Java I/O操作

按字节读取读取文件，并且将文件里面的内容写到另外一个文件里面去

public class CopyBytes {
    public static void main(String[] args) throws IOException {
        FileInputStream in = null;
        FileOutputStream out = null;
        try {
            in = new FileInputStream("xanadu.txt");
            out = new FileOutputStream("outagain.txt");
            int c;  

            while ((c = in.read()) != -1) {
                out.write(c);
            }  

        } finally {
            if (in != null) {
                in.close();
            }
            if (out != null) {
                out.close();
            }
        }
    }
}  

------------------------------------------------------------------------

缓冲存储

public class CopyCharacters {
    public static void main(String[] args) throws IOException {
        FileReader inputStream = null;
        FileWriter outputStream = null;  

        try {
            inputStream = new FileReader("xanadu.txt");
            outputStream = new FileWriter("characteroutput.txt");  

            int c;
            while ((c = inputStream.read()) != -1) {
                outputStream.write(c);
            }
        } finally {
            if (inputStream != null) {
                inputStream.close();
            }
            if (outputStream != null) {
                outputStream.close();
            }
        }
    }
} 

------------------------------------------------------------------------------------

按行读取

public class CopyLines {
    public static void main(String[] args) throws IOException {
        BufferedReader inputStream = null;
        PrintWriter outputStream = null;  

        try {
            inputStream =
                new BufferedReader(new FileReader("xanadu.txt"));
            outputStream =
                new PrintWriter(new FileWriter("characteroutput.txt"));  

            String l;
            while ((l = inputStream.readLine()) != null) {
                outputStream.println(l);
            }
        } finally {
            if (inputStream != null) {
                inputStream.close();
            }
            if (outputStream != null) {
                outputStream.close();
            }
        }
    }
}  

----------------------------------------------------------------------------

直接读取文件内容

public class ScanXan {
    public static void main(String[] args) throws FileNotFoundException {
        Scanner s = null;
        try {
            s = new Scanner(new BufferedReader(new FileReader("xanadu.txt")));     

            while (s.hasNext()) {
                System.out.println(s.next());
            }
        } finally {
            if (s != null) {
                s.close();
            }
        }
    }
}  

本文出自 “阿凡达” 博客，请务必保留此出处http://shamrock.blog.51cto.com/2079212/751843