apktool d sample.apk 

.class public Landroid/support/a/c/a;
.super Ljava/lang/Object;


# direct methods
.method public static a()Z
    .locals 2

    sget v0, Landroid/os/Build$VERSION;->SDK_INT:I

    const/16 v1, 0x18

    if-lt v0, v1, :cond_0

    const/4 v0, 0x1

    goto :goto_0

    :cond_0
    const/4 v0, 0x0

    :goto_0
    return v0
.end method

Z -> boolean
B -> byte
S -> short
C -> char
I -> int
J -> long (64 bits)
F -> float
D -> double (64 bits)

[B -> byte[] 

L + package_name.replace('.','/') + class_name + ';'
Ex : String -> Ljava/lang/String;

outerclass_notation + '$' + class_name
Ex : com.sample.Voiture.Pneu -> Lcom/sample/Voiture$Pneu;

Lpackage/name/ObjectName;->MethodName(III)Z

.class public LHelloWorld;
.super Ljava/lang/Object;

.method public static main([Ljava/lang/String;)V
    .registers 2

    sget-object v0, Ljava/lang/System;->out:Ljava/io/PrintStream;

    const-string	v1, "Hello World!"

    invoke-virtual {v0, v1}, Ljava/io/PrintStream;->println(Ljava/lang/String;)V

    return-void
.end method

public class HelloWorld extends Object{
	public static main(String args[]){
    	System.out.println("Hello World!");
    }
}

URLClassLoader child = new URLClassLoader(
        new URL[] {myJar.toURI().toURL()},
        this.getClass().getClassLoader()
);
Class classToLoad = Class.forName("com.MyClass", true, child);
Method method = classToLoad.getDeclaredMethod("myMethod");
Object instance = classToLoad.newInstance();
Object result = method.invoke(instance);

➜  apktool d exemple.apk
I: Using Apktool 2.4.0-29355f-SNAPSHOT on exemple.apk
I: Loading resource table...
I: Decoding AndroidManifest.xml with resources...
S: WARNING: Could not write to (/home/romain/.local/share/apktool/framework), using /tmp 
instead...
S: Please be aware this is a volatile directory and frameworks could go missing, 
please utilize --frame-path if the default storage directory is unavailable
I: Loading resource table from file: /tmp/1.apk
I: Regular manifest package...
I: Decoding file-resources...
I: Decoding values */* XMLs...
I: Baksmaling classes.dex...
I: Copying assets and libs...
I: Copying unknown files...
I: Copying original files...


➜  grep -lre "Oh no" exemple
exemple/smali/areizen/antiemulator/myapplication/MainActivity.smali

 .line 45
invoke-virtual {p0, p0}, Lareizen/antiemulator/myapplication/MainActivity;
	->antiemulation(Landroid/content/Context;)Z

move-result p1

const-string v0, "Anti-emulation"

if-eqz p1, :cond_0

const-string p1, "Oh no ! It\'s an emulator :("

if-eqz p1, :cond_0

if-nez p1, :cond_0

apktool b example -o repackaged.apk

java -jar sign.jar repackaged.apk

Java.perform(function(){
  
    // On recupère la classe String
    const String = Java.use('java.lang.String');
    
    // On va affiche dés qu'une chaine est comparée
    String.equals.implementation = function(x){
    	console.log(this.toString() + ' == ' + x.toString())
    	return this.equals(x)
    }
    
})

pip install frida-tools
pip install frida-push

frida-push # Push the Frida Server to the emulator / device

Java.perform(function(){
	
    
    
    
    
    // Basic template
    
    
    
    
 
})

Java.perform(function(){
	
    const MainActivity = Java.use("areizen.antiemulator.myapplication.MainActivity")
    
    MainActivity.antiemulation.implementation = function(x){
        console.log("Bypassed Anti-emulator")
    	return false;
    }
})

frida -U -l script.js -f areizen.antiemulator.myapplication --no-pause

Java.perform(function(){
    
    const Log = Java.use("android.util.Log")
    const System = Java.use("java.lang.System")

    var tsLong = System.currentTimeMillis()/1000;
    var timestamp = tsLong.toString();

    Log.i("Timestamp", "Printing timestamp from Frida :" + timestamp)

})

static {
	// Will load libexample.so
	System.loadLibrary("example"); 
}

public native String helloWorld();

JNIEXPORT jstring JNICALL
Java_com_google_sample_helloandroidjni_MainActivity_helloWorld(JNIEnv* env);

Interceptor.attach(null, "strlen",{
	onEnter: function(args){
    	console.log("strlen called on : " + Memory.readCString(args[0]));
    }
})