java.io.FilterInputStream.read(byte[] b)方法實例
java.io.FilterInputStream.read(byte[] b) 方法從這個濾波器的輸入流中讀取b.length一個字節數據到數組。此方法阻塞,直到輸入數據可用。
聲明
以下是java.io.FilterInputStream.read(byte[] b) 方法的聲明:
public int read(byte[] b)
參數
-
b -- The destination buffer.
返回值
該方法返回讀入緩衝區的總字節數,或如果冇有更多的數據讀取返回-1。
異常
-
IOException -- 如果發生I/ O錯誤
例子
下麵的例子顯示java.io.FilterInputStream.read(byte[] b)方法的用法。
package com.yiibai; import java.io.BufferedInputStream; import java.io.FileInputStream; import java.io.FilterInputStream; import java.io.IOException; import java.io.InputStream; public class FilterInputStreamDemo { public static void main(String[] args) throws Exception { InputStream is = null; FilterInputStream fis = null; int i=0; char c; byte[] buffer = new byte[6]; try{ // create input streams is = new FileInputStream("C://test.txt"); fis = new BufferedInputStream(is); // returns number of bytes read to buffer i = fis.read(buffer); // prints System.out.println("Number of bytes read: "+i); // for each byte in buffer for(byte b:buffer) { // converts byte to character c=(char)b; // prints System.out.println("Character read: "+c); } }catch(IOException e){ // if any I/O error occurs e.printStackTrace(); }finally{ // releases any system resources associated with the stream if(is!=null) is.close(); if(fis!=null) fis.close(); } } }
假設我們有一個文本文件c:/ test.txt,它具有以下內容。該文件將被用作輸入到我們的示例程序:
ABCDEF
讓我們來編譯和運行上麵的程序,這將產生以下結果:
Number of bytes read: 6 Character read: A Character read: B Character read: C Character read: D Character read: E Character read: F