Class Utils

java.lang.Object
com.erudika.para.core.utils.Utils
public final class Utils extends Object
Miscellaneous Para utilities.
Author:
Alex Bogdanovski [[email protected]]

  • Method Details

    • getInstance

      public static Utils getInstance()
      Returns an instance of this class.
      Returns:
      an instance

    • getHumanTime

      public static HumanTime getHumanTime()
      HumanTime - a relative time formatter.
      Returns:
      humantime instance

    • md5

      public static String md5(String s)
      md5 hash function.
      Parameters:
      s - the string to be hashed
      Returns:
      an md5 hash

    • hmacSHA256

      public static String hmacSHA256(String message, String secret)
      Computes the HmacSHA256 hash of a message.
      Parameters:
      message - a message as UTF-8 encoded string
      secret - a secret key
      Returns:
      base64(hmacSHA256(message, secret))

    • bcrypt

      public static String bcrypt(String s)
      bcrypt hash function implemented by Spring Security.
      Parameters:
      s - the string to be hashed
      Returns:
      the hash

    • bcryptMatches

      public static boolean bcryptMatches(String plain, String storedHash)
      Checks if a hash matches a string.
      Parameters:
      plain - plain text string
      storedHash - hashed string
      Returns:
      true if the hash matches

    • generateSecurityToken

      public static String generateSecurityToken(int length, boolean urlSafe)
      Generates an authentication token - a random string encoded in Base64.
      Parameters:
      length - the length of the generated token
      urlSafe - switches to a URL safe encoding
      Returns:
      a random string

    • generateSecurityToken

      public static String generateSecurityToken(int length)
      Generates an authentication token - a random string encoded in Base64.
      Parameters:
      length - the length of the generated token
      Returns:
      a random string

    • generateSecurityToken

      public static String generateSecurityToken()
      Generates an authentication token - a random 32 byte string encoded in Base64.
      Returns:
      a random string

    • stripHtml

      public static String stripHtml(String html)
      Strips all HTML tags from a string.
      Parameters:
      html - HTML string
      Returns:
      just the text

    • markdownToHtml

      public static String markdownToHtml(String markdownString)
      Converts Markdown to HTML.
      Parameters:
      markdownString - Markdown
      Returns:
      HTML

    • markdownToHtml

      public static String markdownToHtml(String markdownString, boolean htmlTagsRenderingEnabled)
      Converts Markdown to HTML.
      Parameters:
      markdownString - Markdown
      htmlTagsRenderingEnabled - if true, basic HTML tags will be rendered instead of escaped
      Returns:
      HTML

    • compileMustache

      public static String compileMustache(Map<String,Object> context, String template, boolean escapeHtml)
      Compiles a mustache template with a given scope (map of fields and values).
      Parameters:
      context - a map of fields and values
      template - a Mustache template
      escapeHtml - enable/disable escaping of HTML
      Returns:
      the compiled template string

    • compileMustache

      public static String compileMustache(Map<String,Object> context, String template)
      Parameters:
      context - a map of fields and values
      template - a Mustache template
      Returns:
      the compiled template string
      See Also:

    • abbreviate

      public static String abbreviate(String str, int max)
      Abbreviates a string.
      Parameters:
      str - a string
      max - max length
      Returns:
      a substring of that string

    • arrayJoin

      public static String arrayJoin(List<String> arr, String separator)
      Joins a list of strings to String using a separator.
      Parameters:
      arr - a list of strings
      separator - a separator string
      Returns:
      a string

    • stripAndTrim

      public static String stripAndTrim(String str)
      Strips all symbols, punctuation, whitespace and control chars from a string.
      Parameters:
      str - a dirty string
      Returns:
      a clean string

    • stripAndTrim

      public static String stripAndTrim(String str, String replaceWith)
      Strips all symbols, punctuation, whitespace and control chars from a string.
      Parameters:
      str - a dirty string
      replaceWith - a string to replace spaces with
      Returns:
      a clean string

    • stripAndTrim

      public static String stripAndTrim(String str, String replaceWith, boolean asciiOnly)
      Strips all symbols, punctuation, whitespace and control chars from a string.
      Parameters:
      str - a dirty string
      replaceWith - a string to replace spaces with
      asciiOnly - if true, all non-ASCII characters will be stripped
      Returns:
      a clean string

    • noSpaces

      public static String noSpaces(String str, String replaceWith)
      Converts spaces to dashes.
      Parameters:
      str - a string with spaces
      replaceWith - a string to replace spaces with
      Returns:
      a string with dashes

    • formatMessage

      public static String formatMessage(String msg, Object... params)
      Formats a messages containing {0}, {1}... etc. Used for translation.
      Parameters:
      msg - a message with placeholders
      params - objects used to populate the placeholders
      Returns:
      a formatted message

    • base64enc

      public static String base64enc(byte[] str)
      Encodes a byte array to Base64.
      Parameters:
      str - the byte array
      Returns:
      an encoded string

    • base64encURL

      public static String base64encURL(byte[] str)
      Encodes a byte array to Base64. URL safe.
      Parameters:
      str - the byte array
      Returns:
      an encoded string

