Java Reader ready()方法及实例

来源：这里教程网时间：2026-02-17 21:07:45 作者：

Java Reader ready()方法及实例

Java中Reader类的ready()方法是用来检查这个Reader是否准备好被读取。它返回一个布尔值，说明该阅读器是否准备好了。

语法。

public void ready()

参数。该方法不接受任何参数

返回值。这个方法返回一个布尔值，告诉你这个阅读器是否准备好被读取。如果它准备好了，它就返回true。否则，它返回false。

异常。如果在输入-输出时发生一些错误，该方法会抛出 IOException 。

下面的方法说明了ready()方法的工作。

程序 1:

// Java program to demonstrate// Reader ready() method  import java.io.*;import java.util.*;  class GFG {    public static void main(String[] args)    {          try {              String str = "GeeksForGeeks";              // Create a Reader instance            Reader reader                = new StringReader(str);              // Check if the Reader is            // ready to be read using ready()            System.out.println("Is Reader ready "                               + "to be read: "                               + reader.ready());              // Get the character            // to be read from the stream            int ch;              // Read the first 5 characters            // to this reader using read() method            // This will put the str in the stream            // till it is read by the reader            for (int i = 0; i < 5; i++) {                ch = reader.read();                System.out.println("\nInteger value "                                   + "of character read: "                                   + ch);                System.out.println("Actual "                                   + "character read: "                                   + (char)ch);            }              reader.close();        }        catch (Exception e) {            System.out.println(e);        }    }}

输出:

Is Reader ready to be read: trueInteger value of character read: 71Actual character read: GInteger value of character read: 101Actual character read: eInteger value of character read: 101Actual character read: eInteger value of character read: 107Actual character read: kInteger value of character read: 115Actual character read: s

程序2。

// Java program to demonstrate// Reader ready() method  import java.io.*;import java.util.*;  class GFG {    public static void main(String[] args)    {          try {            String str = "GeeksForGeeks";              // Create a Reader instance            Reader reader                = new StringReader(str);              reader.close();              // Check if the Reader is            // ready to be read using ready()            System.out.println("Is Reader ready "                               + "to be read: "                               + reader.ready());              // Get the character            // to be read from the stream            int ch;              // Read the first character            // to this reader using read() method            // This will put the str in the stream            // till it is read by the reader            ch = reader.read();            System.out.println("\nInteger value "                               + "of character read: "                               + ch);            System.out.println("Actual "                               + "character read: "                               + (char)ch);              reader.close();        }        catch (Exception e) {            System.out.println(e);        }    }}

输出: