java 集成graalvm js 引擎
java 内置的js 引擎nashorn已经是被淘汰的，oracle 比较推荐的是使用graalvm js，以下是一个简单的集成试用
环境准备
- 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>com.dalong.ex</groupId>
<artifactId>qlex-learnint</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<encoding>UTF-8</encoding>
<java.version>1.8</java.version>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>QLExpress</artifactId>
<version>3.2.0</version>
</dependency>
<!-- 如果使用了js-scriptengine 以下可选-->
<!-- <dependency>-->
<!-- <groupId>org.graalvm.truffle</groupId>-->
<!-- <artifactId>truffle-api</artifactId>-->
<!-- <version>20.2.0</version>-->
<!-- </dependency>-->
<!-- <dependency>-->
<!-- <groupId>org.graalvm.sdk</groupId>-->
<!-- <artifactId>graal-sdk</artifactId>-->
<!-- <version>20.2.0</version>-->
<!-- </dependency>-->
<dependency>
<groupId>org.graalvm.js</groupId>
<artifactId>js-scriptengine</artifactId>
<version>20.2.0</version>
</dependency>
<dependency>
<groupId>org.graalvm.js</groupId>
<artifactId>js</artifactId>
<version>20.2.0</version>
</dependency>
</dependencies>
<build>
<!-- Maven Shade Plugin -->
<finalName>my-expression-app</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>2.3</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<transformers>
<transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
<mainClass>Application</mainClass>
</transformer>
</transformers>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
- application.java
使用两种方法一种是polyglot 模式，一种是基于ScriptEngineManager模式的
import org.graalvm.polyglot.Context;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
/**
@author dalong
*/
public class Application {
public static void main(String[] args) throws ScriptException, NoSuchMethodException {
// qlExpression();
method1();
method2();
}
public static void method1() {
System.out.println("Hello Java!");
try (Context context = Context.newBuilder().allowAllAccess(true).build()) {
context.eval("js", "print('Hello JavaScript!');");
context.eval("js", "let user = {name:\"dalong\",age:333}; print(JSON.stringify(user))");
java.math.BigDecimal v = context.eval("js",
"var BigDecimal = Java.type('java.math.BigDecimal');" +
"BigDecimal.valueOf(10).pow(20)")
.asHostObject();
System.out.println(v.toString());
}
}
public static void method2() throws ScriptException, NoSuchMethodException {
// 注意此处可以直接使用js，因为js-scriptengine 的spi 注册的时候会自动处理了内置的nashorn
ScriptEngine eng = new ScriptEngineManager().getEngineByName("js");
eng.eval("let user = {name:\"dalong\",age:333}; print(JSON.stringify(user))");
}
}
说明
graalvm js 在性能以及js 支持上是很不错的，是很值的使用，es4x 就是基于graalvm js的，同时新版本的cratedb也是基于此的
参考资料
https://www.graalvm.org/reference-manual/js/JavaInteroperability/
https://github.com/graalvm/graaljs/blob/master/docs/user/JavaScriptCompatibility.md
