public class CaesarEncryption { int shift = 13; public String getEncryptedMessage(String msg) { StringBuilder builder = new StringBuilder(); for (int i = 0, size = msg.length(); i < size; ++i) builder.append((char) (msg.charAt(i) + shift)); return builder.toString(); } public String getDecryptedMessage(String msg) { StringBuilder builder = new StringBuilder(); for (int i = 0, size = msg.length(); i < size; ++i) builder.append((char) (msg.charAt(i) - shift)); return builder.toString(); } }