java 文件字符输入、输出流

import java.io.*;
public class Example10_6 {
public static void main(String args[]) {
File sourceFile = new File("a.txt");  //读取的文件
File targetFile = new File("b.txt");  //写入的文件
char c[] =new char[19];               //char型数组
try{
Writer out = new FileWriter(targetFile,true); //指向目的地的输出流
Reader in  = new FileReader(sourceFile);   //指向源的输入流
int n = -1;
while((n=in.read(c))!=-1) {
out.write(c,0,n);
}
out.flush();
out.close();
}
catch(IOException e) {
System.out.println("Error "+e);
}
}
}