1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
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   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
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  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
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  25 
  26 /**
  27  * Provides the implementation of Nashorn script engine and
  28  * the runtime environment for programs written in ECMAScript 5.1.
  29  * <p>
  30  * Nashorn is a runtime environment for programs written in ECMAScript 5.1.
  31  * </p>
  32  *
  33  * <h1>Usage</h1>
  34  *
  35  * The recommended way to use Nashorn is through the
  36  * <a href="http://jcp.org/en/jsr/detail?id=223" target="_top">JSR-223
  37  * "Scripting for the Java Platform"</a> APIs found in the
  38  * {@link javax.script} package. Usually, you'll obtain a
  39  * {@link javax.script.ScriptEngine} instance for Nashorn using:
  40  * <pre>
  41 import javax.script.*;
  42 ...
  43 ScriptEngine nashornEngine = new ScriptEngineManager().getEngineByName("nashorn");
  44 </pre>
  45  *
  46  * and then use it just as you would any other JSR-223 script engine. See
  47  * {@link jdk.nashorn.api.scripting} package for details.
  48  * <h1>Compatibility</h1>
  49  * Nashorn is 100% compliant with the
  50  * <a href="http://www.ecma-international.org/publications/standards/Ecma-262.htm"
  51  * target="_top">ECMA-262 Standard, Edition 5.1</a>.
  52  * It requires a Java Virtual Machine that implements the
  53  * <a href="http://jcp.org/en/jsr/detail?id=292" target="_top">
  54  * JSR-292 "Supporting Dynamically Typed Languages on the Java Platform"</a>
  55  * specification (often referred to as "invokedynamic"), as well as
  56  * the already mentioned JSR-223.
  57  *
  58  * <h1>Interoperability with the Java platform</h1>
  59  *
  60  * In addition to being a 100% ECMAScript 5.1 runtime, Nashorn provides features
  61  * for interoperability of the ECMAScript programs with the Java platform.
  62  * In general, any Java object put into the script engine's context will be
  63  * visible from the script. In terms of the standard, such Java objects are not
  64  * considered "native objects", but rather "host objects", as defined in
  65  * section 4.3.8. This distinction allows certain semantical differences
  66  * in handling them compared to native objects. For most purposes, Java objects
  67  * behave just as native objects do: you can invoke their methods, get and set
  68  * their properties. In most cases, though, you can't add arbitrary properties
  69  * to them, nor can you remove existing properties.
  70  *
  71  * <h2>Java collection handling</h2>
  72  *
  73  * Native Java arrays and {@link java.util.List}s support indexed access to
  74  * their elements through the property accessors, and {@link java.util.Map}s
  75  * support both property and element access through both dot and square-bracket
  76  * property accessors, with the difference being that dot operator gives
  77  * precedence to object properties (its fields and properties defined as
  78  * {@code getXxx} and {@code setXxx} methods) while the square bracket
  79  * operator gives precedence to map elements. Native Java arrays expose
  80  * the {@code length} property.
  81  *
  82  * <h2>ECMAScript primitive types</h2>
  83  *
  84  * ECMAScript primitive types for number, string, and boolean are represented
  85  * with {@link java.lang.Number}, {@link java.lang.CharSequence}, and
  86  * {@link java.lang.Boolean} objects. While the most often used number type
  87  * is {@link java.lang.Double} and the most often used string type is
  88  * {@link java.lang.String}, don't rely on it as various internal optimizations
  89  * cause other subclasses of {@code Number} and internal implementations of
  90  * {@code CharSequence} to be used.
  91  *
  92  * <h2>Type conversions</h2>
  93  *
  94  * When a method on a Java object is invoked, the arguments are converted to
  95  * the formal parameter types of the Java method using all allowed ECMAScript
  96  * conversions. This can be surprising, as in general, conversions from string
  97  * to number will succeed according to Standard's section 9.3 "ToNumber"
  98  * and so on; string to boolean, number to boolean, Object to number,
  99  * Object to string all work. Note that if the Java method's declared parameter
 100  * type is {@code java.lang.Object}, Nashorn objects are passed without any
 101  * conversion whatsoever; specifically if the JavaScript value being passed
 102  * is of primitive string type, you can only rely on it being a
 103  * {@code java.lang.CharSequence}, and if the value is a number, you can only
 104  * rely on it being a {@code java.lang.Number}. If the Java method declared
 105  * parameter type is more specific (e.g. {@code java.lang.String} or
 106  * {@code java.lang.Double}), then Nashorn will of course ensure
 107  * the required type is passed.
 108  *
 109  * <h2>SAM types</h2>
 110  *
 111  * As a special extension when invoking Java methods, ECMAScript function
 112  * objects can be passed in place of an argument whose Java type is so-called
 113  * "single abstract method" or "SAM" type. While this name usually covers
 114  * single-method interfaces, Nashorn is a bit more versatile, and it
 115  * recognizes a type as a SAM type if all its abstract methods are
 116  * overloads of the same name, and it is either an interface, or it is an
 117  * abstract class with a no-arg constructor. The type itself must be public,
 118  * while the constructor and the methods can be either public or protected.
 119  * If there are multiple abstract overloads of the same name, the single
 120  * function will serve as the shared implementation for all of them,
 121  * <em>and additionally it will also override any non-abstract methods of
 122  * the same name</em>. This is done to be consistent with the fact that
 123  * ECMAScript does not have the concept of overloaded methods.
 124  *
 125  * <h2>The {@code Java} object</h2>
 126  *
 127  * Nashorn exposes a non-standard global object named {@code Java} that is
 128  * the primary API entry point into Java platform-specific functionality.
 129  * You can use it to create instances of Java classes, convert from Java arrays
 130  * to native arrays and back, and so on.
 131  *
 132  * <h2>Other non-standard built-in objects</h2>
 133  *
 134  * In addition to {@code Java}, Nashorn also exposes some other
 135  * non-standard built-in objects:
 136  * {@code JSAdapter}, {@code JavaImporter}, {@code Packages}
 137  *
 138  * @deprecated Nashorn JavaScript script engine and APIs, and the jjs tool
 139  * are deprecated with the intent to remove them in a future release.
 140  *
 141  * @provides javax.script.ScriptEngineFactory
 142  * @moduleGraph
 143  * @since 9
 144  */
 145 @Deprecated(since="11", forRemoval=true)
 146 module jdk.scripting.nashorn {
 147     requires java.logging;
 148     requires jdk.dynalink;
 149 
 150     requires transitive java.scripting;
 151 
 152     exports jdk.nashorn.api.scripting;
 153     exports jdk.nashorn.api.tree;
 154 
 155     exports jdk.nashorn.internal.runtime to
 156         jdk.scripting.nashorn.shell;
 157     exports jdk.nashorn.internal.objects to
 158         jdk.scripting.nashorn.shell;
 159     exports jdk.nashorn.tools to
 160         jdk.scripting.nashorn.shell;
 161 
 162     provides javax.script.ScriptEngineFactory with
 163         jdk.nashorn.api.scripting.NashornScriptEngineFactory;
 164 
 165     provides jdk.dynalink.linker.GuardingDynamicLinkerExporter with
 166         jdk.nashorn.api.linker.NashornLinkerExporter;
 167 }