CreatFile
1 package filetest; 2 import java.io.*; 3 import java.util.*; 4 public class CreatFile { 5 6 public CreatFile(){ 7 File file = new File("E:\eclipse\filetest"+File.separator+"hello.txt"); 8 try { 9 file.createNewFile(); 10 } catch (IOException e) { 11 // TODO Auto-generated catch block 12 e.printStackTrace(); 13 } 14 Scanner fin; 15 try { 16 fin = new Scanner(file); 17 while(fin.hasNext()){ 18 String s = fin.next(); 19 System.out.println(s); 20 21 } 22 } catch (FileNotFoundException e) { 23 // TODO Auto-generated catch block 24 e.printStackTrace(); 25 } 26 27 } 28 public static void main(String[] args) throws IOException { 29 // CreatFile f = new CreatFile(); 30 File file = new File("E:\eclipse\filetest"+File.separator+"hello.txt"); 31 file.createNewFile(); 32 Scanner fin = new Scanner(file); 33 while(fin.hasNext()){ 34 String s = fin.next(); 35 System.out.println(s); 36 37 } 38 39 } 40 41 }
InputStream
1 package filetest; 2 3 import java.io.*; 4 5 6 public class InPutStream { 7 8 public static void main(String[] args) throws IOException { 9 int len; 10 byte[] buffer = new byte[100]; 11 File file = new File("E:\eclipse\filetest"+File.separator+"hello_1.txt"); 12 FileInputStream fin = new FileInputStream(file); 13 while((len=fin.read(buffer))>0){ 14 String s = new String(buffer,0,len); 15 System.out.println(s); 16 17 } 18 } 19 20 }
OutputStream
1 package filetest; 2 import java.io.*; 3 public class OutPutStream { 4 5 public static void main(String[] args) throws IOException { 6 byte[] buffer = "get string!".getBytes(); 7 String filename = "E:\eclipse\filetest"+File.separator+"hello_1.txt"; 8 FileOutputStream fout = new FileOutputStream(filename); 9 10 fout.write(buffer); 11 12 //System.out.println(); 13 } 14 15 }
ReaderWriter
1 package filetest; 2 import java.io.*; 3 4 public class ReaderWriter { 5 6 public static void main(String[] args) throws IOException { 7 //读入字符数据 8 char s[] = new char [10]; 9 File file = new File("E:\eclipse\filetest"+File.separator+"hello.txt"); 10 FileReader fin = new FileReader(file); 11 fin.read(s); 12 System.out.println(s); 13 fin.close(); 14 //输出字符数据 15 char []c ={'j','a','v','a'}; 16 //File file = new File("E:\eclipse\filetest"+File.separator+"hello.txt"); 17 FileWriter fout = new FileWriter(file); 18 fout.write(c); 19 System.out.println(c); 20 fout.close(); 21 } 22 23 }