ScriptEngineFactory (Java SE 11 & JDK 11 ) (original) (raw)

All Known Implementing Classes:
[NashornScriptEngineFactory](../../../jdk.scripting.nashorn/jdk/nashorn/api/scripting/NashornScriptEngineFactory.html "class in jdk.nashorn.api.scripting")

public interface ScriptEngineFactory
ScriptEngineFactory is used to describe and instantiateScriptEngines.
Each class implementing ScriptEngine has a corresponding factory that exposes metadata describing the engine class.
The ScriptEngineManager uses the service-provider loader mechanism described in theServiceLoader class to obtain instances of ScriptEngineFactory instances. See ScriptEngineManager() andScriptEngineManager(java.lang.ClassLoader).
Since:
1.6

Method Summary

All Methods Instance Methods Abstract Methods

Modifier and Type	Method	Description
String	getEngineName()	Returns the full name of the ScriptEngine.
String	getEngineVersion()	Returns the version of the ScriptEngine.
List<String>	getExtensions()	Returns an immutable list of filename extensions, which generally identify scripts written in the language supported by this ScriptEngine.
String	getLanguageName()	Returns the name of the scripting language supported by thisScriptEngine.
String	getLanguageVersion()	Returns the version of the scripting language supported by thisScriptEngine.
String	getMethodCallSyntax(String obj,String m,String... args)	Returns a String which can be used to invoke a method of a Java object using the syntax of the supported scripting language.
List<String>	getMimeTypes()	Returns an immutable list of mimetypes, associated with scripts that can be executed by the engine.
List<String>	getNames()	Returns an immutable list of short names for the ScriptEngine, which may be used to identify the ScriptEngine by the ScriptEngineManager.
String	getOutputStatement(String toDisplay)	Returns a String that can be used as a statement to display the specified String using the syntax of the supported scripting language.
Object	getParameter(String key)	Returns the value of an attribute whose meaning may be implementation-specific.
String	getProgram(String... statements)	Returns a valid scripting language executable program with given statements.
ScriptEngine	getScriptEngine()	Returns an instance of the ScriptEngine associated with thisScriptEngineFactory.

