My stupid JsonFormatter

JsonFormatter.java

/**
 * Format a JSON string and make it more readable
 * Created by kshang on 20/04/2017.
 */
public class JsonFormatter {

  public String format(String input) {
    StringBuilder sb = new StringBuilder();
    char[] chars = input.toCharArray();
    boolean inQuote = false;
    boolean newLine = true;
    int level = 0;
    Character close = null;
    for (int i = 0; i < chars.length; i++) {
      // Ignore white spaces
      if (!inQuote && Character.isWhitespace(chars[i])) continue;

      // Indentation for new line
      if (newLine) {
        newLine = false;
        for (int j = 0; j < level; j++) {
          sb.append('\t');
        }
      }

      if (close != null) {
        sb.append(close);
        close = null;
      }

      switch (chars[i]) {
        // break line
        case ',':
          sb.append(chars[i]);
          if (!inQuote) {
            sb.append("\n");
            newLine = true;
          }
          break;
        // check whether inQuote
        case '"':
          sb.append(chars[i]);
          inQuote = !inQuote;
          break;
        // object or array, add increment indentation
        case '[':
        case '{':
          sb.append(chars[i]);
          if (!inQuote) {
            sb.append("\n");
            newLine = true;
            level++;
          }
          break;
        case ']':
        case '}':
          // buffer the close bracket and curly brace
          close = chars[i];
          if (!inQuote) {
            sb.append("\n");
            newLine = true;
            level--;
          }
          break;
        default:
          sb.append(chars[i]);
      }
    }

    // last close bracket or curly brace
    if (close != null) {
      sb.append(close);
    }
    return sb.toString();
  }
}