字符编码

查看支持哪些字符编码：

 

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package com.nio;

 

import java.nio.charset.Charset;

import java.util.Map;

import java.util.Set;

import java.util.SortedMap;

 

/**

 * 字符集：charset

 * 编码：字符串->字节数组

 * 解码：字节数组->字符串

 */

public class TestCharset {

    public static void main(String[] args) {

        //查看Charset支持的字符编码

        SortedMap<String, Charset> map = Charset.availableCharsets();

        Set<Map.Entry<String, Charset>> entries = map.entrySet();

        for (Map.Entry<String, Charset> entry : entries) {

            System.out.println(entry.getKey()+"="+entry.getValue());

        }

    }

}

 

　　

运行结果：

 

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Big5=Big5

Big5-HKSCS=Big5-HKSCS

CESU-8=CESU-8

EUC-JP=EUC-JP

EUC-KR=EUC-KR

GB18030=GB18030

GB2312=GB2312

GBK=GBK

IBM-Thai=IBM-Thai

IBM00858=IBM00858

IBM01140=IBM01140

IBM01141=IBM01141

IBM01142=IBM01142

IBM01143=IBM01143

IBM01144=IBM01144

IBM01145=IBM01145

IBM01146=IBM01146

IBM01147=IBM01147

IBM01148=IBM01148

IBM01149=IBM01149

IBM037=IBM037

IBM1026=IBM1026

IBM1047=IBM1047

IBM273=IBM273

IBM277=IBM277

IBM278=IBM278

IBM280=IBM280

IBM284=IBM284

IBM285=IBM285

IBM290=IBM290

IBM297=IBM297

IBM420=IBM420

IBM424=IBM424

IBM437=IBM437

IBM500=IBM500

IBM775=IBM775

IBM850=IBM850

IBM852=IBM852

IBM855=IBM855

IBM857=IBM857

IBM860=IBM860

IBM861=IBM861

IBM862=IBM862

IBM863=IBM863

IBM864=IBM864

IBM865=IBM865

IBM866=IBM866

IBM868=IBM868

IBM869=IBM869

IBM870=IBM870

IBM871=IBM871

IBM918=IBM918

ISO-2022-CN=ISO-2022-CN

ISO-2022-JP=ISO-2022-JP

ISO-2022-JP-2=ISO-2022-JP-2

ISO-2022-KR=ISO-2022-KR

ISO-8859-1=ISO-8859-1

ISO-8859-13=ISO-8859-13

ISO-8859-15=ISO-8859-15

ISO-8859-2=ISO-8859-2

ISO-8859-3=ISO-8859-3

ISO-8859-4=ISO-8859-4

ISO-8859-5=ISO-8859-5

ISO-8859-6=ISO-8859-6

ISO-8859-7=ISO-8859-7

ISO-8859-8=ISO-8859-8

ISO-8859-9=ISO-8859-9

JIS_X0201=JIS_X0201

JIS_X0212-1990=JIS_X0212-1990

KOI8-R=KOI8-R

KOI8-U=KOI8-U

Shift_JIS=Shift_JIS

TIS-620=TIS-620

US-ASCII=US-ASCII

UTF-16=UTF-16

UTF-16BE=UTF-16BE

UTF-16LE=UTF-16LE

UTF-32=UTF-32

UTF-32BE=UTF-32BE

UTF-32LE=UTF-32LE

UTF-8=UTF-8

windows-1250=windows-1250

windows-1251=windows-1251

windows-1252=windows-1252

windows-1253=windows-1253

windows-1254=windows-1254

windows-1255=windows-1255

windows-1256=windows-1256

windows-1257=windows-1257

windows-1258=windows-1258

windows-31j=windows-31j

x-Big5-HKSCS-2001=x-Big5-HKSCS-2001

x-Big5-Solaris=x-Big5-Solaris

x-euc-jp-linux=x-euc-jp-linux

x-EUC-TW=x-EUC-TW

x-eucJP-Open=x-eucJP-Open

x-IBM1006=x-IBM1006

x-IBM1025=x-IBM1025

x-IBM1046=x-IBM1046

x-IBM1097=x-IBM1097

x-IBM1098=x-IBM1098

x-IBM1112=x-IBM1112

x-IBM1122=x-IBM1122

x-IBM1123=x-IBM1123

x-IBM1124=x-IBM1124

x-IBM1166=x-IBM1166

x-IBM1364=x-IBM1364

x-IBM1381=x-IBM1381

x-IBM1383=x-IBM1383

x-IBM300=x-IBM300

x-IBM33722=x-IBM33722

x-IBM737=x-IBM737