Method Detail

 * #### getEngineName  
 [String](../../../java.base/java/lang/String.html "class in java.lang") getEngineName()  
 Returns the full name of the `ScriptEngine`. For instance an implementation based on the Mozilla Rhino Javascript engine might return _Rhino Mozilla Javascript Engine_.  
 Returns:  
 The name of the engine implementation.  
 * #### getEngineVersion  
 [String](../../../java.base/java/lang/String.html "class in java.lang") getEngineVersion()  
 Returns the version of the `ScriptEngine`.  
 Returns:  
 The `ScriptEngine` implementation version.  
 * #### getExtensions  
 [List](../../../java.base/java/util/List.html "interface in java.util")<[String](../../../java.base/java/lang/String.html "class in java.lang")> getExtensions()  
 Returns an immutable list of filename extensions, which generally identify scripts written in the language supported by this `ScriptEngine`. The array is used by the `ScriptEngineManager` to implement its`getEngineByExtension` method.  
 Returns:  
 The list of extensions.  
 * #### getMimeTypes  
 [List](../../../java.base/java/util/List.html "interface in java.util")<[String](../../../java.base/java/lang/String.html "class in java.lang")> getMimeTypes()  
 Returns an immutable list of mimetypes, associated with scripts that can be executed by the engine. The list is used by the`ScriptEngineManager` class to implement its`getEngineByMimetype` method.  
 Returns:  
 The list of mime types.  
 * #### getNames  
 [List](../../../java.base/java/util/List.html "interface in java.util")<[String](../../../java.base/java/lang/String.html "class in java.lang")> getNames()  
 Returns an immutable list of short names for the `ScriptEngine`, which may be used to identify the `ScriptEngine` by the `ScriptEngineManager`. For instance, an implementation based on the Mozilla Rhino Javascript engine might return list containing {"javascript", "rhino"}.  
 Returns:  
 an immutable list of short names  
 * #### getLanguageName  
 [String](../../../java.base/java/lang/String.html "class in java.lang") getLanguageName()  
 Returns the name of the scripting language supported by this`ScriptEngine`.  
 Returns:  
 The name of the supported language.  
 * #### getLanguageVersion  
 [String](../../../java.base/java/lang/String.html "class in java.lang") getLanguageVersion()  
 Returns the version of the scripting language supported by this`ScriptEngine`.  
 Returns:  
 The version of the supported language.  
 * #### getParameter  
 [Object](../../../java.base/java/lang/Object.html "class in java.lang") getParameter([String](../../../java.base/java/lang/String.html "class in java.lang") key)  
 Returns the value of an attribute whose meaning may be implementation-specific. Keys for which the value is defined in all implementations are:  
          * ScriptEngine.ENGINE  
          * ScriptEngine.ENGINE\_VERSION  
          * ScriptEngine.LANGUAGE  
          * ScriptEngine.LANGUAGE\_VERSION  
          * ScriptEngine.NAME  
  The values for these keys are the Strings returned by `getEngineName`,`getEngineVersion`, `getLanguageName`,`getLanguageVersion` for the first four keys respectively. For NAME, one of the Strings returned by `getNames` is returned.  
  A reserved key, `**THREADING**`, whose value describes the behavior of the engine with respect to concurrent execution of scripts and maintenance of state is also defined. These values for the `**THREADING**` key are:  
          * `null` \- The engine implementation is not thread safe, and cannot be used to execute scripts concurrently on multiple threads.  
          * `"MULTITHREADED"` \- The engine implementation is internally thread-safe and scripts may execute concurrently although effects of script execution on one thread may be visible to scripts on other threads.  
          * `"THREAD-ISOLATED"` \- The implementation satisfies the requirements of "MULTITHREADED", and also, the engine maintains independent values for symbols in scripts executing on different threads.  
          * `"STATELESS"` \- The implementation satisfies the requirements of`"THREAD-ISOLATED"`. In addition, script executions do not alter the mappings in the `Bindings` which is the engine scope of the`ScriptEngine`. In particular, the keys in the `Bindings` and their associated values are the same before and after the execution of the script.  
  Implementations may define implementation-specific keys.  
 Parameters:  
 `key` \- The name of the parameter  
 Returns:  
 The value for the given parameter. Returns `null` if no value is assigned to the key.  
 Throws:  
 `[NullPointerException](../../../java.base/java/lang/NullPointerException.html "class in java.lang")` \- if the key is null.  
 * #### getMethodCallSyntax  
 [String](../../../java.base/java/lang/String.html "class in java.lang") getMethodCallSyntax([String](../../../java.base/java/lang/String.html "class in java.lang") obj,  
                            [String](../../../java.base/java/lang/String.html "class in java.lang") m,  
                            [String](../../../java.base/java/lang/String.html "class in java.lang")... args)  
 Returns a String which can be used to invoke a method of a Java object using the syntax of the supported scripting language. For instance, an implementation for a Javascript engine might be;  
 `  
  public String getMethodCallSyntax(String obj,  
                                    String m, String... args) {  
       String ret = obj;  
       ret += "." + m + "(";  
       for (int i = 0; i < args.length; i++) {  
           ret += args[i];  
           if (i < args.length - 1) {  
               ret += ",";  
           }  
       }  
       ret += ")";  
       return ret;  
  }  
  `  
 Parameters:  
 `obj` \- The name representing the object whose method is to be invoked. The name is the one used to create bindings using the `put` method of`ScriptEngine`, the `put` method of an `ENGINE_SCOPE` `Bindings`,or the `setAttribute` method of `ScriptContext`. The identifier used in scripts may be a decorated form of the specified one.  
 `m` \- The name of the method to invoke.  
 `args` \- names of the arguments in the method call.  
 Returns:  
 The String used to invoke the method in the syntax of the scripting language.  
 Throws:  
 `[NullPointerException](../../../java.base/java/lang/NullPointerException.html "class in java.lang")` \- if obj or m or args or any of the elements of args is null.  
 * #### getOutputStatement  
 [String](../../../java.base/java/lang/String.html "class in java.lang") getOutputStatement([String](../../../java.base/java/lang/String.html "class in java.lang") toDisplay)  
 Returns a String that can be used as a statement to display the specified String using the syntax of the supported scripting language. For instance, the implementation for a Perl engine might be;  
 ```  
  public String getOutputStatement(String toDisplay) {  
       return "print(" + toDisplay + ")";  
  }  
        
 ```  
 Parameters:  
 `toDisplay` \- The String to be displayed by the returned statement.  
 Returns:  
 The string used to display the String in the syntax of the scripting language.  
 * #### getProgram  
 [String](../../../java.base/java/lang/String.html "class in java.lang") getProgram([String](../../../java.base/java/lang/String.html "class in java.lang")... statements)  
 Returns a valid scripting language executable program with given statements. For instance an implementation for a PHP engine might be:  
 ```  
  public String getProgram(String... statements) {  
       String retval = "<?\n";  
       int len = statements.length;  
       for (int i = 0; i < len; i++) {  
           retval += statements[i] + ";\n";  
       }  
       return retval += "?>";  
  }  
        
 ```  
 Parameters:  
 `statements` \- The statements to be executed. May be return values of calls to the `getMethodCallSyntax` and `getOutputStatement` methods.  
 Returns:  
 The Program  
 Throws:  
 `[NullPointerException](../../../java.base/java/lang/NullPointerException.html "class in java.lang")` \- if the `statements` array or any of its elements is null  
 * #### getScriptEngine  
 [ScriptEngine](ScriptEngine.html "interface in javax.script") getScriptEngine()  
 Returns an instance of the `ScriptEngine` associated with this`ScriptEngineFactory`. A new ScriptEngine is generally returned, but implementations may pool, share or reuse engines.  
 Returns:  
 A new `ScriptEngine` instance.

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ScriptEngineFactory (Java SE 11 & JDK 11 ) (original) (raw)

Method Summary

Method Detail