Java io

次日清晨醒着眼睛 / 2023-05-08 / 原文

创建文件的三种方式：

//        File file = new File("D:\\", "aaa.txt");
//        File file = new File("D:\\bbb.txt");
//        File file = new File(new File("D:\\"), "ccc.txt");

public class Main {
    public static void main(String[] args) throws IOException {


        File file = new File(new File("D:\\"), "ccc.txt");

        try (InputStream fileInputStream = new FileInputStream(file)) {
            int read;
            while((read=fileInputStream.read())!=-1){
                System.out.print((char)read);
            }
        }catch (IOException e){
            System.out.println(e.getMessage());
        }
        
        try (InputStream fileInputStream = new FileInputStream(file)) {
            byte[] buff=new byte[8];
            int len;
            while((len=fileInputStream.read(buff))!=-1){
                System.out.print(new String(buff,0,len));
            }
        }catch (IOException e){
            System.out.println(e.getMessage());
        }
    }
}

String sourceFile = "D:\\ccc.txt";
        String targetFile = "D:\\ddd.txt";
        FileInputStream fileInputStream = null;
        FileOutputStream fileOutputStream = null;

        try {
            fileInputStream = new FileInputStream(sourceFile);
            fileOutputStream = new FileOutputStream(targetFile);
            byte[] buff = new byte[1024];
            int readLine = 0;
            while ((readLine = fileInputStream.read(buff)) != -1) {
                fileOutputStream.write(buff, 0, readLine);
            }
        } catch (IOException e) {
            System.out.println(e.getMessage());
        } finally {
            if (fileInputStream != null) {
                fileInputStream.close();
            }
            if (fileOutputStream != null) {
                fileOutputStream.close();
            }
        }

try (FileReader reader = new FileReader("D:\\ccc.txt")) {
            char[] context=new char[1024];
            int len=0;
            while((len= reader.read(context))!=-1){
                System.out.println(new String(context,0,len));
            }
        } catch (IOException e) {
            throw new RuntimeException(e);
        }