x-IBM833=x-IBM833

x-IBM834=x-IBM834

x-IBM856=x-IBM856

x-IBM874=x-IBM874

x-IBM875=x-IBM875

x-IBM921=x-IBM921

x-IBM922=x-IBM922

x-IBM930=x-IBM930

x-IBM933=x-IBM933

x-IBM935=x-IBM935

x-IBM937=x-IBM937

x-IBM939=x-IBM939

x-IBM942=x-IBM942

x-IBM942C=x-IBM942C

x-IBM943=x-IBM943

x-IBM943C=x-IBM943C

x-IBM948=x-IBM948

x-IBM949=x-IBM949

x-IBM949C=x-IBM949C

x-IBM950=x-IBM950

x-IBM964=x-IBM964

x-IBM970=x-IBM970

x-ISCII91=x-ISCII91

x-ISO-2022-CN-CNS=x-ISO-2022-CN-CNS

x-ISO-2022-CN-GB=x-ISO-2022-CN-GB

x-iso-8859-11=x-iso-8859-11

x-JIS0208=x-JIS0208

x-JISAutoDetect=x-JISAutoDetect

x-Johab=x-Johab

x-MacArabic=x-MacArabic

x-MacCentralEurope=x-MacCentralEurope

x-MacCroatian=x-MacCroatian

x-MacCyrillic=x-MacCyrillic

x-MacDingbat=x-MacDingbat

x-MacGreek=x-MacGreek

x-MacHebrew=x-MacHebrew

x-MacIceland=x-MacIceland

x-MacRoman=x-MacRoman

x-MacRomania=x-MacRomania

x-MacSymbol=x-MacSymbol

x-MacThai=x-MacThai

x-MacTurkish=x-MacTurkish

x-MacUkraine=x-MacUkraine

x-MS932_0213=x-MS932_0213

x-MS950-HKSCS=x-MS950-HKSCS

x-MS950-HKSCS-XP=x-MS950-HKSCS-XP

x-mswin-936=x-mswin-936

x-PCK=x-PCK

x-SJIS_0213=x-SJIS_0213

x-UTF-16LE-BOM=x-UTF-16LE-BOM

X-UTF-32BE-BOM=X-UTF-32BE-BOM

X-UTF-32LE-BOM=X-UTF-32LE-BOM

x-windows-50220=x-windows-50220

x-windows-50221=x-windows-50221

x-windows-874=x-windows-874

x-windows-949=x-windows-949

x-windows-950=x-windows-950

x-windows-iso2022jp=x-windows-iso2022jp

 

　　

编码解码小案例：

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package com.nio;

 

import java.nio.ByteBuffer;

import java.nio.CharBuffer;

import java.nio.charset.CharacterCodingException;

import java.nio.charset.Charset;

import java.nio.charset.CharsetDecoder;

import java.nio.charset.CharsetEncoder;

 

/**

 * 字符集

 * 编码和解码的小案例

 */

public class TestCharsetDemo {

    public static void main(String[] args) throws CharacterCodingException {

        Charset cs1 = Charset.forName("GBK");

        //获取解码器

        CharsetEncoder ce = cs1.newEncoder();

        //获取解码器

        CharsetDecoder cd = cs1.newDecoder();

        CharBuffer cBuf = CharBuffer.allocate(1024);

        cBuf.put("张家口加油！");

        cBuf.flip();

 

        //编码

        ByteBuffer bBuf = ce.encode(cBuf);

        for (int i=0;i<12;i++) {

            System.out.println(bBuf.get());

        }

 

        //解码

        bBuf.flip();

        CharBuffer cBuf2 = cd.decode(bBuf);

        System.out.println(cBuf2.toString());

 

        //解码 使用utf-8进行解码

        Charset cs2 = Charset.forName("UTF-8");

        bBuf.flip();

        CharBuffer cBuf3 = cs2.decode(bBuf);

        System.out.println(cBuf3.toString());

 

    }

}

　　

运行结果：

 

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-43

-59

-68

-46

-65

-38

-68

-45

-45

-51

-93

-95

张家口加油！

�żҿڼ��ͣ�

 

　　

由此可见，当编码和解码的方式不同的时候，会出现乱码。这在实际项目开发过程中一定要注意。

 

当客户端向服务端发送一个读写请求的时候，服务端无法判断读写请求中信息真实有效的时候，就会陷入阻塞状态。