How to Create a instance for android?

[mutepigz]

I face a problem that I want to call a function but it belongs to a class
I tried code like

var Class = Java.use("com.test.Main");                                                                                                                      
Class.function("123");

but it error

cannot call instance method without an instance

so how to create a instance for android?

[Oreaz]

https://www.frida.re/docs/javascript-api/#java

Java.use(className): dynamically get a JavaScript wrapper for className that you can instantiate objects from by calling $new() on it to invoke a constructor.

Another example

Java.perform(function () {
	var stringClass = Java.use("java.lang.String");
	var stringInstance = stringClass.$new("Hello World");
	send(stringInstance.toString());
});

basically in the example code it's the equivalent of
new String("Hello World") in Java
https://developer.android.com/reference/java/lang/String.html

[royhershkovitz]

checkout this
https://android.jlelse.eu/hacking-android-app-with-frida-a85516f4f8b7