Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;

public class Main {
    private static String deriveLongerString(String str) {
        StringBuilder sb = new StringBuilder(str);
        StringBuilder builder = new StringBuilder();
        builder.append(sb.toString().toLowerCase());
        builder.append(sb.toString().toUpperCase());
        StringBuilder result = new StringBuilder();
        result.append(sb);
        result.append(mix(builder.toString()));
        result.append(mix(builder.reverse().toString()));
        return result.toString();
    }

    private static String mix(String str) {
        String result = str;
        String holder;
        int iters = str.length() / 4;
        for (int i = 0; i < iters; i++) {
            holder = mixStep(result);
            result = holder;
        }
        return result;
    }

    private static String mixStep(String str) {
        if (str == null || str.isEmpty()) {
            return "";
        }
        if (str.length() == 1) {
            return str;
        }
        if (str.length() == 2) {
            StringBuilder sb = new StringBuilder(str);
            return sb.reverse().toString();
        }
        StringBuilder sb = new StringBuilder();
        String char1 = String.valueOf(str.charAt(0));
        String char2 = String.valueOf(str.charAt(1));
        String char3 = String.valueOf(str.charAt(2));
        if ((char1.compareTo(char2) > 0) && (char1.compareTo(char3) < 0)) {
            return sb.append(mixStep(str.substring(2))).append(str.charAt(1)).append(str.charAt(0)).toString();
        } else if ((char1.compareTo(char2) > 0) && (char1.compareTo(char3) > 0)) {
            String mixReverse = (new StringBuilder(mixStep(str.substring(2)))).reverse().toString();
            return sb.append(str.charAt(1)).append(mixReverse).append(str.charAt(0)).toString();
        } else if ((char1.compareTo(char2) < 0) && (char1.compareTo(char3) > 0)) {
            return sb.append(str.charAt(0)).append(mixStep(str.substring(2))).append(str.charAt(1)).toString();
        } else if ((char1.compareTo(char2) < 0) && (char1.compareTo(char3) < 0)) {
            String mixReverse = (new StringBuilder(mixStep(str.substring(2)))).reverse().toString();
            return sb.append(str.charAt(0)).append(mixReverse).append(str.charAt(1)).toString();
        }
        return sb.append(str.charAt(1)).append(str.charAt(0)).append(mixStep(str.substring(2))).toString();
    }
}