    • base64dec

      public static String base64dec(String str)
      Decodes a string from Base64.
      Parameters:
      str - the encoded string
      Returns:
      a decoded string

    • formatDate

      public static String formatDate(Long timestamp, String format, Locale loc)
      Formats a date in a specific format.
      Parameters:
      timestamp - the Java timestamp
      format - the date format
      loc - the locale instance
      Returns:
      a formatted date

    • formatDate

      public static String formatDate(String format, Locale loc)
      Formats the date for today, in a specific format.
      Parameters:
      format - the date format
      loc - the locale instance
      Returns:
      today's date formatted

    • getCurrentYear

      public static int getCurrentYear()
      Returns the current year.
      Returns:
      this year

    • timestamp

      public static long timestamp()
      Java timestamp.
      Returns:
      System.currentTimeMillis()

    • getMonths

      public static String[] getMonths(Locale locale)
      Returns an array of the months in the Gregorian calendar.
      Parameters:
      locale - the locale used for the months' names
      Returns:
      an array of the 12 months

    • getLocale

      public static Locale getLocale(String localeStr)
      Parameters:
      localeStr - locale string
      Returns:
      a Locale instance from a locale string.

    • round

      public static int round(float d)
      Rounds a float to an int.
      Parameters:
      d - a float
      Returns:
      a rounded int

    • formatPrice

      public static String formatPrice(double price)
      Returns the price with two fractional digits at the end.
      Parameters:
      price - a price
      Returns:
      $###.##

    • roundHalfUp

      public static double roundHalfUp(double d)
      Round up a double using the "half up" method.
      Parameters:
      d - a double
      Returns:
      a double

    • roundHalfUp

      public static double roundHalfUp(double d, int scale)
      Round up a double using the "half up" method.
      Parameters:
      d - a double
      scale - the scale
      Returns:
      a double

    • abbreviateInt

      public static String abbreviateInt(Number number, int decPlaces)
      Abbreviates an integer by adding a letter suffix at the end. E.g. "M" for millions, "K" for thousands, etc.
      Parameters:
      number - a big integer
      decPlaces - decimal places
      Returns:
      the rounded integer as a string

    • urlDecode

      public static String urlDecode(String s)
      Decodes a URL-encoded string.
      Parameters:
      s - a string
      Returns:
      the decoded string

    • urlEncode

      public static String urlEncode(String s)
      URL-encodes a string.
      Parameters:
      s - a string
      Returns:
      the encoded string

    • isValidURL

      public static boolean isValidURL(String url)
      URL validation.
      Parameters:
      url - a URL
      Returns:
      true if the URL is valid

    • isValidEmail

      public static boolean isValidEmail(String email)
      Email validation.
      Parameters:
      email - email address
      Returns:
      true if the URL is valid

    • getHostFromURL

      public static String getHostFromURL(String url)
      Returns the host part of the URL.
      Parameters:
      url - a URL
      Returns:
      just the host

    • getBaseURL

      public static String getBaseURL(String url)
      The basic URL without any parameters: >scheme<:>authority<.
      Parameters:
      url - a full URL
      Returns:
      the basic URL

    • getObjectURI

      public static String getObjectURI(ParaObject obj, boolean includeName, boolean includeId)
      Returns the default URL for a given domain object.
      Parameters:
      obj - the domain object
      includeName - true if we want to include the name of the object in the URL
      includeId - true if we want to include the ID of the object in the URL
      Returns:
      the object's URL - e.g. /users/123-name, /users/, /users/123

    • getSystemProperty

      public static String getSystemProperty(String name)
      Same as System.getProperty(java.lang.String).
      Parameters:
      name - the name of the property
      Returns:
      the property value

    • isJsonType

      public static boolean isJsonType(String contentType)
      Checks if a response is of type JSON.
      Parameters:
      contentType - the value of "Content-Type" header
      Returns:
      true if JSON

    • singularToPlural

      public static String singularToPlural(String singul)
      Quick and dirty singular to plural conversion.
      Parameters:
      singul - a word
      Returns:
      a guess of its plural form

    • isBasicType

      public static boolean isBasicType(Class<?> clazz)
      Checks if a class is primitive, String or a primitive wrapper.
      Parameters:
      clazz - a class
      Returns:
      true if primitive or wrapper

    • type

      public static String type(Class<? extends ParaObject> clazz)
      Returns the simple name of a class in lowercase (AKA the type).
      Parameters:
      clazz - a core class
      Returns:
      just the name in lowercase or an empty string if clazz is null

    • getAllDeclaredFields

      public static List<Field> getAllDeclaredFields(Class<? extends ParaObject> clazz)
      Returns a list of all declared fields in a class. Transient and serialVersionUID fields are skipped. This method scans parent classes as well.
      Parameters:
      clazz - a class to scan
      Returns:
      a list of fields including those of the parent classes excluding the Object class.

    • getNewId

      public static String getNewId()
      Distributed id generator. Relies on node/worker ids and datacenter ids to prevent collisions.
      Returns:
      a long unique ID string of digits