ptolemy.actor.lib.jjs

Class JSUtils

java.lang.Object

ptolemy.actor.lib.jjs.JSUtils

public class JSUtils
extends java.lang.Object

A collection of utilities for common procedures in the interaction between Java and JavaScript code through Nashorn.

Since:

Ptolemy II 11.0

Version:

$Id$

Author:

Marten Lohstroh

See Also:

ScriptObjectMirror

Constructor Summary

Constructors

Constructor and Description
JSUtils()

Method Summary

Modifier and Type	Method and Description
static <T> T	castSafely(java.lang.Object obj, java.lang.Class<T> objClass, boolean allowEmpty) Attempt to safely cast the given object into a given class.
static <T> boolean	checkSafety(java.lang.Object obj, java.lang.Class<T> objClass, boolean allowEmpty) Test whether a given object can be safely cast into a given class.
static <T> boolean	isSafe(java.lang.Object obj, java.lang.Class<T> objClass) Test whether a given object can be safely cast into a given class.
static <T> boolean	isSafeNotEmpty(java.lang.Object obj, java.lang.Class<T> objClass) Test whether a given object can be safely cast into a given class.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

JSUtils

public JSUtils()

Method Detail

castSafely

public static <T> T castSafely(java.lang.Object obj,
                               java.lang.Class<T> objClass,
                               boolean allowEmpty)

Attempt to safely cast the given object into a given class. If the object is null, then the cast is considered unsafe. Additionally, if the argument allowEmpty is set to false, then only consider the cast safe if the object is not empty. If the cast is safe, return the object, return null otherwise. Note that no ClassCastException is thrown by this method. If the cast fails, it returns null.

Parameters:

obj - The object to be cast.

objClass - The class to cast the object to.

allowEmpty - Whether empty objects are desired.

Returns:

The object if the cast is successful, null otherwise.

isSafe

public static <T> boolean isSafe(java.lang.Object obj,
                                 java.lang.Class<T> objClass)

Test whether a given object can be safely cast into a given class. If the object is null, then the cast is considered unsafe. If the cast is safe, return true, return false otherwise. Note that no ClassCastException is thrown by this method. If the cast fails, it returns false.

Parameters:

obj - The object to be cast.

objClass - The class to cast the object to.

Returns:

True if the cast is successful, false otherwise.

isSafeNotEmpty

public static <T> boolean isSafeNotEmpty(java.lang.Object obj,
                                         java.lang.Class<T> objClass)

Test whether a given object can be safely cast into a given class. If the object is null, then the cast is considered unsafe. Moreover, only if the object is not empty the cast is considered safe. If the cast is safe, return true, return false otherwise. Note that no ClassCastException is thrown by this method. If the cast fails, it returns false.

Parameters:

obj - The object to be cast.

objClass - The class to cast the object to.

Returns:

True if the cast is successful, false otherwise.

checkSafety

public static <T> boolean checkSafety(java.lang.Object obj,
                                      java.lang.Class<T> objClass,
                                      boolean allowEmpty)

Test whether a given object can be safely cast into a given class. If the object is null, then the cast is considered unsafe. Additionally, if the argument allowEmpty is set to false, then only consider the cast safe if the object is not empty. If the cast is safe, return true, return false otherwise. Note that no ClassCastException is thrown by this method. If the cast fails, it returns false.

Parameters:

obj - The object to be cast.

objClass - The class to cast the object to.

allowEmpty - Whether empty objects are desired.

Returns:

True if the cast is successful, false otherwise.