Java FileInputStream和FileOutputSrteam

╰半橙微兮° 2024-04-01 14:31 76阅读 0赞

用法和原理和上一篇的FileReader、FileWriter差不多，就不细说。

直接给一个示例代码，将一个文件里的图片复制到另一个文件。

package IOStream;
    
    import org.junit.Test;
    
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.FileOutputStream;
    import java.io.IOException;
    
    public class demo3 {
        public static void main(String[] args) {
    
        }
        @Test
        public void Fileinoutstream(){
            FileInputStream fi=null;
            FileOutputStream fo=null;
            try {
                File f1=new File("D:\\Java develop\\Program\\superior_Java\\ingram.jpg");
                File f2=new File("D:\\Java develop\\Program\\superior_Java\\ingram2.jpg");
                fi=new FileInputStream(f1);
                fo=new FileOutputStream(f2);
                byte []arr=new byte[5];
                int len;
                while ((len=fi.read(arr))!=-1){
                    fo.write(arr,0,len);
                }
            } catch (IOException e) {
                throw new RuntimeException(e);
            } finally {
                try {if(fi!=null)
                    fi.close();
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
                try {if(fo!=null)
                    fo.close();
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
    
        }
    
    }

结果![d57622eace324148a12a8392b82376d8.png][]![d47dd097c5fa46c7ad16e99721f0ffaa.png][]

[d57622eace324148a12a8392b82376d8.png]: https://img-blog.csdnimg.cn/d57622eace324148a12a8392b82376d8.png
[d47dd097c5fa46c7ad16e99721f0ffaa.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/01/f0bdd2f4e115486e8711b3e3b9da82c0.png