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Class JSObject

java.lang.Object

netscape.javascript.JSObject

public abstract class JSObject extends Object

Allows Java code to manipulate JavaScript objects.

When a JavaScript object is passed or returned to Java code, it is wrapped in an instance of JSObject. When a JSObject instance is passed to the JavaScript engine, it is unwrapped back to its original JavaScript object. The JSObject class provides a way to invoke JavaScript methods and examine JavaScript properties.

Any data returned from the JavaScript engine to Java is converted to Java data types. Certain data passed to the JavaScript engine is converted to JavaScript data types.

Constructor Summary

JSObject()

Modifier	Constructor	Description
`protected`	Constructs a new JSObject.

Method Summary

Modifier and Type	Method	Description
`abstract Object`	`call(String methodName, Object... args)`	Calls a JavaScript method.
`abstract Object`	`eval(String s)`	Evaluates a JavaScript expression.
`abstract Object`	`getMember(String name)`	Retrieves a named member of a JavaScript object.
`abstract Object`	`getSlot(int index)`	Retrieves an indexed member of a JavaScript object.
`abstract void`	`removeMember(String name)`	Removes a named member of a JavaScript object.
`abstract void`	`setMember(String name, Object value)`	Sets a named member of a JavaScript object.
`abstract void`	`setSlot(int index, Object value)`	Sets an indexed member of a JavaScript object.

Methods declared in class java.lang.Object

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

Constructor Details

JSObject

protected JSObject()

Constructs a new JSObject. Users should neither call this method nor subclass JSObject.

Method Details

call

public abstract Object call(String methodName, Object... args) throws JSException

Calls a JavaScript method. Equivalent to "this.methodName(args[0], args[1], ...)" in JavaScript.

Parameters:: methodName - The name of the JavaScript method to be invoked.; args - the Java objects passed as arguments to the method.
Returns:: Result of the method.
Throws:: JSException - when an error is reported from the browser or JavaScript engine.

eval

public abstract Object eval(String s) throws JSException

Evaluates a JavaScript expression. The expression is a string of JavaScript source code which will be evaluated in the context given by "this".

Parameters:: s - The JavaScript expression.
Returns:: Result of the JavaScript evaluation.
Throws:: JSException - when an error is reported from the browser or JavaScript engine.

getMember

public abstract Object getMember(String name) throws JSException

Retrieves a named member of a JavaScript object. Equivalent to "this.name" in JavaScript.

Parameters:: name - The name of the JavaScript property to be accessed.
Returns:: The value of the property.
Throws:: JSException - when an error is reported from the browser or JavaScript engine.

setMember

public abstract void setMember(String name, Object value) throws JSException

Sets a named member of a JavaScript object. Equivalent to "this.name = value" in JavaScript.

Parameters:: name - The name of the JavaScript property to be accessed.; value - The value of the property.
Throws:: JSException - when an error is reported from the browser or JavaScript engine.

removeMember

public abstract void removeMember(String name) throws JSException

Removes a named member of a JavaScript object. Equivalent to "delete this.name" in JavaScript.

Parameters:: name - The name of the JavaScript property to be removed.
Throws:: JSException - when an error is reported from the browser or JavaScript engine.

getSlot

public abstract Object getSlot(int index) throws JSException

Retrieves an indexed member of a JavaScript object. Equivalent to "this[index]" in JavaScript.

Parameters:: index - The index of the array to be accessed.
Returns:: The value of the indexed member.
Throws:: JSException - when an error is reported from the browser or JavaScript engine.

setSlot

public abstract void setSlot(int index, Object value) throws JSException

Sets an indexed member of a JavaScript object. Equivalent to "this[index] = value" in JavaScript.

Parameters:: index - The index of the array to be accessed.; value - The value to set
Throws:: JSException - when an error is reported from the browser or JavaScript engine.

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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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https://docs.oracle.com/en/java/javase/21/docs/api/jdk.jsobject/netscape/javascript/JSObject.html