黑马程序员 java IO BufferedReader BufferdWriter 读文件 写文件

public class I_05_IO_MyBufferedReader {

/**
* @param args
*/
static FileReader fr;

public I_05_IO_MyBufferedReader(FileReader fr) {
this.fr = fr;
}

public static String myReadLine() throws IOException {
StringBuilder sb = new StringBuilder();
int flag = -1;
while ((flag = fr.read()) != -1) {
if ((char) flag == '\r')
continue;
if ((char) flag == '\n')
return sb.toString();
if (sb.length() != 0)
sb.toString();
sb.append((char) flag);
}
return null;
}

public static void myClose() throws IOException {
if (fr != null)
fr.close();
}

public static void main(String[] args) {
FileReader fr = null;
I_05_IO_MyBufferedReader myBr = null;
try {
String str;
fr = new FileReader(I_04_IO.path + I_04_IO.fileName);
myBr = new I_05_IO_MyBufferedReader(fr);
while ((str = myBr.myReadLine()) != null) {
System.out.println(str);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
myBr.myClose();
} catch (IOException e) {
e.printStackTrace();
}
}
}

}