提高字符复制效率

package com.utils;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;

public class BufferedCopy {

public static void main(String[] args) {
// TODO 自动生成的方法存根
FileReader fileReader = null;
FileWriter fileWriter = null;
BufferedReader bufferedReader = null;
PrintWriter printWriter = null;

try {
fileReader=new FileReader("out.txt");
fileWriter=new FileWriter("d:/out.txt");
bufferedReader =new BufferedReader (fileReader);
printWriter =new PrintWriter(fileWriter);
String flag="";
while((flag=bufferedReader.readLine())!=null){
printWriter.println(flag);
}
} catch (FileNotFoundException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
} catch (IOException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}finally{
if(printWriter!=null){
printWriter.close();
}
if(bufferedReader!=null){
try {
bufferedReader.close();
} catch (IOException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
}
if(fileWriter!=null){
try {
fileWriter.close();
} catch (IOException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
}
if(fileReader!=null){
try {
fileReader.close();
} catch (IOException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
}
}

}

}