Java.io.InputStreamReader.ready()方法实例
java.io.InputStreamReader.ready() 方法通知此流是否已准备好被读取。
声明
以下是java.io.InputStreamReader.ready()方法的声明:
public boolean ready()
参数
-
NA
返回值
如果下一读取保证不会阻塞输入,该方法返回true,否则返回false。
异常
-
IOException -- 如果发生I/ O错误
例子
下面的示例演示java.io.InputStreamReader.ready()方法的用法。
package com.yiibai; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStreamReader; public class InputStreamReaderDemo { public static void main(String[] args) throws IOException { FileInputStream fis = null; InputStreamReader isr =null; boolean bool = false; int i; char c; try { // new input stream reader is created fis = new FileInputStream("C:/test.txt"); isr = new InputStreamReader(fis); // reads into the char buffer while((i=isr.read())!=-1) { // converts int to char c=(char)i; // prints the character System.out.println("Character read: "+c); // true if the next read is guaranteed bool = isr.ready(); // prints System.out.println("Ready to read: "+bool); } } catch (Exception e) { // print error e.printStackTrace(); } finally { // closes the stream and releases resources associated if(fis!=null) fis.close(); if(isr!=null) isr.close(); } } }
假设我们有一个文本文件c:/ test.txt,它具有以下内容。该文件将被用作输入到我们的示例程序:
ABCDE
让我们编译和运行上面的程序,这将产生以下结果:
Character read: A Ready to read: true Character read: B Ready to read: true Character read: C Ready to read: true Character read: D Ready to read: true Character read: E Ready to read: false