java thing

package main;

import java.util.Arrays;
import java.util.Scanner;

public class Guesser {

    public static String[] illegalChars = new String[] { "{", "}", "(", ")", "[", "]" };

    public static String currentEquation = "4 + (7 * 7)";

    public static void main(String[] args) {
        String[] splitEQ = currentEquation.split(" ");
        for (int i = 0 ; i < splitEQ.length ; i++) {
            if (splitEQ[i].equals("*")) {

                int indexer = i;
                while (Arrays.stream(illegalChars).parallel().anyMatch(splitEQ[indexer-1]::contains) && indexer-1 != 0) { System.out.println("Found illegal char at "+(indexer-1)+" with value "+splitEQ[indexer-1]); indexer -= 2; }
                splitEQ[indexer-1] = "{" + splitEQ[indexer-1];
                indexer = i;
                while (Arrays.stream(illegalChars).parallel().anyMatch(splitEQ[indexer+1]::contains) && indexer+2 < splitEQ.length) { System.out.println("Found illegal char at "+(indexer+1)+" with value "+splitEQ[indexer+1]); indexer += 2; }
                splitEQ[indexer+1] = splitEQ[indexer+1] + "}";

                for (int x = 0 ; x < splitEQ.length ; x++) {
                    System.out.println(splitEQ[x]+"       INDEX "+x);
                }

            }  else if (splitEQ[i].equals("/")) {

                int indexer = i;
                while (Arrays.stream(illegalChars).parallel().anyMatch(splitEQ[indexer-1]::contains) && indexer-1 != 0) { System.out.println("Found illegal char at "+(indexer-1)+" with value "+splitEQ[indexer-1]); indexer -= 2; }
                splitEQ[indexer-1] = "{" + splitEQ[indexer-1];
                indexer = i;
                while (Arrays.stream(illegalChars).parallel().anyMatch(splitEQ[indexer+1]::contains) && indexer+2 < splitEQ.length) { System.out.println("Found illegal char at "+(indexer+1)+" with value "+splitEQ[indexer+1]); indexer += 2; }
                splitEQ[indexer+1] = splitEQ[indexer+1] + "}";

                for (int x = 0 ; x < splitEQ.length ; x++) {
                    System.out.println(splitEQ[x]+"       INDEX "+x);
                }

            } else if (splitEQ[i].equals("+")) {

                int indexer = i;
                while (Arrays.stream(illegalChars).parallel().anyMatch(splitEQ[indexer-1]::contains) && indexer-1 != 0) { System.out.println("Found illegal char at "+(indexer-1)+" with value "+splitEQ[indexer-1]); indexer -= 2; }
                splitEQ[indexer-1] = "{" + splitEQ[indexer-1];
                indexer = i;
                while (Arrays.stream(illegalChars).parallel().anyMatch(splitEQ[indexer+1]::contains) && indexer+2 < splitEQ.length) { System.out.println("Found illegal char at "+(indexer+1)+" with value "+splitEQ[indexer+1]); indexer += 2; }
                splitEQ[indexer+1] = splitEQ[indexer+1] + "}";

                for (int x = 0 ; x < splitEQ.length ; x++) {
                    System.out.println(splitEQ[x]+"       INDEX "+x);
                }

            } else if (splitEQ[i].equals("-")) {

                int indexer = i;
                while (Arrays.stream(illegalChars).parallel().anyMatch(splitEQ[indexer-1]::contains) && indexer-1 != 0) { System.out.println("Found illegal char at "+(indexer-1)+" with value "+splitEQ[indexer-1]); indexer -= 2; }
                splitEQ[indexer-1] = "{" + splitEQ[indexer-1];
                indexer = i;
                while (Arrays.stream(illegalChars).parallel().anyMatch(splitEQ[indexer+1]::contains) && indexer+2 < splitEQ.length) { System.out.println("Found illegal char at "+(indexer+1)+" with value "+splitEQ[indexer+1]); indexer += 2; }
                splitEQ[indexer+1] = splitEQ[indexer+1] + "}";

                for (int x = 0 ; x < splitEQ.length ; x++) {
                    System.out.println(splitEQ[x]+"       INDEX "+x);
                }

            }
        }

        String output = "";
        for (int i = 0 ; i < splitEQ.length ; i++) {
            output = output + splitEQ[i] + " ";
        }
        System.out.println(output);

    }

}