How to Make Reverse Object

Reversing an array of objects in Javascript

console.log() takes into account whether a mutable object has changed before it has been printed on the screen. And as your process of OUTPUT -> CHANGE -> OUTPUT is almost plesiochronous, both outputs are the same. You have to use a copy of x in order to get the prompt you need.

Try it this way:

// copy x
y = Object.assign({}, x);
console.log(y);

x.reverse();
console.log(x);

Reverse object hierarchy

You could use a recursive function to collect all the values. Then use reduce to create a nested object from the values:

const initObject = { 
  value: 5,
  next: {
   value: 10,
   next: {
     value: 15,
     next: null
   }
  }
}

const getValues = ({ value, next }) =>
  next 
    ? [value, ...getValues(next)] 
    : [value]

const createObject = values => 
  values.reduce((next, value) => ({ value, next }), null)

const output = createObject(getValues(initObject))

console.log(output)

Reverse object in jQuery.each

As it is, you can't in any reliable manner. Because you are enumerating an Object, there is never a guaranteed order.

If you want a guaranteed numeric order, you would need to use an Array, and iterate backwards.

EDIT: This will convert your Object to an Array, and do a reverse iteration.

Note that it will only work if all the properties are numeric.

var data = $.parseJSON($('#sdata').val());
var arr = [];

for( var name in data ) {
    arr[name] = data[name];
}
var len = arr.length;
while( len-- ) {
    if( arr[len] !== undefined ) {
        console.log(len,arr[len]);
    }
}

Reversing an Object.entries conversion

Sure, just use .reduce to assign to a new object:

const input = { key:'val', key2:'val2', key3:'val3' };
const output = Object.entries(input)  .filter(([k, v]) => {    return true; // some irrelevant conditions here  })  .reduce((accum, [k, v]) => {    accum[k] = v;    return accum;  }, {});console.log(output);

How can we get the objects in reverse order from list object?

Would Collections.reverse(list) work?