在文件的每一段下面插入一个空行？解决方法

在文件的每一段下面插入一个空行？
package aa.com;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;

public class InsertEnter {
public static void main(String[] args) {
getFile(new File("C:\\Users\\Administrator\\Desktop\\aa.txt"),new File("C:\\Users\\Administrator\\Desktop\\bb.txt"));
}
private static void getFile(File f,File fi) {
try {
FileInputStream in=new FileInputStream(f);
BufferedReader read=new BufferedReader(new InputStreamReader(in));
FileOutputStream out=new FileOutputStream(fi);
PrintWriter print=new PrintWriter(out);
String mm=null;
do{
mm=read.readLine();
if(null!=mm&&mm.length()>0){
System.out.println("oijoij");
print.println(mm);
print.println("\n");
}
}while(null!=mm);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
谁能帮我看一下，代码有什么问题，谢谢

[解决办法]
应该是文件没有关闭的原因吧

Java code

package aa.com;import java.io.BufferedReader;import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStreamReader;import java.io.PrintWriter;public class InsertEnter {    public static void main(String[] args) {        getFile(new File("aa.txt"),new File("bb.txt"));    }        private static void getFile(File f,File fi) {        try {            FileInputStream in=new FileInputStream(f);            BufferedReader read=new BufferedReader(new InputStreamReader(in));            FileOutputStream out=new FileOutputStream(fi);            PrintWriter print=new PrintWriter(out);            String mm=null;            do{                mm=read.readLine();                if(null!=mm&&mm.length()>0){                    System.out.println("oijoij");                    print.println(mm);                    print.println("\n");                }            } while(null!=mm);            print.close();//关闭文件流            out.close();        } catch (FileNotFoundException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }    }}