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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* published by the Free Software Foundation. Oracle designates this
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*
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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/**
* Provides the implementation of Nashorn script engine and
* the runtime environment for programs written in ECMAScript 5.1.
* <p>
* Nashorn is a runtime environment for programs written in ECMAScript 5.1.
* </p>
*
* <h1>Usage</h1>
*
* The recommended way to use Nashorn is through the
* <a href="http://jcp.org/en/jsr/detail?id=223" target="_top">JSR-223
* "Scripting for the Java Platform"</a> APIs found in the
* {@link javax.script} package. Usually, you'll obtain a
* {@link javax.script.ScriptEngine} instance for Nashorn using:
* <pre>
import javax.script.*;
...
ScriptEngine nashornEngine = new ScriptEngineManager().getEngineByName("nashorn");
</pre>
*
* and then use it just as you would any other JSR-223 script engine. See
* {@link jdk.nashorn.api.scripting} package for details.
* <h1>Compatibility</h1>
* Nashorn is 100% compliant with the
* <a href="http://www.ecma-international.org/publications/standards/Ecma-262.htm"
* target="_top">ECMA-262 Standard, Edition 5.1</a>.
* It requires a Java Virtual Machine that implements the
* <a href="http://jcp.org/en/jsr/detail?id=292" target="_top">
* JSR-292 "Supporting Dynamically Typed Languages on the Java Platform"</a>
* specification (often referred to as "invokedynamic"), as well as
* the already mentioned JSR-223.
*
* <h1>Interoperability with the Java platform</h1>
*
* In addition to being a 100% ECMAScript 5.1 runtime, Nashorn provides features
* for interoperability of the ECMAScript programs with the Java platform.
* In general, any Java object put into the script engine's context will be
* visible from the script. In terms of the standard, such Java objects are not
* considered "native objects", but rather "host objects", as defined in
* section 4.3.8. This distinction allows certain semantical differences
* in handling them compared to native objects. For most purposes, Java objects
* behave just as native objects do: you can invoke their methods, get and set
* their properties. In most cases, though, you can't add arbitrary properties
* to them, nor can you remove existing properties.
*
* <h2>Java collection handling</h2>
*
* Native Java arrays and {@link java.util.List}s support indexed access to
* their elements through the property accessors, and {@link java.util.Map}s
* support both property and element access through both dot and square-bracket
* property accessors, with the difference being that dot operator gives
* precedence to object properties (its fields and properties defined as
* {@code getXxx} and {@code setXxx} methods) while the square bracket
* operator gives precedence to map elements. Native Java arrays expose
* the {@code length} property.
*
* <h2>ECMAScript primitive types</h2>
*
* ECMAScript primitive types for number, string, and boolean are represented
* with {@link java.lang.Number}, {@link java.lang.CharSequence}, and
* {@link java.lang.Boolean} objects. While the most often used number type
* is {@link java.lang.Double} and the most often used string type is
* {@link java.lang.String}, don't rely on it as various internal optimizations
* cause other subclasses of {@code Number} and internal implementations of
* {@code CharSequence} to be used.
*
* <h2>Type conversions</h2>
*
* When a method on a Java object is invoked, the arguments are converted to
* the formal parameter types of the Java method using all allowed ECMAScript
* conversions. This can be surprising, as in general, conversions from string
* to number will succeed according to Standard's section 9.3 "ToNumber"
* and so on; string to boolean, number to boolean, Object to number,
* Object to string all work. Note that if the Java method's declared parameter
* type is {@code java.lang.Object}, Nashorn objects are passed without any
* conversion whatsoever; specifically if the JavaScript value being passed
* is of primitive string type, you can only rely on it being a
* {@code java.lang.CharSequence}, and if the value is a number, you can only
* rely on it being a {@code java.lang.Number}. If the Java method declared
* parameter type is more specific (e.g. {@code java.lang.String} or
* {@code java.lang.Double}), then Nashorn will of course ensure
* the required type is passed.
*
* <h2>SAM types</h2>
*
* As a special extension when invoking Java methods, ECMAScript function
* objects can be passed in place of an argument whose Java type is so-called
* "single abstract method" or "SAM" type. While this name usually covers
* single-method interfaces, Nashorn is a bit more versatile, and it
* recognizes a type as a SAM type if all its abstract methods are
* overloads of the same name, and it is either an interface, or it is an
* abstract class with a no-arg constructor. The type itself must be public,
* while the constructor and the methods can be either public or protected.
* If there are multiple abstract overloads of the same name, the single
* function will serve as the shared implementation for all of them,
* <em>and additionally it will also override any non-abstract methods of
* the same name</em>. This is done to be consistent with the fact that
* ECMAScript does not have the concept of overloaded methods.
*
* <h2>The {@code Java} object</h2>
*
* Nashorn exposes a non-standard global object named {@code Java} that is
* the primary API entry point into Java platform-specific functionality.
* You can use it to create instances of Java classes, convert from Java arrays
* to native arrays and back, and so on.
*
* <h2>Other non-standard built-in objects</h2>
*
* In addition to {@code Java}, Nashorn also exposes some other
* non-standard built-in objects:
* {@code JSAdapter}, {@code JavaImporter}, {@code Packages}
*
* @provides javax.script.ScriptEngineFactory
* @moduleGraph
* @since 9
*/
module jdk.scripting.nashorn {
requires java.logging;
requires jdk.dynalink;
requires transitive java.scripting;
exports jdk.nashorn.api.scripting;
exports jdk.nashorn.api.tree;
exports jdk.nashorn.internal.runtime to
jdk.scripting.nashorn.shell;
exports jdk.nashorn.internal.objects to
jdk.scripting.nashorn.shell;
exports jdk.nashorn.tools to
jdk.scripting.nashorn.shell;
provides javax.script.ScriptEngineFactory with
jdk.nashorn.api.scripting.NashornScriptEngineFactory;
provides jdk.dynalink.linker.GuardingDynamicLinkerExporter with
jdk.nashorn.api.linker.NashornLinkerExporter;
}