies>
<build>
<plugins>
<!-- Configure Java compiler to use Java 8 syntax -->
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>${java.version}</source>
<target>${java.version}</target>
</configuration>
</plugin>
<!-- Configure WAR plugin to include JavaScript !AND WASM! files generated by TeaVM -->
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>2.4</version>
<configuration>
<webResources>
<resource>
<directory>${project.build.directory}/generated/js</directory>
</resource>
<resource>
<directory>${project.build.directory}/generated/wasm</directory>
</resource>
</webResources>
</configuration>
</plugin>
<!-- Configure TeaVM -->
<plugin>
<groupId>org.teavm</groupId>
<artifactId>teavm-maven-plugin</artifactId>
<version>${teavm.version}</version>
<executions>
<execution>
<id>web-client</id>
<goals>
<goal>compile</goal>
</goals>
<configuration>
<!-- Directory where TeaVM should put generated files. This configuration conforms to the settings
of the WAR plugin -->
<targetDirectory>${project.build.directory}/generated/js/teavm</targetDirectory>
<!-- Main class, containing static void main(String[]) -->
<mainClass>org.teavm.Scorer</mainClass>
<!-- Whether TeaVM should produce minified JavaScript. Can reduce JavaScript file size more than
two times -->
<minifying>false</minifying>
<!-- Whether TeaVM should produce debug information for its built-in debugger -->
<debugInformationGenerated>true</debugInformationGenerated>
<!-- Whether TeaVM should produce source maps file -->
<sourceMapsGenerated>true</sourceMapsGenerated>
<!-- Whether TeaVM should also put source files into output directory,
for compatibility with source maps -->
<sourceFilesCopied>true</sourceFilesCopied>
<!-- Optimization level. Valid values are: SIMPLE, ADVANCED, FULL -->
<optimizationLevel>FULL</optimizationLevel>
<!-- <targetType>WEBASSEMBLY</targetType> -->
</configuration>
</execution>
<execution>
<id>wasm-client</id>
<goals>
<goal>compile</goal>
</goals>
<configuration>
<!-- Directory where TeaVM should put generated files. This configuration conforms to the settings
of the WAR plugin -->
<targetDirectory>${project.build.directory}/generated/wasm/teavm-wasm</targetDirectory>
<!-- Main class, containing static void main(String[]) -->
<mainClass>org.teavm.Scorer</mainClass>
<!-- Whether TeaVM should produce debug information for its built-in debugger -->
<debugInformationGenerated>true</debugInformationGenerated>
<targetType>WEBASSEMBLY</targetType>
<!-- Optimization level. Valid values are: SIMPLE, ADVANCED, FULL -->
<optimizationLevel>FULL</optimizationLevel>
<minHeapSize>1</minHeapSize>
<maxHeapSize>16</maxHeapSize>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
这基本上是“入门”.pom 文件和来自位于此处的基准示例的 .pom 文件的组合：https ://github.com/konsoletyper/teavm/blob/master/samples/benchmark/pom.xml
我将第二个执行块添加到teavm 插件配置部分。基准 .pom 中的所有其他内容看起来都与 .wasm 文件生成无关。
当我尝试构建时（使用mvn clean package，与我用于仅 js 版本的相同），我收到以下错误：
[INFO] Running TeaVM
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 4.876 s
[INFO] Finished at: 2022-02-24T18:43:21-05:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.teavm:teavm-maven-plugin:0.6.1:compile (wasm-client) on project teavm-maven-webapp: Unexpected error occurred: Array index out of range: 0 -> [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/MojoExecutionException
有谁知道这可能是什么原因造成的？我检查了错误日志中的 apache wiki 页面 url，它并没有真正帮助。我以前从未使用过 TeaVM 或 Maven，这让我有点难过。