大神帮小弟我看看这段代码有什么有关问题吧_J2SE

大神帮我看看这段代码有什么问题吧
import java.io.*;
public class InputOut{
public static void main(String args[]){
int a =0;
FileInputStream in = null;
FileInputStream out = null;
in = new FileInputStream("F:/hljk/HelloWorld.java");
out = new FileOutputStream("D:/java/HW.java");
try {
while((a = in.read())!=-1){
out.write(a);
}
in.close();
out.close();
}
catch(FileNotFoundException e1){
System.out.println("此文件不存在");System.exit(-1);
}
catch(IOException e2){
System.out.println("复制失败");System.exit(-1);
}
System.out.println("复制成功");
}
}

------解决方案--------------------

Java code

public static void main(String[] args) {        int a = 0;        FileInputStream in = null;        FileOutputStream out = null;        try {            in = new FileInputStream("F:/hljk/HelloWorld.java");            out = new FileOutputStream("D:/java/HW.java");            while ((a = in.read()) != -1) {                out.write(a);            }        } catch (FileNotFoundException e1) {            System.out.println("此文件不存在");            System.exit(-1);        } catch (IOException e2) {            System.out.println("复制失败");            System.exit(-1);        } finally {            try {                if (in != null) {                    in.close();                }                if (out != null) {                    out.close();                }            } catch (IOException e) {                e.printStackTrace();            }        }        System.out.println("复制成功");    }
------解决方案--------------------
多看看别人写的代码，多领会一下，然后自己写代码的时候注意一下，就能解决好多问题
------解决方案--------------------
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