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The Alphabets class provides a set of predefined character strings that can be used with validation rules like shouldOnlyContain, notContain, and mustContainOne. These constants make it easy to validate that input contains only specific types of characters.

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Import

import io.github.ApamateSoft.validator.utils.Alphabets;

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Available Alphabets

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Numeric Systems

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BIN

Binary digits (base-2) 
Alphabets.BIN = "01"
Example: 
Validator validator = new Validator.Builder()
    .shouldOnlyContain(Alphabets.BIN, "Must contain only binary digits")
    .build();

validator.isValid("101010"); // Valid
validator.isValid("102");    // Invalid - contains '2'

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OCT

Octal digits (base-8) 
Alphabets.OCT = "01234567"
Example: 
Validator validator = new Validator.Builder()
    .shouldOnlyContain(Alphabets.OCT, "Must contain only octal digits")
    .build();

validator.isValid("755");  // Valid
validator.isValid("789");  // Invalid - contains '8' and '9'

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HEX

Hexadecimal digits (base-16) 
Alphabets.HEX = "0123456789aAbBcCdDeEfF"
Example: 
Validator validator = new Validator.Builder()
    .shouldOnlyContain(Alphabets.HEX, "Must contain only hexadecimal digits")
    .build();

validator.isValid("1a2B3c");  // Valid
validator.isValid("GGFF00");  // Invalid - contains 'G'

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English Alphabets

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NUMBER

Numeric digits (0-9) 
Alphabets.NUMBER = "0123456789"
Example: 
Validator validator = new Validator.Builder()
    .shouldOnlyContain(Alphabets.NUMBER, "Must contain only numbers")
    .build();

validator.isValid("12345");     // Valid
validator.isValid("12-345");    // Invalid - contains '-'

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ALPHABET

English letters (mixed case) 
Alphabets.ALPHABET = "aAbBcCdDeEfFgGhHiIjJkKlLmMnNoOpPqQrRsStTuUvVwWxXyYzZ"
Example: 
Validator validator = new Validator.Builder()
    .shouldOnlyContain(Alphabets.ALPHABET, "Must contain only letters")
    .build();

validator.isValid("JohnDoe");   // Valid
validator.isValid("John123");   // Invalid - contains numbers

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ALPHA_LOWERCASE

Lowercase English letters 
Alphabets.ALPHA_LOWERCASE = "abcdefghijklmnopqrstuvwxyz"
Example: 
Validator validator = new Validator.Builder()
    .shouldOnlyContain(Alphabets.ALPHA_LOWERCASE, "Must contain only lowercase letters")
    .build();

validator.isValid("johndoe");  // Valid
validator.isValid("JohnDoe");  // Invalid - contains uppercase

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ALPHA_UPPERCASE

Uppercase English letters 
Alphabets.ALPHA_UPPERCASE = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
Example: 
Validator validator = new Validator.Builder()
    .shouldOnlyContain(Alphabets.ALPHA_UPPERCASE, "Must contain only uppercase letters")
    .build();

validator.isValid("ABCD");    // Valid
validator.isValid("AbCd");    // Invalid - contains lowercase

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ALPHA_NUMERIC

English letters and numbers 
Alphabets.ALPHA_NUMERIC = "0123456789aAbBcCdDeEfFgGhHiIjJkKlLmMnNoOpPqQrRsStTuUvVwWxXyYzZ"
Example: 
Validator validator = new Validator.Builder()
    .shouldOnlyContain(Alphabets.ALPHA_NUMERIC, "Must contain only letters and numbers")
    .build();

validator.isValid("User123");    // Valid
validator.isValid("User_123");   // Invalid - contains '_'

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Spanish Alphabets

These alphabets include Spanish-specific characters like ñ, á, é, í, ó, ú.

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ALPHABET_ES

Spanish letters (mixed case) with accents 
Alphabets.ALPHABET_ES = "aAáÁbBcCdDeEéÉfFgGhHiIíÍjJkKlLmMnNñÑoOóÓpPqQrRsStTuUúÚvVwWxXyYzZ"
Example: 
Validator validator = new Validator.Builder()
    .shouldOnlyContain(Alphabets.ALPHABET_ES, "Must contain only Spanish letters")
    .build();

validator.isValid("José");        // Valid
validator.isValid("Peña");        // Valid
validator.isValid("José123");     // Invalid - contains numbers

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ALPHA_LOWERCASE_ES

Lowercase Spanish letters with accents 
Alphabets.ALPHA_LOWERCASE_ES = "aábcdeéfghiíjklmnñoópqrstuúvwxyz"
Example: 
Validator validator = new Validator.Builder()
    .shouldOnlyContain(Alphabets.ALPHA_LOWERCASE_ES, "Must contain only lowercase Spanish letters")
    .build();

validator.isValid("josé");    // Valid
validator.isValid("José");    // Invalid - contains uppercase

