a * b + a - b; System.out.println("Private calculation: " + a + " * " + b + " + " + a + " - " + b + " = " + result); return result; } private void privateSetValue(String message, int number) { this.privateMessage = message; this.privateNumber = number; System.out.println("Private values updated: message='" + message + "', number=" + number); } private String privateComplexMethod(String[] words, boolean uppercase) { StringBuilder sb = new StringBuilder(); for (int i = 0; i < words.length; i++) { if (i > 0) sb.append(" "); sb.append(uppercase ? words[i].toUpperCase() : words[i].toLowerCase()); } String result = sb.toString(); System.out.println("Complex method processing: " + result); return result; } private static String privateStaticMethod(double value) { String formatted = String.format("%.2f", value); System.out.println("Static method processing: " + formatted); return "Processed: " + formatted; } いろんなメソッド用意しました