字符流是以字符（两个字节）为单位的流，Reader和Writer代表字符输入流和字符输出流，它们专为Java频繁的文字IO操作而设计的。常用方法列举如下：
int read();从流中读取一个字符
int reader(char[] buffer);读取若干可读字符至缓冲区，返回实际读取的字符个 数
writer(int);将int型作为char类型字符输出到目标流中
writer(String);将字符串输出到目标流中。
writer(char[] buffer,int offset,int len);将字符缓冲区的字符从offset位置起共len个字符输出到目标流中
示例1代码：
public class TestWriter{
public static void main(String[] args) {
Writer writer = null;
try {
writer = new FileWriter("rw.txt");
writer.write('中');
writer.write("文汉字");
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (writer != null) {
try {
writer.flush();
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
示例2代码：
public class TestReader{
public static void main(String[] args) {
Reader reader = null;
try {
reader = new FileReader("rw.txt");
int ch=-1;
while((ch=reader.read())!=-1){
System.out.print((char)ch);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
