jdk/src/java.scripting/share/classes/javax/script/package.html
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+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
+<html>
+<head>
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+<body bgcolor="white">
+<p>The scripting API consists of interfaces and classes that define
+Java <font size=1><sup>TM</sup></font> Scripting Engines and provides
+a framework for their use in Java applications. This API is intended
+for use by application programmers who wish to execute programs
+written in scripting languages in their Java applications. The
+scripting language programs are usually provided by the end-users of
+the applications. 
+</p>
+<p>The main areas of functionality of <code>javax.script</code>
+package include 
+</p>
+<ol>
+	<li><p><b>Script execution</b>: Scripts
+	are streams of characters used as sources for  programs executed by
+	script engines. Script execution uses 
+        {@link javax.script.ScriptEngine#eval eval} methods of
+	{@link javax.script.ScriptEngine ScriptEngine} and methods of the 
+        {@link javax.script.Invocable Invocable} interface. 
+	</p>
+	<li><p><b>Binding</b>: This facility
+	allows Java objects to be exposed to script programs as named
+	variables. {@link javax.script.Bindings Bindings} and 
+        {@link javax.script.ScriptContext ScriptContext}
+	classes are used for this purpose. 
+	</p>
+	<li><p><b>Compilation</b>: This
+	functionality allows the intermediate code generated by the
+	front-end of a script engine to be stored and executed repeatedly.
+	This benefits applications that execute the same script multiple
+	times. These applications can gain efficiency since the engines'
+	front-ends only need to execute once per script rather than once per
+	script execution. Note that this functionality is optional and
+	script engines may choose not to implement it. Callers need to check
+	for availability of the {@link javax.script.Compilable Compilable}
+        interface using an <I>instanceof</I> check. 
+	</p>
+	<li><p><b>Invocation</b>: This
+	functionality allows the reuse of intermediate code generated by a
+	script engine's front-end. Whereas Compilation allows entire scripts
+	represented by intermediate code to be re-executed, Invocation
+	functionality allows individual procedures/methods in the scripts to
+	be re-executed. As in the case with compilation, not all script
+	engines are required to provide this facility. Caller has to check
+	for {@link javax.script.Invocable Invocable} availability. 
+	</p>
+	<li><p><b>Script engine discovery and Metadata</b>: Applications
+	written to the Scripting API might have specific requirements on
+	script engines. Some may require a specific scripting language
+	and/or version while others may require a specific implementation
+	engine and/or version. Script engines are packaged in a specified
+	way so that engines can be discovered at runtime and queried for
+	attributes. The Engine discovery mechanism is based on the Service
+	discovery mechanism described in the <b>Jar File Specification</b>.
+	Script engine implementing classes are packaged in jar files that
+	include a  text resource named
+	<b>META-INF/services/javax.script.ScriptEngineFactory</b>. This
+	resource must include a line for each 
+        {@link javax.script.ScriptEngineFactory ScriptEngineFactory}
+	that is packaged in the jar file. 
+        {@link javax.script.ScriptEngineManager ScriptEngineManager}
+	includes 
+        {@link javax.script.ScriptEngineManager#getEngineFactories getEngineFactories} method to get all
+	{@link javax.script.ScriptEngineFactory ScriptEngineFactory} instances 
+        discovered using this mechanism. <code>ScriptEngineFactory</code> has 
+        methods to query attributes about script engine.
+	</p>
+</ol>
+
+@since 1.6
+
+</body>
+</html>