Package org.apache.commons.io

Class Charsets

  • public class Charsets
extends java.lang.Object
    Charsets required of every implementation of the Java platform. From the Java documentation Standard charsets:

    Every implementation of the Java platform is required to support the following character encodings. Consult the release documentation for your implementation to see if any other encodings are supported. Consult the release documentation for your implementation to see if any other encodings are supported.

    • US-ASCII
      Seven-bit ASCII, a.k.a. ISO646-US, a.k.a. the Basic Latin block of the Unicode character set.
    • ISO-8859-1
      ISO Latin Alphabet No. 1, a.k.a. ISO-LATIN-1.
    • UTF-8
      Eight-bit Unicode Transformation Format.
    • UTF-16BE
      Sixteen-bit Unicode Transformation Format, big-endian byte order.
    • UTF-16LE
      Sixteen-bit Unicode Transformation Format, little-endian byte order.
    • UTF-16
      Sixteen-bit Unicode Transformation Format, byte order specified by a mandatory initial byte-order mark (either order accepted on input, big-endian used on output.)
    Since:
    2.3
    See Also:
    Standard charsets

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static java.nio.charset.Charset ISO_8859_1
      Deprecated.
      Use Java 7's StandardCharsets
      static java.nio.charset.Charset US_ASCII
      Deprecated.
      Use Java 7's StandardCharsets
      static java.nio.charset.Charset UTF_16
      Deprecated.
      Use Java 7's StandardCharsets
      static java.nio.charset.Charset UTF_16BE
      Deprecated.
      Use Java 7's StandardCharsets
      static java.nio.charset.Charset UTF_16LE
      Deprecated.
      Use Java 7's StandardCharsets
      static java.nio.charset.Charset UTF_8
      Deprecated.
      Use Java 7's StandardCharsets

    • Constructor Summary

      Constructors 
      Constructor Description
      Charsets()
      Deprecated.
      Will be private in 4.0

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static boolean isAlias​(java.nio.charset.Charset charset, java.lang.String charsetName)
      Tests whether the given non-null Charset has an alias of the given name.
      static boolean isUTF8​(java.nio.charset.Charset charset)
      Tests whether a given encoding is UTF-8.
      static java.util.SortedMap<java.lang.String,​java.nio.charset.Charset> requiredCharsets()
      Constructs a sorted map from canonical charset names to charset objects required of every implementation of the Java platform.
      static java.nio.charset.Charset toCharset​(java.lang.String charsetName)
      Returns a Charset for the named charset.
      static java.nio.charset.Charset toCharset​(java.lang.String charsetName, java.nio.charset.Charset defaultCharset)
      Returns a Charset for the named charset.
      static java.nio.charset.Charset toCharset​(java.nio.charset.Charset charset)
      Returns the given Charset or the default Charset if the given Charset is null.
      static java.nio.charset.Charset toCharset​(java.nio.charset.Charset charset, java.nio.charset.Charset defaultCharset)
      Returns the given charset if non-null, otherwise return defaultCharset.
      static java.nio.charset.Charset toCharsetDefault​(java.lang.String charsetName, java.nio.charset.Charset defaultCharset)
      Returns a Charset for the named charset or the defaultCharset.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • ISO_8859_1

        @Deprecated
public static final java.nio.charset.Charset ISO_8859_1
        Deprecated.
        Use Java 7's StandardCharsets
        CharEncodingISO Latin Alphabet No. 1, a.k.a. ISO-LATIN-1.

        Every implementation of the Java platform is required to support this character encoding.

        See Also:
        Standard charsets

      • US_ASCII

        @Deprecated
public static final java.nio.charset.Charset US_ASCII
        Deprecated.
        Use Java 7's StandardCharsets

        Seven-bit ASCII, also known as ISO646-US, also known as the Basic Latin block of the Unicode character set.

        Every implementation of the Java platform is required to support this character encoding.

        See Also:
        Standard charsets

      • UTF_16

        @Deprecated
public static final java.nio.charset.Charset UTF_16
        Deprecated.
        Use Java 7's StandardCharsets

        Sixteen-bit Unicode Transformation Format, The byte order specified by a mandatory initial byte-order mark (either order accepted on input, big-endian used on output)

        Every implementation of the Java platform is required to support this character encoding.

        See Also:
        Standard charsets

      • UTF_16BE

        @Deprecated
public static final java.nio.charset.Charset UTF_16BE
        Deprecated.
        Use Java 7's StandardCharsets

        Sixteen-bit Unicode Transformation Format, big-endian byte order.

