Java StringReader ready()用法及代碼示例

Java中的StringReader類的ready()方法用於檢查此StringReader是否已準備好被讀取。它返回一個布爾值，該值指示閱讀器是否準備就緒。

用法:

public void ready()

參數：此方法不接受任何參數

返回值：此方法返回一個布爾值，該值指示此StringReader是否準備好被讀取。如果準備就緒，則返回true。否則返回false。

異常：如果輸入輸出時發生某些錯誤，則此方法將引發IOException。

下麵的方法說明了ready()方法的用法方式：

程序1:

// Java program to demonstrate 
// StringReader ready() method 
  
import java.io.*; 
import java.util.*; 
  
class GFG { 
    public static void main(String[] args) 
    { 
  
        try { 
            String str = "GeeksForGeeks"; 
  
            // Create a StringReader instance 
            StringReader reader 
                = new StringReader(str); 
  
            // Check if the StringReader is 
            // ready to be read using ready() 
            System.out.println("Is StringReader 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); 
        } 
    } 
}

輸出：

Is StringReader ready to be read: true

Integer value of character read: 71
Actual character read: G

Integer value of character read: 101
Actual character read: e

Integer value of character read: 101
Actual character read: e

Integer value of character read: 107
Actual character read: k

Integer value of character read: 115
Actual character read: s

程序2:

// Java program to demonstrate 
// StringReader ready() method 
  
import java.io.*; 
import java.util.*; 
  
class GFG { 
    public static void main(String[] args) 
    { 
  
        try { 
            String str = "GeeksForGeeks"; 
  
            // Create a StringReader instance 
            StringReader reader 
                = new StringReader(str); 
  
            reader.close(); 
  
            // Check if the StringReader is 
            // ready to be read using ready() 
            System.out.println("Is StringReader 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); 
        } 
    } 
}

輸出：

java.io.IOException: Stream closed

參考： https://docs.oracle.com/javase/9/docs/api/java/io/StringReader.html#ready-

相關用法

注：本文由純淨天空篩選整理自Code_r大神的英文原創作品 StringReader ready() method in Java with Examples。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。