PushbackReader類ready()方法 (PushbackReader Class ready() method)

• ready() method is available in java.io package.

  ready()方法在java.io包中可用。

• ready() method is used to check whether this stream is ready to be read or not.

  ready()方法用于檢查此流是否已準備好被讀取。

• ready() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.

  ready()方法是一種非靜態方法，只能通過類對象訪問，如果嘗試使用類名稱訪問該方法，則會收到錯誤消息。

• ready() method may throw an exception at the time of checking the state of the stream.

  在檢查流的狀態時， ready()方法可能會引發異常。

  IOException: This exception may throw when getting any input/output error while performing.

  IOException ：在執行過程中遇到任何輸入/輸出錯誤時，可能引發此異常。

Syntax:

句法：

    public boolean ready();

Parameter(s):

參數：

• It does not accept any parameter.

  它不接受任何參數。

Return value:

返回值：

The return type of the method is boolean, it returns true when input data is exists for the next read without blocking otherwise it returns false.

該方法的返回類型為boolean ，如果存在下一次??讀取的輸入數據且沒有阻塞，則返回true，否則返回false。

Example:

例：

// Java program to demonstrate the example 
// of boolean ready() method of
// PushbackReader
import java.io.*;
public class ReadyOfPBR {
public static void main(String[] args) throws Exception {
Reader r_stm = null;
PushbackReader pb_r = null;
try {
// Instantiates Reader and PushbackReader
r_stm = new StringReader("Java World!!!!");
pb_r = new PushbackReader(r_stm);
// By using ready() method is to
// check whether this stream is ready to
// be read or not
boolean status = pb_r.ready();
System.out.println("pb_r.ready(): " + status);
} catch (Exception ex) {
System.out.println(ex.toString());
} finally {
// with the help of this block is to
// free all necessary resources linked
// with the stream
if (r_stm != null) {
r_stm.close();
if (pb_r != null) {
pb_r.close();
}
}
}
}
}

Output

輸出量

pb_r.ready(): true

翻譯自: https://www.includehelp.com/java/pushbackreader-ready-method-with-example.aspx