2017-08-10 23:46:34 +00:00
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# Other JS Engines and Deployments
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There are many JS engines and deployments outside of web browsers. NodeJS is the
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most popular deployment, but there are many others for special use cases. Some
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optimize for low overhead and others optimize for ease of embedding within other
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applications. Since it was designed for ES3 engines, the library can be used in
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those settings! This demo tries to demonstrate a few alternative deployments.
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2017-09-05 05:26:50 +00:00
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Some engines provide no default global object. To create a global reference:
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```js
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var global = (function(){ return this; }).call(null);
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```
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## Swift + JavaScriptCore
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iOS and OSX ship with the JavaScriptCore framework, enabling easy JS access from
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Swift and Objective-C. Hybrid function invocation is tricky, but explicit data
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passing is straightforward.
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Binary strings can be passed back and forth using `String.Encoding.ascii`.
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2017-08-10 23:46:34 +00:00
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## Nashorn
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Nashorn ships with Java 8. It includes a command-line tool `jjs` for running JS
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scripts. It is somewhat limited but does offer access to the full Java runtime.
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`jjs` does not provide a CommonJS `require` implementation. This demo uses a
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[`shim`](https://rawgit.com/nodyn/jvm-npm/master/src/main/javascript/jvm-npm.js)
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and manually requires the library.
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The Java `nio` API provides the `Files.readAllBytes` method to read a file into
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a byte array. To use in `XLSX.read`, the demo copies the bytes into a plain JS
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array and calls `XLSX.read` with type `"array"`.
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2017-09-05 05:26:50 +00:00
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## Rhino
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[Rhino](http://www.mozilla.org/rhino) is an ES3+ engine written in Java. The
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`SheetJSRhino` class and `com.sheetjs` package show a complete JAR deployment,
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including the full XLSX source.
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Due to code generation errors, optimization must be disabled:
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```java
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Context context = Context.enter();
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context.setOptimizationLevel(-1);
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```
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2017-08-10 23:46:34 +00:00
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## duktape and skookum
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[Duktape](http://duktape.org/) is an embeddable JS engine written in C. The
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amalgamation makes integration extremely simple! Duktape understands the source
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code and can process binary strings out the box, but does not provide I/O or
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other standard library features.
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To demonstrate compatibility with duktape, this demo uses the JS runtime from
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[Skookum JS](https://github.com/saghul/sjs). Built upon the duktape engine, it
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adds a simple I/O interface to enable reading from files.
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