        Every implementation of the Java platform is required to support this character encoding.

        See Also:
        Standard charsets

      • UTF_16LE

        @Deprecated
public static final java.nio.charset.Charset UTF_16LE
        Deprecated.
        Use Java 7's StandardCharsets

        Sixteen-bit Unicode Transformation Format, little-endian byte order.

        Every implementation of the Java platform is required to support this character encoding.

        See Also:
        Standard charsets

      • UTF_8

        @Deprecated
public static final java.nio.charset.Charset UTF_8
        Deprecated.
        Use Java 7's StandardCharsets

        Eight-bit Unicode Transformation Format.

        Every implementation of the Java platform is required to support this character encoding.

        See Also:
        Standard charsets

    • Constructor Detail

      • Charsets

        @Deprecated
public Charsets()
        Deprecated.
        Will be private in 4.0
        Construct a new instance.

    • Method Detail

      • isAlias

        public static boolean isAlias​(java.nio.charset.Charset charset,
                              java.lang.String charsetName)
        Tests whether the given non-null Charset has an alias of the given name.
        Parameters:
        charset - a non-null Charset.
        charsetName - The name to test.
        Returns:
        whether the given non-null charset name is a UTF-8 alias.
        Since:
        2.20.0

      • isUTF8

        public static boolean isUTF8​(java.nio.charset.Charset charset)
        Tests whether a given encoding is UTF-8. If the given charset is null, then check the platform's default encoding.
        Parameters:
        charset - If the given charset is null, then check the platform's default encoding.
        Returns:
        whether a given encoding is UTF-8.
        Since:
        2.20.0

      • requiredCharsets

        public static java.util.SortedMap<java.lang.String,​java.nio.charset.Charset> requiredCharsets()
        Constructs a sorted map from canonical charset names to charset objects required of every implementation of the Java platform.

        From the Java documentation Standard charsets:

        Returns:
        An immutable, case-insensitive map from canonical charset names to charset objects.
        Since:
        2.5
        See Also:
        Charset.availableCharsets()

      • toCharset

        public static java.nio.charset.Charset toCharset​(java.nio.charset.Charset charset)
        Returns the given Charset or the default Charset if the given Charset is null.
        Parameters:
        charset - A charset or null.
        Returns:
        the given Charset or the default Charset if the given Charset is null
        See Also:
        Charset.defaultCharset()

      • toCharset

        public static java.nio.charset.Charset toCharset​(java.nio.charset.Charset charset,
                                                 java.nio.charset.Charset defaultCharset)
        Returns the given charset if non-null, otherwise return defaultCharset.
        Parameters:
        charset - The charset to test, may be null.
        defaultCharset - The charset to return if charset is null, may be null.
        Returns:
        a Charset.
        Since:
        2.12.0

      • toCharset

        public static java.nio.charset.Charset toCharset​(java.lang.String charsetName)
                                          throws java.nio.charset.UnsupportedCharsetException
        Returns a Charset for the named charset. If the name is null, return the default Charset.
        Parameters:
        charsetName - The name of the requested charset, may be null.
        Returns:
        a Charset for the named charset.
        Throws:
        java.nio.charset.UnsupportedCharsetException - If the named charset is unavailable (unchecked exception).
        See Also:
        Charset.defaultCharset()

      • toCharset

        public static java.nio.charset.Charset toCharset​(java.lang.String charsetName,
                                                 java.nio.charset.Charset defaultCharset)
                                          throws java.nio.charset.UnsupportedCharsetException
        Returns a Charset for the named charset. If the name is null, return the given default Charset.
        Parameters:
        charsetName - The name of the requested charset, may be null.
        defaultCharset - The charset to return if charsetName is null, may be null.
        Returns:
        a Charset for the named charset.
        Throws:
        java.nio.charset.UnsupportedCharsetException - If the named charset is unavailable (unchecked exception).
        Since:
        2.12.0

      • toCharsetDefault

        public static java.nio.charset.Charset toCharsetDefault​(java.lang.String charsetName,
                                                        java.nio.charset.Charset defaultCharset)
        Returns a Charset for the named charset or the defaultCharset.

        If charsetName cannot load a charset, return defaultCharset. Therefore, this method should never fail and always return a Charset.

        Parameters:
        charsetName - The name of the requested charset, may be null.
        defaultCharset - The charset to return if charsetName is null or there is a problem, may be null which returns Charset.defaultCharset().
        Returns:
        a Charset for the named charset or defaultCharset if any errors occur.
        Since:
        2.20.0
        See Also:
        Charset.defaultCharset()