StandardCharsets jdk自带的字符编码常量字段

用StandardCharsets.UTF_8 返回”UTF-8″这个字符

public final class StandardCharsets {

    private StandardCharsets() {
        throw new AssertionError("No java.nio.charset.StandardCharsets instances for you!");
    }
    /**
     * Seven-bit ASCII, a.k.a. ISO646-US, a.k.a. the Basic Latin block of the
     * Unicode character set
     */
    public static final Charset US_ASCII = Charset.forName("US-ASCII");
    /**
     * ISO Latin Alphabet No. 1, a.k.a. ISO-LATIN-1
     */
    public static final Charset ISO_8859_1 = Charset.forName("ISO-8859-1");
    /**
     * Eight-bit UCS Transformation Format
     */
    public static final Charset UTF_8 = Charset.forName("UTF-8");
    /**
     * Sixteen-bit UCS Transformation Format, big-endian byte order
     */
    public static final Charset UTF_16BE = Charset.forName("UTF-16BE");
    /**
     * Sixteen-bit UCS Transformation Format, little-endian byte order
     */
    public static final Charset UTF_16LE = Charset.forName("UTF-16LE");
    /**
     * Sixteen-bit UCS Transformation Format, byte order identified by an
     * optional byte-order mark
     */
    public static final Charset UTF_16 = Charset.forName("UTF-16"); 
}

直接用

@Test
    public void testUTF8() {
        System.out.println(StandardCharsets.UTF_8.name()); //UTF-8
    }