Java中的PushbackReader类的ready()方法用于检查此PushbackReader是否准备就绪。它返回一个布尔值，该值指示阅读器是否准备就绪。

用法:

public void ready()

参数：此方法不接受任何参数

返回值：此方法返回一个布尔值，该值指示此PushbackReader是否准备好被读取。如果准备就绪，则返回true。否则返回false。

异常：如果输入输出时发生某些错误，则此方法将引发IOException。

下面的方法说明了ready()方法的用法方式：

程序1:

// Java program to demonstrate

// PushbackReader ready() method

import java.io.*;

import java.util.*;

class GFG {

public static void main(String[] args)

{

try {

// Initializing a StringReader

// and PushbackReader

String s = "GeeksForGeeks";

StringReader stringReader

= new StringReader(s);

PushbackReader pushbackReader

= new PushbackReader(stringReader);

// Check if the PushbackReader is

// ready to be read using ready()

System.out.println("Is PushbackReader ready "

+ "to be read: "

+ pushbackReader.ready());

// Close the stream using ready()

pushbackReader.close();

System.out.println("Stream Closed.");

}

catch (Exception e) {

System.out.println(e);

}

}

}

输出：

Is PushbackReader ready to be read: true

Stream Closed.

程序2:

// Java program to demonstrate

// PushbackReader ready() method

import java.io.*;

import java.util.*;

class GFG {

public static void main(String[] args)

{

try {

// Initializing a StringReader

// and PushbackReader

String s = "GFG";

StringReader stringReader

= new StringReader(s);

PushbackReader pushbackReader

= new PushbackReader(stringReader);

// Check if the PushbackReader is

// ready to be read using ready()

System.out.println("Is PushbackReader ready "

+ "to be read: "

+ pushbackReader.ready());

// Close the stream

pushbackReader.close();

System.out.println("Stream Closed.");

}

catch (Exception e) {

System.out.println(e);

}

}

}

输出：

Is PushbackReader ready to be read: true

Stream Closed.