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Java FileReader class

FileReader class inherits from InputStreamReader class. This class reads the data stream by character. You can create objects needed through the following constructor.

Creates a new FileReader, given the File to read from. 

FileReader(File file)

Creates a new FileReader, given the data read from the FileDescriptor. 

FileReader(FileDescriptor fd)

Creates a new FileReader, given the data read from the file name. 

FileReader(String fileName)

After creating FIleReader objects, it can refer to the following list of file operation method.

No. File Description
1 public int read () throws IOException
Read a single character, return to the character read an int variable represents
2 public int read (char [] c , int offset, int len)
C reads characters into an array, returns the number of characters to read

Examples 

import java.io.*;
public class FileRead{
   public static void main(String args[])throws IOException{
      File file = new File("Hello1.txt");
      // 创建文件
      file.createNewFile();
      // creates a FileWriter Object
      FileWriter writer = new FileWriter(file); 
      // 向文件写入内容
      writer.write("This\n is\n an\n example\n"); 
      writer.flush();
      writer.close();
      // 创建 FileReader 对象
      FileReader fr = new FileReader(file); 
      char [] a = new char[50];
      fr.read(a); // 读取数组中的内容
      for(char c : a)
          System.out.print(c); // 一个一个打印字符
      fr.close();
   }
}

The above examples compiled results are as follows: 

This
is
an
example