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##Java, Cracked

import java.lang.reflect.*;
public class Main{
  public static void main(String... args){
    System.setOut(null);
    System.setErr(null);
    /*Your code here*/
  }
}

This should be was very easy to crack.

##Intended solution

import java.lang.reflect.*;
public class Main{
public static void main(String... args){
  System.setOut(null);
  System.setErr(null);
  try{
    Class<?> cistream = Class.forName("java.io.InputStream");
    Class<?> cfostream = Class.forName("java.io.FileOutputStream");
    Class<?> costream = Class.forName("java.io.OutputStream");
    Class<?> cfdescriptor = Class.forName("java.io.FileDescriptor");
    Object sout = cfostream.getConstructor(cfdescriptor).newInstance(cfdescriptor.getField("out").get(null));
    Class<?> csys = Class.forName("java.lang.System");
    Field mod = Field.class.getDeclaredField("modifiers");
    mod.setAccessible(true);
    Field stdout = csys.getField("out");
    mod.set(stdout,Integer.class.cast(mod.get(stdout) )&~ Modifier.FINAL);
    stdout.set(null,Class.forName("java.io.PrintStream").getConstructor(costream).newInstance(sout));
    Class<?> cscanner = Class.forName("java.util.Scanner");
    Object scanner = cscanner.getConstructor(cistream).newInstance(System.in);
    Method nextInt = cscanner.getMethod("nextInt");
    int f = Integer.class.cast(nextInt.invoke(scanner));
    int s = Integer.class.cast(nextInt.invoke(scanner));
    int sum = s + f;
    System.out.println(sum);
  }catch(Throwable t){t.printStackTrace();}
  }
}

Try it online