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ALPHA_UPPERCASE_ES

Uppercase Spanish letters with accents 
Alphabets.ALPHA_UPPERCASE_ES = "AÁBCDEÉFGHIÍJKLMNÑOÓPQRSTUÚVWXYZ"
Example: 
Validator validator = new Validator.Builder()
    .shouldOnlyContain(Alphabets.ALPHA_UPPERCASE_ES, "Must contain only uppercase Spanish letters")
    .build();

validator.isValid("JOSÉ");    // Valid
validator.isValid("José");    // Invalid - contains lowercase

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ALPHA_NUMERIC_ES

Spanish letters (with accents) and numbers 
Alphabets.ALPHA_NUMERIC_ES = "0123456789aAáÁbBcCdDeEéÉfFgGhHiIíÍjJkKlLmMnNñÑoOóÓpPqQrRsStTuUúÚvVwWxXyYzZ"
Example: 
Validator validator = new Validator.Builder()
    .shouldOnlyContain(Alphabets.ALPHA_NUMERIC_ES, "Must contain only Spanish letters and numbers")
    .build();

validator.isValid("Código123");   // Valid
validator.isValid("Code-123");    // Invalid - contains '-'

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Usage with Validation Rules

Alphabets are most commonly used with these validation rules:

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shouldOnlyContain

Validate that input contains only characters from the alphabet: 
Validator passwordValidator = new Validator()
    .shouldOnlyContain(Alphabets.ALPHA_NUMERIC + "_-", "Password must contain only letters, numbers, hyphens, and underscores")
    .build();

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notContain

Validate that input does not contain any characters from the alphabet: 
Validator usernameValidator = new Validator()
    .notContain("!@#$%^&*()", "Username cannot contain special characters");

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mustContainOne

Validate that input contains at least one character from the alphabet: 
Validator passwordValidator = new Validator()
    .mustContainOne(Alphabets.NUMBER, "Password must contain at least one number")
    .mustContainOne(Alphabets.ALPHA_UPPERCASE, "Password must contain at least one uppercase letter");

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mustContainMin

Validate that input contains a minimum number of characters from the alphabet: 
Validator passwordValidator = new Validator()
    .mustContainMin(2, Alphabets.NUMBER, "Password must contain at least 2 numbers");

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Custom Alphabets

You can also create your own custom alphabets for specific validation needs: 
// Custom alphabet for vowels only
String vowels = "aeiouAEIOU";
Validator validator = new Validator.Builder()
    .shouldOnlyContain(vowels, "Must contain only vowels")
    .build();

// Custom alphabet for common safe URL characters
String urlSafe = Alphabets.ALPHA_NUMERIC + "-._~";
Validator urlValidator = new Validator()
    .shouldOnlyContain(urlSafe, "Must be URL-safe")
    .build();

// Custom alphabet combining multiple predefined sets
String passwordChars = Alphabets.ALPHA_NUMERIC + "!@#$%^&*()";
Validator passwordValidator = new Validator()
    .shouldOnlyContain(passwordChars, "Password contains invalid characters")
    .build();

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Use Cases

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Password Validation

Validator passwordValidator = new Validator()
    .required("Password is required")
    .minLength(8, "Password must be at least 8 characters")
    .mustContainOne(Alphabets.ALPHA_LOWERCASE, "Must contain a lowercase letter")
    .mustContainOne(Alphabets.ALPHA_UPPERCASE, "Must contain an uppercase letter")
    .mustContainOne(Alphabets.NUMBER, "Must contain a number")
    .mustContainOne("!@#$%^&*()", "Must contain a special character");

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Username Validation

Validator usernameValidator = new Validator()
    .required("Username is required")
    .rangeLength(3, 20, "Username must be 3-20 characters")
    .shouldOnlyContain(Alphabets.ALPHA_NUMERIC + "_", "Username can only contain letters, numbers, and underscores")
    .notContain(Alphabets.ALPHA_UPPERCASE, "Username must be lowercase");

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Color Hex Code Validation

Validator hexColorValidator = new Validator()
    .required("Color code is required")
    .length(6, "Color code must be exactly 6 characters")
    .shouldOnlyContain(Alphabets.HEX, "Must be a valid hexadecimal color code")
    .build();

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Spanish Name Validation

Validator nombreValidator = new Validator()
    .required("Nombre es requerido")
    .shouldOnlyContain(Alphabets.ALPHABET_ES + " ", "El nombre solo puede contener letras españolas y espacios")
    .build();

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