How to copy text files in Java I summed up 14 kinds (by character read 4, read by byte 8 kinds!?? )

How to copy files in Java

If you read by character, there can be 4 kinds, basic 2 kinds, efficient 2 kinds, efficient special 1 kinds

The No. 0 Type:

public class Copyfiledemo {public static void main (string[] args) throws exception{//packaging data source BufferedReader reader = new Buff Eredreader (New FileReader ("A.txt"));//package destination BufferedWriter writer = new BufferedWriter (New FileWriter ("B.txt"));// Read and write data string line = Null;while ((Line=reader.readline ())!=null) {writer.write (lines); Writer.newline ();//Add New row, Otherwise, the contents of the file will not be wrapped Writer.flush ();} Release resources Writer.close (); Writer.close ();}}

First: Join buffer buffered read one character array at a time

public class Copyfiletest {public static void main (string[] args) throws exception{//encapsulated data source BufferedReader reader = new Buff Eredreader (New FileReader ("A.txt"));//package destination BufferedWriter writer = new BufferedWriter (New FileWriter ("B.txt"));// One of two ways to read one character array at a time char[] chs = new Char[1024];int Len=0;while ((Len=reader.read (CHS))!=-1) {writer.write (Chs,0,len); Writer.flush ();//Remember to refresh}//release Resources writer.close (); Reader.close ();}}

Second: Add buffer buffered read one character at a time

public class Copyfiletest {public static void main (string[] args) throws exception{//encapsulated data source BufferedReader reader = new Buff Eredreader (New FileReader ("A.txt"));//package destination BufferedWriter writer = new BufferedWriter (New FileWriter ("B.txt"));// Reads one character at a time, int ch=0;while ((Ch=reader.read ())!=-1) {writer.write (ch);} Release resources Writer.close (); Reader.close ();}}

The third type: normal one-time reading of a character array

public class Bufferedcopyfiletest {public static void main (string[] args) throws exception{//encapsulated data source FileReader reader = new FileReader ("A.txt");//package destination FileWriter writer = new FileWriter ("B.txt");//read one character array at a time char[] chs = new Char[1024];int len= 0;while (Len=reader.read (CHS))!=-1) {writer.write (Chs,0,len); Writer.flush ();} Writer.close (); Reader.close ();}}

Third: Normal read one character at a time

public class Bufferedcopyfiletest {public static void main (string[] args) throws exception{//encapsulated data source FileReader reader = new FileReader ("A.txt");//package destination FileWriter writer = new FileWriter ("B.txt");//read one character at a time int ch=0;while ((Ch=reader.read ())! =-1) {writer.write (ch);} Writer.close (); Reader.close ();}}

If you read in bytes, you can have 8

First: Convert the byte stream to a character stream to read one of the characters at a time

public class Copy {public static void main (string[] args) throws Exception {//Encapsulated data source (converts a byte stream to a character stream) InputStreamReader ISR = new InputStreamReader (New FileInputStream ("A.txt"));//Package destination (convert byte stream to character stream) OutputStreamWriter OSW = new OutputStreamWriter ( New FileOutputStream ("B.txt"));//read one character at a time int ch=0;while ((Ch=isr.read ())!=-1) {osw.write (ch);} Close resource Osw.close (); Isr.close ();}}

Second: Convert a byte stream to a character stream to read an array of characters at a time

public class Copy {public static void main (string[] args) throws Exception {//Encapsulated data source (converts a byte stream to a character stream) InputStreamReader ISR = new InputStreamReader (New FileInputStream ("A.txt"));//Package destination (convert byte stream to character stream) OutputStreamWriter OSW = new OutputStreamWriter ( New FileOutputStream ("B.txt"));//read one character array at a time char[] chs = new Char[1024];int Len=0;while ((Len=isr.read (CHS))!=-1) { Osw.write (Chs,0,len); Osw.flush ();} Close resource Osw.close (); Isr.close ();}}

The third type: efficient byte stream reads and writes an array of bytes at a time:

public static void Method4 (String srcstring, String deststring)                  throws IOException {              Bufferedinputstream bis = NE W Bufferedinputstream (New FileInputStream (                      srcstring));              Bufferedoutputstream BOS = new Bufferedoutputstream (                      new FileOutputStream (deststring));                    byte[] bys = new byte[1024];              int len = 0;              while (len = Bis.read (bys))! =-1) {                  bos.write (bys, 0, Len);              }                    Bos.close ();              Bis.close ();          }  

Fourth: Efficient byte stream reads one character at a time:

public static void Method3 (String srcstring, String deststring)                  throws IOException {              Bufferedinputstream bis = NE W Bufferedinputstream (New FileInputStream (                      srcstring));              Bufferedoutputstream BOS = new Bufferedoutputstream (                      new FileOutputStream (deststring));                    int by = 0;              while (by = Bis.read ())! =-1) {                  bos.write (by);                    }                    Bos.close ();              Bis.close ();          }  

Fifth: Ordinary byte-stream objects read one array of bytes at a time

public static void Method2 (String srcstring, String deststring)                  throws IOException {              FileInputStream fis = new Fil Einputstream (srcstring);              FileOutputStream fos = new FileOutputStream (deststring);                    byte[] bys = new byte[1024];              int len = 0;              while (len = Fis.read (bys))! =-1) {                  fos.write (bys, 0, Len);              }                    Fos.close ();              Fis.close ();          }        

Sixth type: Normal byte stream object reads one bytes at a time

public static void Method1 (String srcstring, String deststring)                  throws IOException {              FileInputStream fis = new Fil Einputstream (srcstring);              FileOutputStream fos = new FileOutputStream (deststring);                    int by = 0;              while (by = Fis.read ())! =-1) {                  fos.write (by);              }                    Fos.close ();              Fis.close ();          }  

The seventh type:BufferedReader reader = new BufferedReader (new InputStreamReader (New FileInputStream ("A.txt"));
BufferedWriter writer = new BufferedWriter (new OutputStreamWriter (New FileOutputStream ("B,txt")), then one character at a time

Eighth:BufferedReader reader = new BufferedReader (new InputStreamReader (New FileInputStream ("A.txt"));
BufferedWriter writer = new BufferedWriter (new OutputStreamWriter (New FileOutputStream ("B,txt")), and one character array at a time

Note that copying pictures, video, audio, only 4 ways (byte stream reading), cannot be read with a character stream

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How to copy text files in Java I summed up 14 kinds (by character read 4, read by byte 8 kinds!?? )