jdk太神奇了 (StandardCharsets 源码)

Posted 2021-06-15 辉常努腻

jdk太神奇了

• 我们不再需要自行定义字符集常量。 直接调用java.nio.charset包下的 StandardCharsets
  类，指定对应的字符集即可。

• 以前发现了apache的FileUtils包里面有几个这样的常量，还沾沾自喜，

• 现在才发现jdk已经为我们提供了这些字符编码的静态常量，不得不说jdk太神奇了

StandardCharsets 源码

package java.nio.charset;

/**
 * Constant definitions for the standard {@link Charset Charsets}. These
 * charsets are guaranteed to be available on every implementation of the Java
 * platform.
 *
 * @see <a href="Charset#standard">Standard Charsets</a>
 * @since 1.7
 */
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");
}

怎么使用

非常简单

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

这些自己更放心啦。