/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
 
		/*
		 * Retorno que iremos trabalhar 
		 */
		final String retorno = "Sucesso! Usuario salvo. Id: 257";
 
		// Pegamos a posição do : na String
		int posicaoDoisPontos = retorno.indexOf(':');
 
		// Caso ão ache os : na STring irá retornar -1
		if(posicaoDoisPontos > -1){
			// Vamos pegar a psoição a frente do : até o fim da String (seu tamanho)
			String idLiteral =  retorno.substring( (posicaoDoisPontos+1) , retorno.length() );
			// Transformamos a String em Integer
			Integer id = Integer.valueOf(idLiteral.trim());
			System.out.println(id);
		}else{
			System.out.println("Não foi possível formatar o valor!");
		}
	}
}

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