Java PrintStream setError()方法及示例

Java中PrintStream类的setError()方法是用来设置这个PrintStream实例的错误状态。这个方法被用作指示器，表明流中发生了错误。它是受保护的，因此需要通过派生PrintStream类来实现，以使用它。

语法。

protected void setError()

参数。此方法不接受任何参数。

返回值。这个方法不返回任何东西。

下面的方法说明了setError()方法的工作。

程序 1:

// Java program to demonstrate
// PrintStream setError() method
  
import java.io.*;
  
// extending the PrintStream Class
class GFG extends PrintStream {
  
    // Defining the protected constructor
    public GFG(OutputStream out)
    {
        super(System.out);
    }
  
    // Driver Code
    public static void main(String[] args)
    {
  
        // The string to be written in the Stream
        String str = "GeeksForGeeks";
  
        try {
  
            // Create a GFG instance
            GFG stream
                = new GFG(System.out);
  
            // Write the above string to this stream
            // This will put the string in the stream
            // till it is printed on the console
            stream.print(str);
  
            stream.flush();
  
            // Use the protected setError() method
            stream.setError();
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}

输出:

GeeksForGeeks

程序2。

// Java program to demonstrate
// PrintStream setError() method
  
import java.io.*;
  
// extending the PrintStream Class
class GFG extends PrintStream {
  
    // Defining the protected constructor
    public GFG(OutputStream out)
    {
        super(System.out);
    }
  
    // Driver Code
    public static void main(String[] args)
    {
  
        try {
  
            // Create a GFG instance
            GFG stream
                = new GFG(System.out);
  
            // Write the char to this stream
            // This will put the char in the stream
            // till it is printed on the console
            stream.write(65);
  
            stream.flush();
  
            // Use the protected setError() method
            stream.setError();
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}

输出: