runtimes.md

Runtime Selection

Scriptify defines runtime-independent contracts in api. JavaScript execution is provided by runtime modules.

GraalVM Runtime

Class:

org.densy.scriptify.js.graalvm.script.JsScript

Return type:

Script<Value>

GraalVM uses org.graalvm.polyglot.Context and evaluates JavaScript as modules.

Supported behavior:

• ES module source evaluation;
• imports through a virtual module file system;
• internal and external Scriptify modules;
• Java functions through ProxyExecutable;
• Java values/classes through GraalVM host interop;
• ScriptAccess.ALL;
• ScriptAccess.EXPLICIT through GraalVM HostAccess.EXPLICIT;
• class lookup restrictions through allowHostClassLookup;
• path restrictions for external file modules through Scriptify path access.

Use GraalVM when you need modern JavaScript module behavior and stronger engine-level host access controls.

Rhino Runtime

Class:

org.densy.scriptify.js.rhino.script.JsScript

Return type:

Script<Object>

Rhino uses org.mozilla.javascript.Context in ES6 mode.

Supported behavior:

• one-shot and compiled JavaScript evaluation;
• internal Scriptify modules;
• external Scriptify modules through source transformation;
• supported top-level import/export forms;
• Java functions through Rhino Function;
• ScriptAccess.ALL;
• ScriptAccess.EXPLICIT through restricted Java object/class wrappers;
• class lookup restrictions through Rhino ClassShutter.

Rhino is useful when you want a lighter runtime dependency. Its module support is Scriptify-provided, not a full ECMAScript module implementation.

Runtime Differences

Feature	GraalVM	Rhino
Evaluation result	org.graalvm.polyglot.Value	Java/Rhino object
Module execution	Native ESM-style source	Source transformation
Java function bridge	ProxyExecutable	Rhino Function
ScriptAccess.EXPLICIT	GraalVM host access	Restricted wrappers
External file modules	Virtual file system	Loaded and transformed by Scriptify
Best fit	Modern JS/module use	Lightweight embedding

Import Recommendation

Use the same Scriptify module API with both runtimes:

script.getModuleManager().addModule(module);

Then import from JavaScript:

import * as app from "app";