Java基础之读文件——使用输入流读取二进制文件（StreamInputFromFile）

控制台程序，读取Java基础之读文件部分（StreamOutputToFile）写入的50个fibonacci数字。
 1 import java.nio.file.*;
 2 import java.nio.*;
 3 import java.io.*;
 4 
 5 public class StreamInputFromFile {
 6   public static void main(String[] args) {
 7 
 8     Path file = Paths.get(System.getProperty("user.home")).resolve("Beginning Java Struff").resolve("fibonnaci.bin");
 9 
10     if(!Files.exists(file)) {
11       System.out.println(file + " does not exist. Terminating program.");
12       System.exit(1);
13     }
14 
15     final int count = 6;                                               // Number of values to be read each time
16 
17     // Buffer to hold count values
18     ByteBuffer buf = ByteBuffer.allocate(8*count);
19 
20     LongBuffer values = buf.asLongBuffer();
21     byte[] bytes = buf.array();                                        // Backing array for buf
22     int totalRead = 0;                                                 // Total value read
23     try(BufferedInputStream fileIn = new BufferedInputStream(Files.newInputStream(file))){
24       int numberRead = 0;
25       while(true) {
26         numberRead = fileIn.read(bytes, 0, bytes.length);
27         if(numberRead == -1)                                           // EOF reached
28           break;
29         totalRead += numberRead/8;                                     // Increment total
30 
31         for(int i = 0 ; i < numberRead/8 ; ++i)                        // Access as many as there are
32           System.out.format("%12d", values.get());
33 
34         System.out.println();                                          // New line
35         values.flip();                                                 // Reset for next input
36       }
37     System.out.format("%d  values read.%n", totalRead);
38     } catch(IOException e) {
39       System.err.println("Error writing file: " + file);
40       e.printStackTrace();
41     }
42   }
43 }