转换流
一,转换流的使用
1.转换流:属于字符流
InputStreamReader:将一个字节的输入流转换为字符的输入流
OutputStreamWriter:将一个字符的输出流转换为字节的输出流
2.作用:提供字节流与字符流之间的转换
3.解码:字节、字节数组 --->字符数组、字符串
编码:字符数组、字符串 ---> 字节、字节数组
二,InputStreamReader的使用,实现字节的输入流到字符的输入流的转换
//时处理异常的话,仍然应该使用try-catch-finally
@Test
public void test1() throws IOException {
FileInputStream fis = new FileInputStream("dbcp.txt");//字节流
// InputStreamReader isr = new InputStreamReader(fis);//使用系统默认的字符集
//参数2 指明了字符集,具体使用哪个字符集,取决于文件dbcp.txt保存的字符集
InputStreamReader isr = new InputStreamReader(fis,"UTF-8");//使用系统默认的字符集
char[] cbuf = new char[20];
int len;
while ((len = isr.read(cbuf)) != -1){
String str = new String(cbuf,0,len);
System.out.print(str);
}
isr.close();
}
三,综合使用InputStreamReader和OutputStreamWriter
//时处理异常的话,仍然应该使用try-catch-finally
@Test
public void test2(){
InputStreamReader isr = null;
OutputStreamWriter osw = null;
try {
FileInputStream fis = new FileInputStream(new File("dbcp.txt"));
FileOutputStream fos = new FileOutputStream(new File("dbcpGBK.txt"));
isr = new InputStreamReader(fis,"UTF-8");
osw = new OutputStreamWriter(fos,"GBK");
//读写过程
char[] cbuf = new char[20];
int len ;
while ((len = isr.read(cbuf)) != -1){
osw.write(cbuf,0,len);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (osw!=null){
try {
osw.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (isr!=null){
try {
isr.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
标签:转换,字节,isr,len,new,InputStreamReader,cbuf
From: https://www.cnblogs.com/blwx/p/16717105.html