字符流

字节流操作中文数据不是特别的方便，所以就出现了转换流。转换流的作用就是把字节流转换字符流来使用。

转换流其实是一个字符流

字符流 = 字节流 + 编码表

编码表

A:就是由字符和对应的数值组成的一张表

B:常见的编码表 ASCII

ISO-8859-1 GB2312 GBK GB18030 UTF-8

C:字符串中的编码问题编码

String -- byte[]

解码

byte[] -- String

IO 流中的编码问题

A:OutputStreamWriter

OutputStreamWriter(OutputStream os): 默 认 编 码 ， GBK OutputStreamWriter(OutputStream os,String charsetName): 指定编码。

B:InputStreamReader

InputStreamReader(InputStream is): 默 认 编 码 ， GBK InputStreamReader(InputStream is,String charsetName): 指定编码

C:编码问题其实很简单编码只要一致即可

字符流

Reader

    |--InputStreamReader

    |--FileReader

    |--BufferedReader

Writer

    |--OutputStreamWriter

    |--FileWriter

    |--BufferedWriter

案例：复制文本文件 (5 种方式 )

//	基本字符流一次读写一个字符privatestaticvoid method1(String srcString, String destString) throws IOException {FileReader fr =	newFileReader(srcString);FileWriter fw =	newFileWriter(destString);int	ch = 0;while	((ch = fr.read()) != -1) { fw.write(ch);}fw.close();fr.close();}

//	基本字符流一次读写一个字符数组privatestaticvoid method2(String srcString, String destString) throws	IOException {FileReader fr =	newFileReader(srcString); FileWriter fw =	newFileWriter(destString);char  [] chs =	newchar [1024]; int	len = 0;while	((len = fr.read(chs)) != -1) { fw.write(chs, 0, len);}fw.close();fr.close();}

//	字符缓冲流一次读写一个字符privatestaticvoid method3(String srcString, String destString) throws	IOException {BufferedReader br = newBufferedReader(newFileReader(srcString));BufferedWriter bw = newBufferedWriter(newFileWriter(destString));int	ch = 0;while	((ch = br.read()) != -1) { bw.write(ch);}bw.close();br.close();}

//	字符缓冲流一次读写一个字符数组privatestaticvoid method4(String srcString, String destString) throws	IOException {BufferedReader br = newFileReader(srcString));newBufferedReader(newFileWriter(destString));char [] chs = newchar [1024];int	len = 0;while	((len = br.read(chs)) != -1) {bw.write(chs, 0, len);}bw.close();br.close();}

//	字符缓冲流一次读写一个字符串privatestaticvoid method5(String srcString, String destString) throws	IOException {BufferedReader br = newFileReader(srcString));newBufferedReader(newFileWriter(destString));String line = null;while	((line = br.readLine()) !=	null) { bw.write(line);bw.newLine();bw.flush();}